From 230970f41e8b214456f9d9f0b2f016b73218e4cc Mon Sep 17 00:00:00 2001 From: Stephen Asbury Date: Tue, 14 May 2019 17:16:17 -0700 Subject: [PATCH] Started on developer section of the book Added tool to build example html Added book.json to bring in a couple plugins Added building_the_book.md to help with how to build things Updated gitignore with vscode and node modules Checking in initial version of code examples Copy/pasted a couple pages to get started on dev book Updated html template for dev book to support graph vis/copy icon/styles --- .gitignore | 3 + SUMMARY.md | 10 +- _layouts/website/page.html | 395 +++++++++++++++++++ book.json | 6 + building_the_book.md | 11 + developer/README.md | 121 ++++++ developer/connecting.md | 79 ++++ developer/examples/connect_default.html | 115 ++++++ developer/examples/connect_multiple.html | 129 ++++++ developer/examples/connect_name.html | 109 +++++ developer/examples/connect_options.html | 102 +++++ developer/examples/connect_pedantic.html | 112 ++++++ developer/examples/connect_status.html | 144 +++++++ developer/examples/connect_tls.html | 213 ++++++++++ developer/examples/connect_tls_url.html | 191 +++++++++ developer/examples/connect_token.html | 89 +++++ developer/examples/connect_token_url.html | 87 ++++ developer/examples/connect_url.html | 108 +++++ developer/examples/connect_userpass.html | 103 +++++ developer/examples/connect_userpass_url.html | 101 +++++ developer/examples/connect_verbose.html | 112 ++++++ developer/examples/connection_listener.html | 178 +++++++++ developer/examples/control_2k.html | 79 ++++ developer/examples/drain_conn.html | 185 +++++++++ developer/examples/drain_sub.html | 166 ++++++++ developer/examples/error_listener.html | 139 +++++++ developer/examples/flush.html | 132 +++++++ developer/examples/max_payload.html | 115 ++++++ developer/examples/no_echo.html | 105 +++++ developer/examples/ping_20s.html | 111 ++++++ developer/examples/ping_5.html | 118 ++++++ developer/examples/publish_bytes.html | 101 +++++ developer/examples/publish_json.html | 134 +++++++ developer/examples/publish_with_reply.html | 186 +++++++++ developer/examples/reconnect_10s.html | 106 +++++ developer/examples/reconnect_10x.html | 106 +++++ developer/examples/reconnect_5mb.html | 82 ++++ developer/examples/reconnect_event.html | 142 +++++++ developer/examples/reconnect_no_random.html | 118 ++++++ developer/examples/reconnect_none.html | 110 ++++++ developer/examples/request_reply.html | 125 ++++++ developer/examples/servers_added.html | 111 ++++++ developer/examples/slow_listener.html | 154 ++++++++ developer/examples/slow_pending_limits.html | 121 ++++++ developer/examples/subscribe_arrow.html | 195 +++++++++ developer/examples/subscribe_async.html | 140 +++++++ developer/examples/subscribe_json.html | 189 +++++++++ developer/examples/subscribe_queue.html | 143 +++++++ developer/examples/subscribe_star.html | 193 +++++++++ developer/examples/subscribe_sync.html | 100 +++++ developer/examples/subscribe_w_reply.html | 162 ++++++++ developer/examples/unsubscribe.html | 168 ++++++++ developer/examples/unsubscribe_auto.html | 167 ++++++++ developer/examples/wildcard_tester.html | 134 +++++++ docs/index.html | 2 +- docs/nats_server/clients.html | 2 +- docs/nats_server/index.html | 2 +- docs/nats_server/installation.html | 2 +- docs/nats_server/running.html | 2 +- tools/examplecompiler/example_repos.json | 42 ++ tools/examplecompiler/example_template.tmp | 17 + tools/examplecompiler/main.go | 287 ++++++++++++++ 62 files changed, 7202 insertions(+), 9 deletions(-) create mode 100644 _layouts/website/page.html create mode 100644 book.json create mode 100644 building_the_book.md create mode 100644 developer/README.md create mode 100644 developer/connecting.md create mode 100644 developer/examples/connect_default.html create mode 100644 developer/examples/connect_multiple.html create mode 100644 developer/examples/connect_name.html create mode 100644 developer/examples/connect_options.html create mode 100644 developer/examples/connect_pedantic.html create mode 100644 developer/examples/connect_status.html create mode 100644 developer/examples/connect_tls.html create mode 100644 developer/examples/connect_tls_url.html create mode 100644 developer/examples/connect_token.html create mode 100644 developer/examples/connect_token_url.html create mode 100644 developer/examples/connect_url.html create mode 100644 developer/examples/connect_userpass.html create mode 100644 developer/examples/connect_userpass_url.html create mode 100644 developer/examples/connect_verbose.html create mode 100644 developer/examples/connection_listener.html create mode 100644 developer/examples/control_2k.html create mode 100644 developer/examples/drain_conn.html create mode 100644 developer/examples/drain_sub.html create mode 100644 developer/examples/error_listener.html create mode 100644 developer/examples/flush.html create mode 100644 developer/examples/max_payload.html create mode 100644 developer/examples/no_echo.html create mode 100644 developer/examples/ping_20s.html create mode 100644 developer/examples/ping_5.html create mode 100644 developer/examples/publish_bytes.html create mode 100644 developer/examples/publish_json.html create mode 100644 developer/examples/publish_with_reply.html create mode 100644 developer/examples/reconnect_10s.html create mode 100644 developer/examples/reconnect_10x.html create mode 100644 developer/examples/reconnect_5mb.html create mode 100644 developer/examples/reconnect_event.html create mode 100644 developer/examples/reconnect_no_random.html create mode 100644 developer/examples/reconnect_none.html create mode 100644 developer/examples/request_reply.html create mode 100644 developer/examples/servers_added.html create mode 100644 developer/examples/slow_listener.html create mode 100644 developer/examples/slow_pending_limits.html create mode 100644 developer/examples/subscribe_arrow.html create mode 100644 developer/examples/subscribe_async.html create mode 100644 developer/examples/subscribe_json.html create mode 100644 developer/examples/subscribe_queue.html create mode 100644 developer/examples/subscribe_star.html create mode 100644 developer/examples/subscribe_sync.html create mode 100644 developer/examples/subscribe_w_reply.html create mode 100644 developer/examples/unsubscribe.html create mode 100644 developer/examples/unsubscribe_auto.html create mode 100644 developer/examples/wildcard_tester.html create mode 100644 tools/examplecompiler/example_repos.json create mode 100644 tools/examplecompiler/example_template.tmp create mode 100644 tools/examplecompiler/main.go diff --git a/.gitignore b/.gitignore index 09ea21b..c585121 100644 --- a/.gitignore +++ b/.gitignore @@ -1 +1,4 @@ _book/ + +.vscode +node_modules \ No newline at end of file diff --git a/SUMMARY.md b/SUMMARY.md index 2b10714..13a5f6f 100644 --- a/SUMMARY.md +++ b/SUMMARY.md @@ -1,7 +1,9 @@ # Summary * [Introduction](README.md) - * [NATS Server](nats_server/README.md) - * [Installing](nats_server/installation.md) - * [Running](nats_server/running.md) - * [Clients](nats_server/clients.md) +* [NATS Server](nats_server/README.md) + * [Installing](nats_server/installation.md) + * [Running](nats_server/running.md) + * [Clients](nats_server/clients.md) +* [Developing with NATS](developer/README.md) + * [Connecting](developer/connecting.md) diff --git a/_layouts/website/page.html b/_layouts/website/page.html new file mode 100644 index 0000000..3a6ae6b --- /dev/null +++ b/_layouts/website/page.html @@ -0,0 +1,395 @@ +{% extends template.self %} + +{% block head %} +{{ super() }} + +{% endblock %} + +{% block body %} +{{ super() }} + + + + + + + + + + + + +{% endblock %} \ No newline at end of file diff --git a/book.json b/book.json new file mode 100644 index 0000000..d0a212c --- /dev/null +++ b/book.json @@ -0,0 +1,6 @@ +{ + "plugins" : [ "prism", "-highlight", "include-html"], + "pluginsConfig": { + + } +} \ No newline at end of file diff --git a/building_the_book.md b/building_the_book.md new file mode 100644 index 0000000..c93f161 --- /dev/null +++ b/building_the_book.md @@ -0,0 +1,11 @@ +# Building the Book + +The build uses https://github.com/Bandwidth/gitbook-plugin-include-html to include html directly for code examples as well as the prism plugin to handle code highlighting. CSS for code highlighting seems to get mucked up sometimes if you don't use the default them, this is something to work on in the future. + +Icons for dev examples are from https://cdn.materialdesignicons.com/3.6.95/. + +To build the examples + +```bash +% go run tools/examplecompiler/main.go -o developer/examples -r tools/examplecompiler/example_repos.json -t tools/examplecompiler/example_template.tmp +``` \ No newline at end of file diff --git a/developer/README.md b/developer/README.md new file mode 100644 index 0000000..974330a --- /dev/null +++ b/developer/README.md @@ -0,0 +1,121 @@ +# NATS Messaging Concepts + +NATS messaging involves the electronic exchange of data among computer applications and provides a layer between the application and the underlying physical network. Application data is encoded as a message and sent by a publisher. The message is received, decoded, and processed by one or more subscribers. A subscriber can process a NATS message synchronously or asynchronously, depending on the client library used. + +## Asynchronous + +Asynchronous processing uses a callback message handler to process messages. When a message arrives, the registered callback handler receives control to process the message. The client or the consuming application is not blocked from performing other work while it is waiting for a message. Asynchronous processing lets you create multi-threaded dispatching designs. + +## Synchronous + +Synchronous processing requires that application code explicitly call a method to process an incoming message. Typically the message request is a blocking call that suspends processing until a message becomes available and if no message is available, the period for which the message processing call blocks, would be set by the client. Synchronous processing is typically used by a server whose purpose is to wait for and process incoming request messages and to send replies to the requesting application. + +
+graph nats { + graph [splines=ortho, nodesep=1]; + + publisher [shape="record", label="{Application 1 | NATS Publisher}"]; + application [shape="record", label="{Application 3 | }"]; + gnatsd [shape="box", label="", width=4, height=0, penwidth=1]; + subscriber [shape="record", label="{ NATS Subscriber | Application 2}"]; + + publisher:nats -- gnatsd [penwidth=2]; + application:nats -- gnatsd; + gnatsd -- subscriber:nats [penwidth=2, dir="forward"]; +} +
+ +NATS makes it easy for programs to communicate across different environments, languages, and systems because all a client has to do is parse the message. NATS lets programs share common message-handling code, isolate resources and interdependencies, and scale by easily handling an increase in message volume. + +## Publish Subscribe + +NATS implements a publish subscribe message distribution model as a one-to-many communication. A publisher sends a message on a subject and any active subscriber listening on that subject receives the message. Subscribers can also register interest in wildcard subjects. NATS and NATS Streaming combine to offer two qualities of service: + +- **At Most Once Delivery (NATS w/TCP reliability)** - In the basic NATS platform, if a subscriber is not listening on the subject (no subject match), or is not active when the message is sent, the message is not received. NATS is a fire-and-forget messaging system. If you need higher levels of service, you can either use [NATS Streaming](/documentation/streaming/nats-streaming-intro/), or build the additional reliability into your client(s) yourself. + +- **At Least Once Delivery ([NATS Streaming](/documentation/streaming/nats-streaming-intro/))** - Some applications require higher levels of service and more stringent delivery guarantees but at the potential cost of lower message throughput and higher end-to-end delivery latency. These applications rely on the underlying messaging transport to ensure that messages are delivered to subscribers irrespective of network outages or whether or not a subscriber is offline at a particular point in time. + +
+digraph nats_pub_sub { + rankdir=LR + publisher [shape=box, style="rounded", label="Publisher"]; + subject [shape=circle, label="Subject"]; + sub1 [shape=box, style="rounded", label="Subscriber"]; + sub2 [shape=box, style="rounded", label="Subscriber"]; + sub3 [shape=box, style="rounded", label="Subscriber"]; + + publisher -> subject [label="msg1"]; + subject -> sub1 [label="msg1"]; + subject -> sub2 [label="msg1"]; + subject -> sub3 [label="msg1"]; +} +
+ +Try NATS publish subscribe on your own, using a live server by walking through the [pub-sub tutorial](/doc/additional_documentation/nats-pub-sub). + +## Request Reply + +NATS supports two flavors of request reply messaging: point-to-point or one-to-many. Point-to-point involves the fastest or first to respond. In a one-to-many exchange, you set a limit on the number of responses the requestor may receive. + +In a request-response exchange, publish request operation publishes a message with a reply subject expecting a response on that reply subject. You can request to automatically wait for a response inline. + +The request creates an inbox and performs a request call with the inbox reply and returns the first reply received. This is optimized in the case of multiple responses. + +
+digraph nats_request_reply { + rankdir=LR + + subgraph { + publisher [shape=box, style="rounded", label="Publisher"]; + } + + subgraph { + subject [shape=circle, label="Subject"]; + reply [shape=circle, label="Reply"]; + {rank = same subject reply} + } + + subgraph { + sub1 [shape=box, style="rounded", label="Subscriber"]; + sub2 [shape=box, style="rounded", label="Subscriber"]; + sub3 [shape=box, style="rounded", label="Subscriber"]; + } + + publisher -> subject [label="msg1"]; + publisher -> reply [style="invis", weight=2]; + reply -> sub3 [style="invis", weight=2]; + subject -> sub1 [label="msg1", style="dotted"]; + subject -> sub2 [label="msg1", style="dotted"]; + subject -> sub3 [label="msg1"]; + sub3 -> reply; + reply -> publisher; +} +
+ +Try NATS request reply on your own, using a live server by walking through the [request/reply tutorial](/doc/additional_documentation/nats-req-rep). + +## Queue Subscribers & Sharing Work + +NATS provides a load balancing feature called queue subscriptions. Using queue subscribers will load balance message delivery across a group of subscribers which can be used to provide application fault tolerance and scale workload processing. + +To create a queue subscription, subscribers register a queue name. All subscribers with the same queue name form the queue group. As messages on the registered subject are published, one member of the group is chosen randomly to receive the message. Although queue groups have multiple subscribers, each message is consumed by only one. + +Queue subscribers can be asynchronous, in which case the message handler callback function processes the delivered message. Synchronous queue subscribers must build in logic to process the message. Queue subscribers are ideal for auto scaling as you can add or remove them anytime, without any configuration changes or restarting the server or clients. + +
+digraph nats_queues { + rankdir=LR + publisher [shape=box, style="rounded", label="Publisher"]; + subject [shape=circle, label="Queue"]; + sub1 [shape=box, style="rounded", label="Subscriber"]; + sub2 [shape=box, style="rounded", label="Subscriber"]; + sub3 [shape=box, style="rounded", label="Subscriber"]; + + publisher -> subject [label="msgs 1,2,3"]; + subject -> sub1 [label="msg 2"]; + subject -> sub2 [label="msg 1"]; + subject -> sub3 [label="msg 3"]; +} +
+ +Try NATS queue subscriptions on your own, using a live server by walking through the [queueing tutorial](/doc/additional_documentation/nats-queueing). \ No newline at end of file diff --git a/developer/connecting.md b/developer/connecting.md new file mode 100644 index 0000000..3350120 --- /dev/null +++ b/developer/connecting.md @@ -0,0 +1,79 @@ +# Connecting to NATS + +Most client libraries provide several ways to connect to the NATS server, gnatsd. The server itself is identified by a standard URL with the `nats` protocol. Throughout these examples we will rely on a test server, provided by [nats.io](https://nats.io), at `nats://demo.nats.io:4222`, where `4222` is the default port for NATS. + +## Connecting to a Specific Server + +For example, to connect to the demo server with a URL: + +!INCLUDE "examples/connect_url.html" + +## Connecting to the Default Server + +Some libraries also provide a special way to connect to a *default* url, which is general `nats://localhost:4222`: + +!INCLUDE "examples/connect_default.html" + +## Setting a Connect Timeout + +Each library has its own, language preferred way, to pass connection options. For example, to set the maximum time to connect to a server to 10 seconds: + +!INCLUDE "examples/connect_options.html" + +The available options are discussed more below, in other pages, and in the documentation for your client library. + +## Connecting to a Cluster + +When connecting to a cluster, there are a few things to think about. + +* Passing a URL for each cluster member (semi-optional) +* The connection algorithm +* The reconnect algorithm (discussed later) +* Server provided URLs + +When a client connects to the server, the server may provide a list of URLs for additional known servers. This allows a client to connect to one server and still have other servers available during reconnect. However, the initial connection cannot depend on these additional servers. Rather, the additional connection will try to connect to each of the URLs provided in the connect call and will fail if it is unable to connect to any of them. *Note, failure behavior is library dependent, please check the documentation for your client library on information about what happens if the connect fails.* + +!INCLUDE "examples/connect_multiple.html" + +## Reconnecting + +Most, if not all, of the client libraries will reconnect to the server if they are disconnected due to a network problem. The reconnect logic can differ by library, so check your client libraries. In general, the client will try to connect to all of the servers it knows about, either through the URLs provided in `connect` or the URLs provided by its most recent server. The library may have several options to help control reconnect behavior. + +### Disable Reconnect + +For example, you can disable reconnect: + +!INCLUDE "examples/reconnect_none.html" + +### Set the Number of Reconnect Attempts + +Applications can set the maximum reconnect attempts. Generally, this will limit the actual number of attempts total, but check your library documentation. For example, in Java, if the client knows about 3 servers and the maximum reconnects is set to 2, it will not try all of the servers. On the other hand, if the maximum is set to 6 it will try all of the servers twice before considering the reconnect a failure and closing. + +!INCLUDE "examples/reconnect_10x.html" + +### Pausing Between Reconnect Attempts + +It doesn’t make much sense to try to connect to the same server over and over. To prevent this sort of thrashing, and wasted reconnect attempts, libraries provide a wait setting. This setting will pause the reconnect logic if the same server is being tried multiple times. In the previous example, if you have 3 servers and 6 attempts, the Java library would loop over the three servers. If none were connectable, it will then try all three again. However, the Java client doesn’t wait between each attempt, only when trying the same server again, so in that example the library may never wait. If on the other hand, you only provide a single server URL and 6 attempts, the library will wait between each attempt. + +!INCLUDE "examples/reconnect_10s.html" + +### Avoiding the Thundering Herd + +When a server goes down, there is a possible anti-pattern called the *Thundering Herd* where all of the clients try to reconnect immediately creating a denial of service attack. In order to prevent this, most NATS client libraries randomize the servers they attempt to connect to. This setting has no effect if only a single server is used, but in the case of a cluster, randomization, or shuffling, will ensure that no one server bears the brunt of the client reconnect attempts. + +!INCLUDE "examples/reconnect_no_random.html" + +### Listening for Reconnect Events + +Because reconnect is primarily under the covers many libraries provide an event listener you can use to be notified of reconnect events. This event can be especially important for applications sending a lot of messages. + +!INCLUDE "examples/reconnect_event.html" + + +### Buffering Messages During Reconnect Attempts + +There is another setting that comes in to play during reconnection. This setting controls how much memory the client library will hold in the form of outgoing messages while it is disconnected. During a short reconnect, the client will generally allow applications to publish messages but because the server is offline, will be cached in the client. The library will then send those messages on reconnect. When the maximum reconnect buffer is reached, messages will no longer be publishable by the client. + +!INCLUDE "examples/reconnect_5mb.html" + +> *As mentioned throughout this document, each client library may behave slightly differently. Please check the documentation for the library you are using.* \ No newline at end of file diff --git a/developer/examples/connect_default.html b/developer/examples/connect_default.html new file mode 100644 index 0000000..809753e --- /dev/null +++ b/developer/examples/connect_default.html @@ -0,0 +1,115 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect(nats.DefaultURL)
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Connection nc = Nats.connect();
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect();
+nc.on('connect', (c) => {
+    // Do something with the connection
+    doSomething();
+    // When done close it
+    nc.close();
+});
+nc.on('error', (err) => {
+    failed(err);
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect()
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect();
+// Do something with the connection
+
+// When done close it
+nc.close();
+
+
+// alternatively, you can use the Promise pattern
+let nc1: Client;
+connect()
+    .then((c) => {
+        nc1 = c;
+        // Do something with the connection
+        nc1.close();
+    });
+    // add a .catch/.finally
+
+
+ +
diff --git a/developer/examples/connect_multiple.html b/developer/examples/connect_multiple.html new file mode 100644 index 0000000..003003a --- /dev/null +++ b/developer/examples/connect_multiple.html @@ -0,0 +1,129 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
servers := []string{"nats://localhost:1222",
+	"nats://localhost:1223",
+	"nats://localhost:1224",
+}
+
+nc, err := nats.Connect(strings.Join(servers, ","))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://localhost:1222").
+                            server("nats://localhost:1223").
+                            server("nats://localhost:1224").
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    servers: [
+        "nats://demo.nats.io:4222",
+        "nats://localhost:4222"
+    ]}
+);
+
+nc.on('connect', (c) => {
+    // Do something with the connection
+    doSomething();
+    // When done close it
+    nc.close();
+});
+nc.on('error', (err) => {
+    failed(err);
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(servers=[
+   "nats://127.0.0.1:1222",
+   "nats://127.0.0.1:1223",
+   "nats://127.0.0.1:1224"
+   ])
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"]) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+        servers: [
+            "nats://demo.nats.io:4222",
+            "nats://localhost:4222"
+        ]
+});
+// Do something with the connection
+
+// When done close it
+nc.close();
+
+
+ +
diff --git a/developer/examples/connect_name.html b/developer/examples/connect_name.html new file mode 100644 index 0000000..e3584d5 --- /dev/null +++ b/developer/examples/connect_name.html @@ -0,0 +1,109 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set a connection name
+nc, err := nats.Connect("demo.nats.io", nats.Name("my-connection"))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            connectionName("my-connection"). // Set a connection name
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    url: "nats://demo.nats.io:4222",
+    name: "my-connection"
+});
+
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"], name="my-connection")
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://demo.nats.io:4222"], name: "my-connection") do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    name: "my-connection"
+});
+
+nc.close();
+
+
+ +
diff --git a/developer/examples/connect_options.html b/developer/examples/connect_options.html new file mode 100644 index 0000000..a957904 --- /dev/null +++ b/developer/examples/connect_options.html @@ -0,0 +1,102 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect(nats.DefaultURL, nats.Timeout(10*time.Second))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            connectionTimeout(Duration.ofSeconds(10)). // Set timeout
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
// connection timeout is not supported on node-nats
+
+
+ +
+ 
nc = NATS()
+await nc.connect(connect_timeout=2)
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
# There is currently no connect timeout as part of the Ruby NATS client API, but you can use a timer to mimic it.
+require 'nats/client'
+
+timer = EM.add_timer(5) do
+  NATS.connect do |nc|
+    # Do something with the connection
+
+    # Close the connection
+    nc.close
+  end
+end
+EM.cancel_timer(timer)
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    timeout: 1000
+});
+
+
+
+ +
diff --git a/developer/examples/connect_pedantic.html b/developer/examples/connect_pedantic.html new file mode 100644 index 0000000..bed2580 --- /dev/null +++ b/developer/examples/connect_pedantic.html @@ -0,0 +1,112 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
opts := nats.GetDefaultOptions()
+opts.Url = "demo.nats.io"
+// Turn on Pedantic
+opts.Pedantic = true
+nc, err := opts.Connect()
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            pedantic(). // Turn on pedantic
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    url: "nats://demo.nats.io:4222",
+    pedantic: true
+});
+
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"], pedantic=True)
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(pedantic: true) do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    pedantic: true
+});
+
+nc.close();
+
+
+ +
diff --git a/developer/examples/connect_status.html b/developer/examples/connect_status.html new file mode 100644 index 0000000..d578de4 --- /dev/null +++ b/developer/examples/connect_status.html @@ -0,0 +1,144 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+getStatusTxt := func(nc *nats.Conn) string {
+	switch nc.Status() {
+	case nats.CONNECTED:
+		return "Connected"
+	case nats.CLOSED:
+		return "Closed"
+	default:
+		return "Other"
+	}
+}
+log.Printf("The connection is %v\n", getStatusTxt(nc))
+
+nc.Close()
+
+log.Printf("The connection is %v\n", getStatusTxt(nc))
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+System.out.println("The Connection is: " + nc.getStatus());
+
+nc.close();
+
+System.out.println("The Connection is: " + nc.getStatus());
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+
+// on node you *must* register an error listener. If not registered
+// the library emits an 'error' event, the node process will exit.
+nc.on('error', (err) => {
+    t.log('client got an error:', err);
+});
+
+if(nc.closed) {
+    t.log('client is closed');
+} else {
+    t.log('client is not closed');
+}
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   )
+
+# Do something with the connection.
+
+print("The connection is connected?", nc.is_connected)
+
+while True:
+  if nc.is_reconnecting:
+    print("Reconnecting to NATS...")
+    break
+  await asyncio.sleep(1)
+
+await nc.close()
+
+print("The connection is closed?", nc.is_closed)
+
+
+
+ +
+ 
NATS.start(max_reconnect_attempts: 2) do |nc|
+  puts "Connect is connected?: #{nc.connected?}"
+
+  timer = EM.add_periodic_timer(1) do
+    if nc.closing?
+      puts "Connection closed..."
+      EM.cancel_timer(timer)
+      NATS.stop
+    end
+
+    if nc.reconnecting?
+      puts "Reconnecting to NATS..."
+      next
+    end
+  end
+end
+
+
+
+ +
+ 
if(nc.isClosed()) {
+    t.log('the client is closed');
+} else {
+    t.log('the client is running');
+}
+
+
+ +
diff --git a/developer/examples/connect_tls.html b/developer/examples/connect_tls.html new file mode 100644 index 0000000..cb50e42 --- /dev/null +++ b/developer/examples/connect_tls.html @@ -0,0 +1,213 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("localhost",
+	nats.ClientCert("resources/certs/cert.pem", "resources/certs/key.pem"),
+	nats.RootCAs("resources/certs/ca.pem"))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
class SSLUtils {
+    public static String KEYSTORE_PATH = "src/main/resources/keystore.jks";
+    public static String TRUSTSTORE_PATH = "src/main/resources/cacerts";
+    public static String STORE_PASSWORD = "password";
+    public static String KEY_PASSWORD = "password";
+    public static String ALGORITHM = "SunX509";
+
+    public static KeyStore loadKeystore(String path) throws Exception {
+        KeyStore store = KeyStore.getInstance("JKS");
+        BufferedInputStream in = new BufferedInputStream(new FileInputStream(path));
+
+        try {
+            store.load(in, STORE_PASSWORD.toCharArray());
+        } finally {
+            if (in != null) {
+                in.close();
+            }
+        }
+
+        return store;
+    }
+
+    public static KeyManager[] createTestKeyManagers() throws Exception {
+        KeyStore store = loadKeystore(KEYSTORE_PATH);
+        KeyManagerFactory factory = KeyManagerFactory.getInstance(ALGORITHM);
+        factory.init(store, KEY_PASSWORD.toCharArray());
+        return factory.getKeyManagers();
+    }
+
+    public static TrustManager[] createTestTrustManagers() throws Exception {
+        KeyStore store = loadKeystore(TRUSTSTORE_PATH);
+        TrustManagerFactory factory = TrustManagerFactory.getInstance(ALGORITHM);
+        factory.init(store);
+        return factory.getTrustManagers();
+    }
+
+    public static SSLContext createSSLContext() throws Exception {
+        SSLContext ctx = SSLContext.getInstance(Options.DEFAULT_SSL_PROTOCOL);
+        ctx.init(createTestKeyManagers(), createTestTrustManagers(), new SecureRandom());
+        return ctx;
+    }
+}
+
+public class ConnectTLS {
+    public static void main(String[] args) {
+
+        try {
+            SSLContext ctx = SSLUtils.createSSLContext();
+            Options options = new Options.Builder().
+                                server("nats://localhost:4222").
+                                sslContext(ctx). // Set the SSL context
+                                build();
+            Connection nc = Nats.connect(options);
+            
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let caCert = fs.readFileSync(caCertPath);
+let clientCert = fs.readFileSync(clientCertPath);
+let clientKey = fs.readFileSync(clientKeyPath);
+let nc = NATS.connect({
+    url: url,
+    tls: {
+        ca: [caCert],
+        key: [clientKey],
+        cert: [clientCert]
+    }
+});
+
+
+ +
+ 
nc = NATS()
+
+ssl_ctx = ssl.create_default_context(purpose=ssl.Purpose.SERVER_AUTH)
+ssl_ctx.load_verify_locations('ca.pem')
+ssl_ctx.load_cert_chain(certfile='client-cert.pem',
+                        keyfile='client-key.pem')
+await nc.connect(io_loop=loop, tls=ssl_ctx)
+
+await nc.connect(servers=["nats://demo.nats.io:4222"], tls=ssl_ctx)
+
+# Do something with the connection.
+
+
+
+ +
+ 
EM.run do
+
+  options = {
+    :servers => [
+      'nats://localhost:4222',
+    ],
+    :tls => {
+      :private_key_file => './spec/configs/certs/key.pem',
+      :cert_chain_file  => './spec/configs/certs/server.pem'
+    }
+  }
+
+  NATS.connect(options) do |nc|
+    puts "#{Time.now.to_f} - Connected to NATS at #{nc.connected_server}"
+
+    nc.subscribe("hello") do |msg|
+      puts "#{Time.now.to_f} - Received: #{msg}"
+    end
+
+    nc.flush do
+      nc.publish("hello", "world")
+    end
+
+    EM.add_periodic_timer(0.1) do
+      next unless nc.connected?
+      nc.publish("hello", "hello")
+    end
+
+    # Set default callbacks
+    nc.on_error do |e|
+      puts "#{Time.now.to_f } - Error: #{e}"
+    end
+
+    nc.on_disconnect do |reason|
+      puts "#{Time.now.to_f} - Disconnected: #{reason}"
+    end
+
+    nc.on_reconnect do |nc|
+      puts "#{Time.now.to_f} - Reconnected to NATS server at #{nc.connected_server}"
+    end
+
+    nc.on_close do
+      puts "#{Time.now.to_f} - Connection to NATS closed"
+      EM.stop
+    end
+  end
+end
+
+
+ +
+ 
let caCert = readFileSync(caCertPath);
+let clientCert = readFileSync(clientCertPath);
+let clientKey = readFileSync(clientKeyPath);
+let nc = await connect({
+    url: url,
+    tls: {
+        ca: [caCert],
+        key: [clientKey],
+        cert: [clientCert]
+    }
+});
+
+
+ +
diff --git a/developer/examples/connect_tls_url.html b/developer/examples/connect_tls_url.html new file mode 100644 index 0000000..993eee4 --- /dev/null +++ b/developer/examples/connect_tls_url.html @@ -0,0 +1,191 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("localhost",
+	nats.Secure(),
+	nats.RootCAs("resources/certs/ca.pem")) // May need this if server is using self-signed certificate
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
class SSLUtils2 {
+    public static String KEYSTORE_PATH = "src/main/resources/keystore.jks";
+    public static String TRUSTSTORE_PATH = "src/main/resources/cacerts";
+    public static String STORE_PASSWORD = "password";
+    public static String KEY_PASSWORD = "password";
+    public static String ALGORITHM = "SunX509";
+
+    public static KeyStore loadKeystore(String path) throws Exception {
+        KeyStore store = KeyStore.getInstance("JKS");
+        BufferedInputStream in = new BufferedInputStream(new FileInputStream(path));
+
+        try {
+            store.load(in, STORE_PASSWORD.toCharArray());
+        } finally {
+            if (in != null) {
+                in.close();
+            }
+        }
+
+        return store;
+    }
+
+    public static KeyManager[] createTestKeyManagers() throws Exception {
+        KeyStore store = loadKeystore(KEYSTORE_PATH);
+        KeyManagerFactory factory = KeyManagerFactory.getInstance(ALGORITHM);
+        factory.init(store, KEY_PASSWORD.toCharArray());
+        return factory.getKeyManagers();
+    }
+
+    public static TrustManager[] createTestTrustManagers() throws Exception {
+        KeyStore store = loadKeystore(TRUSTSTORE_PATH);
+        TrustManagerFactory factory = TrustManagerFactory.getInstance(ALGORITHM);
+        factory.init(store);
+        return factory.getTrustManagers();
+    }
+
+    public static SSLContext createSSLContext() throws Exception {
+        SSLContext ctx = SSLContext.getInstance(Options.DEFAULT_SSL_PROTOCOL);
+        ctx.init(createTestKeyManagers(), createTestTrustManagers(), new SecureRandom());
+        return ctx;
+    }
+}
+
+public class ConnectTLSURL {
+    public static void main(String[] args) {
+
+        try {
+            SSLContext.setDefault(SSLUtils2.createSSLContext()); // Set the default context
+            Options options = new Options.Builder().
+                                server("tls://localhost:4222"). // Use the TLS protocol
+                                build();
+            Connection nc = Nats.connect(options);
+            
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect({
+    url: "tls://demo.nats.io:4443",
+    tls: true
+});
+
+
+ +
+ 
import asyncio
+import ssl
+import certifi
+from nats.aio.client import Client as NATS
+from nats.aio.errors import ErrTimeout
+
+async def run(loop):
+    nc = NATS()
+
+    # If using Python 3.7 in OS X and getting SSL errors, run first:
+    #
+    # /Applications/Python\ 3.7/Install\ Certificates.command
+    #
+    # Setting the tls as the scheme will use same defaults as `ssl.create_default_context()`
+    #
+    await nc.connect("tls://demo.nats.io:4443", loop=loop)
+
+    async def message_handler(msg):
+        subject = msg.subject
+        reply = msg.reply
+        data = msg.data.decode()
+        print("Received a message on '{subject} {reply}': {data}".format(
+            subject=subject, reply=reply, data=data))
+
+    # Simple publisher and async subscriber via coroutine.
+    sid = await nc.subscribe("foo", cb=message_handler)
+    await nc.flush()
+
+    # Stop receiving after 2 messages.
+    await nc.auto_unsubscribe(sid, 2)
+    await nc.publish("foo", b'Hello')
+    await nc.publish("foo", b'World')
+    await nc.publish("foo", b'!!!!!')
+    await asyncio.sleep(1, loop=loop)
+    await nc.close()
+
+
+ +
+ 
EM.run do
+
+  # In order to use TLS with the Ruby NATS client, use the :tls option
+  # when customizing the connection with an empty block.
+  options = {
+    :servers => [
+      'nats://demo.nats.io:4443',
+    ],
+    :tls => {}
+  }
+
+  NATS.connect(options) do |nc|
+    puts :connected
+  end
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    url: "tls://demo.nats.io:4443"
+});
+
+nc.close();
+
+
+ +
diff --git a/developer/examples/connect_token.html b/developer/examples/connect_token.html new file mode 100644 index 0000000..9b963dc --- /dev/null +++ b/developer/examples/connect_token.html @@ -0,0 +1,89 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set a token
+nc, err := nats.Connect("localhost", nats.Token("mytoken"))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://localhost:4222").
+                            token("mytoken"). // Set a token
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({url: `nats://127.0.0.1:${port}`, token: "mytoken!"});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://mytoken@demo.nats.io:4222"])
+
+# Do something with the connection.
+
+
+
+ +
+ 
NATS.start(token: "deadbeef") do |nc|
+  puts "Connected using token"
+end
+
+
+ +
+ 
let nc = await connect({url: server.nats, token: "mytoken"});
+
+
+ +
diff --git a/developer/examples/connect_token_url.html b/developer/examples/connect_token_url.html new file mode 100644 index 0000000..33081e4 --- /dev/null +++ b/developer/examples/connect_token_url.html @@ -0,0 +1,87 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Token in URL
+nc, err := nats.Connect("mytoken@localhost")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://mytoken@localhost:4222");//Token in URL
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let url = `nats://mytoken!@127.0.0.1:${port}`;
+let nc = NATS.connect({url: url});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://mytoken@demo.nats.io:4222"])
+
+# Do something with the connection.
+
+
+
+ +
+ 
NATS.start("deadbeef@127.0.0.1:4222") do |nc|
+  puts "Connected using token!"
+end
+
+
+ +
+ 
let url = `nats://:mytoken!@127.0.0.1:${port}`;
+let nc = await connect({url: url});
+
+
+ +
diff --git a/developer/examples/connect_url.html b/developer/examples/connect_url.html new file mode 100644 index 0000000..f70c771 --- /dev/null +++ b/developer/examples/connect_url.html @@ -0,0 +1,108 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// If connecting to the default port, the URL can be simplified
+// to just the hostname/IP.
+// That is, the connect below is equivalent to:
+// nats.Connect("nats://demo.nats.io:4222")
+nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+nc.on('connect', (c) => {
+    // Do something with the connection
+    doSomething();
+    // When done close it
+    nc.close();
+});
+nc.on('error', (err) => {
+    failed(err);
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://demo.nats.io:4222"]) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+    let nc = await connect("nats://demo.nats.io:4222");
+    // Do something with the connection
+
+    // Close the connection
+    nc.close();
+
+
+ +
diff --git a/developer/examples/connect_userpass.html b/developer/examples/connect_userpass.html new file mode 100644 index 0000000..e8f0184 --- /dev/null +++ b/developer/examples/connect_userpass.html @@ -0,0 +1,103 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set a user and plain text password
+nc, err := nats.Connect("localhost", nats.UserInfo("myname", "password"))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://localhost:4222").
+                            userInfo("myname","password"). // Set a user and plain text password
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({url: server.nats, user: "myname", pass: "password"});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://myname:password@demo.nats.io:4222"])
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://myname:password@127.0.0.1:4222"], name: "my-connection") do |nc|
+   nc.on_error do |e|
+    puts "Error: #{e}"
+  end
+
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
let nc = await connect({url: server.nats, user: "myname", pass: "password"});
+
+
+ +
diff --git a/developer/examples/connect_userpass_url.html b/developer/examples/connect_userpass_url.html new file mode 100644 index 0000000..3deb7b3 --- /dev/null +++ b/developer/examples/connect_userpass_url.html @@ -0,0 +1,101 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set a user and plain text password
+nc, err := nats.Connect("myname:password@localhost")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://myname:password@localhost:4222");
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let url = `nats://myname:password@127.0.0.1:${port}`;
+let nc = NATS.connect(url);
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://myname:password@demo.nats.io:4222"])
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://myname:password@127.0.0.1:4222"], name: "my-connection") do |nc|
+   nc.on_error do |e|
+    puts "Error: #{e}"
+  end
+
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
let url = `nats://myname:password@127.0.0.1:${port}`;
+let nc = await connect({url: url});
+
+
+ +
diff --git a/developer/examples/connect_verbose.html b/developer/examples/connect_verbose.html new file mode 100644 index 0000000..e793e1b --- /dev/null +++ b/developer/examples/connect_verbose.html @@ -0,0 +1,112 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
opts := nats.GetDefaultOptions()
+opts.Url = "demo.nats.io"
+// Turn on Verbose
+opts.Verbose = true
+nc, err := opts.Connect()
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            verbose(). // Turn on verbose
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    url: "nats://demo.nats.io:4222",
+    verbose: true
+});
+
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"], verbose=True)
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(verbose: true) do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    verbose: true
+});
+
+nc.close();
+
+
+ +
diff --git a/developer/examples/connection_listener.html b/developer/examples/connection_listener.html new file mode 100644 index 0000000..2f5f13b --- /dev/null +++ b/developer/examples/connection_listener.html @@ -0,0 +1,178 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// There is not a single listener for connection events in the NATS Go Client.
+// Instead, you can set individual event handlers using:
+
+DisconnectHandler(cb ConnHandler)
+ReconnectHandler(cb ConnHandler)
+ClosedHandler(cb ConnHandler)
+DiscoveredServersHandler(cb ConnHandler)
+ErrorHandler(cb ErrHandler)
+
+
+ +
+ 
class MyConnectionListener implements ConnectionListener {
+    public void connectionEvent(Connection natsConnection, Events event) {
+        System.out.println("Connection event - "+event);
+    }
+}
+
+public class SetConnectionListener {
+    public static void main(String[] args) {
+
+        try {
+            Options options = new Options.Builder().
+                                        server("nats://demo.nats.io:4222").
+                                        connectionListener(new MyConnectionListener()). // Set the listener
+                                        build();
+            Connection nc = Nats.connect(options);
+
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+
+nc.on('error', (err) => {
+    t.log('error', err);
+});
+
+nc.on('connect', () => {
+    t.log('client connected');
+});
+
+nc.on('disconnect', () => {
+    t.log('client disconnected');
+});
+
+nc.on('reconnecting', () => {
+    t.log('client reconnecting');
+});
+
+nc.on('reconnect', () => {
+    t.log('client reconnected');
+});
+
+nc.on('close', () => {
+    t.log('client closed');
+});
+
+nc.on('permission_error', (err) => {
+    t.log('permission_error', err);
+});
+
+
+ +
+ 
# Asyncio NATS client can be defined a number of event callbacks
+async def disconnected_cb():
+    print("Got disconnected!")
+
+async def reconnected_cb():
+    # See who we are connected to on reconnect.
+    print("Got reconnected to {url}".format(url=nc.connected_url.netloc))
+
+async def error_cb(e):
+    print("There was an error: {}".format(e))
+
+async def closed_cb():
+    print("Connection is closed")
+
+# Setup callbacks to be notified on disconnects and reconnects
+options["disconnected_cb"] = disconnected_cb
+options["reconnected_cb"] = reconnected_cb
+
+# Setup callbacks to be notified when there is an error
+# or connection is closed.
+options["error_cb"] = error_cb
+options["closed_cb"] = closed_cb
+
+await nc.connect(**options)
+
+
+ +
+ 
# There is not a single listener for connection events in the Ruby NATS Client.
+# Instead, you can set individual event handlers using:
+
+NATS.on_disconnect do
+end
+
+NATS.on_reconnect do
+end
+
+NATS.on_close do
+end
+
+NATS.on_error do
+end
+
+
+ +
+ 
// connect will happen once - the first connect
+nc.on('connect', (nc) => {
+    // nc is the connection that connected
+    t.log('client connected');
+});
+
+nc.on('disconnect', (url) => {
+    // nc is the connection that reconnected
+    t.log('disconnected from', url);
+});
+
+nc.on('reconnecting', (url) => {
+    t.log('reconnecting to', url);
+});
+
+nc.on('reconnect', (nc, url) => {
+    // nc is the connection that reconnected
+    t.log('reconnected to', url);
+});
+
+
+ +
diff --git a/developer/examples/control_2k.html b/developer/examples/control_2k.html new file mode 100644 index 0000000..ff2a5ba --- /dev/null +++ b/developer/examples/control_2k.html @@ -0,0 +1,79 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// This does not apply to the NATS Go Client
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            maxControlLine(2 * 1024). // Set the max control line to 2k
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
// set this option before creating a connection
+NATS.MAX_CONTROL_LINE_SIZE = 1024*2;
+let nc = NATS.connect({
+    url: "nats://demo.nats.io:4222"
+});
+
+
+
+ +
+ 
# Asyncio NATS client does not allow custom control lines
+
+
+ +
+ 
# There is no need to customize this in the Ruby NATS client.
+
+
+ +
+ 
// control line size is not configurable on ts-nats
+
+
+ +
diff --git a/developer/examples/drain_conn.html b/developer/examples/drain_conn.html new file mode 100644 index 0000000..dbfd8fa --- /dev/null +++ b/developer/examples/drain_conn.html @@ -0,0 +1,185 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
wg := sync.WaitGroup{}
+wg.Add(1)
+
+errCh := make(chan error, 1)
+
+// To simulate a timeout, you would set the DrainTimeout()
+// to a value less than the time spent in the message callback,
+// so say: nats.DrainTimeout(10*time.Millisecond).
+
+nc, err := nats.Connect("demo.nats.io",
+	nats.DrainTimeout(10*time.Second),
+	nats.ErrorHandler(func(_ *nats.Conn, _ *nats.Subscription, err error) {
+		errCh <- err
+	}),
+	nats.ClosedHandler(func(_ *nats.Conn) {
+		wg.Done()
+	}))
+if err != nil {
+	log.Fatal(err)
+}
+
+// Subscribe, but add some delay while processing.
+if _, err := nc.Subscribe("foo", func(_ *nats.Msg) {
+	time.Sleep(200 * time.Millisecond)
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Publish a message
+if err := nc.Publish("foo", []byte("hello")); err != nil {
+	log.Fatal(err)
+}
+
+// Drain the connection, which will close it when done.
+if err := nc.Drain(); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for the connection to be closed.
+wg.Wait()
+
+// Check if there was an error
+select {
+case e := <-errCh:
+	log.Fatal(e)
+default:
+}
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for a message to arrive
+CountDownLatch latch = new CountDownLatch(1);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("updates");
+
+// Wait for a message to come in
+latch.await();
+
+// Drain the connection, which will close it
+CompletableFuture<Boolean> drained = nc.drain(Duration.ofSeconds(10));
+
+// Wait for the drain to complete
+drained.get();
+
+
+ +
+ 
import asyncio
+from nats.aio.client import Client as NATS
+
+async def example(loop):
+    nc = NATS()
+
+    await nc.connect("nats://127.0.0.1:4222", loop=loop)
+
+    async def handler(msg):
+        print("[Received] ", msg)
+        await nc.publish(msg.reply, b'I can help')
+
+        # Can check whether client is in draining state
+        if nc.is_draining:
+            print("Connection is draining")
+
+    await nc.subscribe("help", "workers", cb=handler)
+    await nc.flush()
+
+    requests = []
+    for i in range(0, 10):
+        request = nc.request("help", b'help!', timeout=1)
+        requests.append(request)
+
+    # Wait for all the responses
+    responses = []
+    responses = await asyncio.gather(*requests)
+
+    # Gracefully close the connection.
+    await nc.drain()
+
+    print("Received {} responses".format(len(responses)))
+
+
+ +
+ 
NATS.start(drain_timeout: 1) do |nc|
+  NATS.subscribe('foo', queue: "workers") do |msg, reply, sub|
+    nc.publish(reply, "ACK:#{msg}")
+  end
+
+  NATS.subscribe('bar', queue: "workers") do |msg, reply, sub|
+    nc.publish(reply, "ACK:#{msg}")
+  end
+
+  NATS.subscribe('quux', queue: "workers") do |msg, reply, sub|
+    nc.publish(reply, "ACK:#{msg}")
+  end
+
+  EM.add_timer(2) do
+    next if NATS.draining?
+
+    # Drain gracefully closes the connection.
+    NATS.drain do
+      puts "Done draining. Connection is closed."
+    end
+  end
+end
+
+
+ +
+ 
let sub = await nc.subscribe('updates', (err, msg) => {
+    t.log('worker got message', msg.data);
+}, {queue: "workers"});
+// [end drain_sub]
+nc.flush();
+
+await nc.drain();
+// client must close when the connection drain resolves
+nc.close();
+
+
+ +
diff --git a/developer/examples/drain_sub.html b/developer/examples/drain_sub.html new file mode 100644 index 0000000..8466970 --- /dev/null +++ b/developer/examples/drain_sub.html @@ -0,0 +1,166 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 

+	nc, err := nats.Connect("demo.nats.io")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer nc.Close()
+
+	done := sync.WaitGroup{}
+	done.Add(1)
+
+	count := 0
+	errCh := make(chan error, 1)
+
+	msgAfterDrain := "not this one"
+
+	// This callback will process each message slowly
+	sub, err := nc.Subscribe("updates", func(m *nats.Msg) {
+		if string(m.Data) == msgAfterDrain {
+			errCh <- fmt.Errorf("Should not have received this message")
+			return
+		}
+		time.Sleep(100 * time.Millisecond)
+		count++
+		if count == 2 {
+			done.Done()
+		}
+	})
+
+	// Send 2 messages
+	for i := 0; i < 2; i++ {
+		nc.Publish("updates", []byte("hello"))
+	}
+
+	// Call Drain on the subscription. It unsubscribes but
+	// wait for all pending messages to be processed.
+	if err := sub.Drain(); err != nil {
+		log.Fatal(err)
+	}
+
+	// Send one more message, this message should not be received
+	nc.Publish("updates", []byte(msgAfterDrain))
+
+	// Wait for the subscription to have processed the 2 messages.
+	done.Wait()
+
+	// Now check that the 3rd message was not received
+	select {
+	case e := <-errCh:
+		log.Fatal(e)
+	case <-time.After(200 * time.Millisecond):
+		// OK!
+	}
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for a message to arrive
+CountDownLatch latch = new CountDownLatch(1);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("updates");
+
+// Wait for a message to come in
+latch.await();
+
+// Messages that have arrived will be processed
+CompletableFuture<Boolean> drained = d.drain(Duration.ofSeconds(10));
+
+// Wait for the drain to complete
+drained.get();
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// Drain subscription is not supported.
+
+
+ +
+ 
import asyncio
+from nats.aio.client import Client as NATS
+
+async def example(loop):
+    nc = NATS()
+
+    await nc.connect("nats://127.0.0.1:4222", loop=loop)
+
+    async def handler(msg):
+        print("[Received] ", msg)
+        await nc.publish(msg.reply, b'I can help')
+
+        # Can check whether client is in draining state
+        if nc.is_draining:
+            print("Connection is draining")
+
+    sid = await nc.subscribe("help", "workers", cb=handler)
+    await nc.flush()
+
+    # Gracefully unsubscribe the subscription
+    await nc.drain(sid)
+
+
+
+ +
+ 
# There is currently no API to drain a single subscription, the whole connection can be drained though via NATS.drain
+
+
+ +
+ 
let sub = await nc.subscribe('updates', (err, msg) => {
+    t.log('worker got message', msg.data);
+}, {queue: "workers"});
+
+
+ +
diff --git a/developer/examples/error_listener.html b/developer/examples/error_listener.html new file mode 100644 index 0000000..35a585a --- /dev/null +++ b/developer/examples/error_listener.html @@ -0,0 +1,139 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set the callback that will be invoked when an asynchronous error occurs.
+nc, err := nats.Connect("demo.nats.io",
+	nats.ErrorHandler(func(nc *nats.Conn, sub *nats.Subscription, err error) {
+		log.Printf("Error: %v", err)
+	}))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
class MyErrorListener implements ErrorListener {
+    public void errorOccurred(Connection conn, String error)
+    {
+        System.out.println("The server notificed the client with: "+error);
+    }
+
+    public void exceptionOccurred(Connection conn, Exception exp) {
+        System.out.println("The connection handled an exception: "+exp.getLocalizedMessage());
+    }
+
+    public void slowConsumerDetected(Connection conn, Consumer consumer) {
+        System.out.println("A slow consumer was detected.");
+    }
+}
+
+public class SetErrorListener {
+    public static void main(String[] args) {
+
+        try {
+            Options options = new Options.Builder().
+                                        server("nats://demo.nats.io:4222").
+                                        errorListener(new MyErrorListener()). // Set the listener
+                                        build();
+            Connection nc = Nats.connect(options);
+
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+
+// on node you *must* register an error listener. If not registered
+// the library emits an 'error' event, the node process will exit.
+nc.on('error', (err) => {
+    t.log('client got an error:', err);
+});
+
+
+ +
+ 
nc = NATS()
+
+async def error_cb(e):
+   print("Error: ", e)
+
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   reconnect_time_wait=10,
+   error_cb=error_cb,
+   )
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://demo.nats.io:4222"]) do |nc|
+   nc.on_error do |e|
+    puts "Error: #{e}"
+  end
+
+  nc.close
+end
+
+
+ +
+ 
// on node you *must* register an error listener. If not registered
+// the library emits an 'error' event, the node process will exit.
+nc.on('error', (err) => {
+    t.log('client got an out of band error:', err);
+});
+
+
+ +
diff --git a/developer/examples/flush.html b/developer/examples/flush.html new file mode 100644 index 0000000..ca9f4e3 --- /dev/null +++ b/developer/examples/flush.html @@ -0,0 +1,132 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+if err := nc.Publish("updates", []byte("All is Well")); err != nil {
+	log.Fatal(err)
+}
+// Sends a PING and wait for a PONG from the server, up to the given timeout.
+// This gives guarantee that the server has processed above message.
+if err := nc.FlushTimeout(time.Second); err != nil {
+	log.Fatal(err)
+}
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+nc.publish("updates", "All is Well".getBytes(StandardCharsets.UTF_8));
+nc.flush(Duration.ofSeconds(1)); // Flush the message queue
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({url: "nats://demo.nats.io:4222"});
+let start = Date.now();
+nc.flush(() => {
+    t.log('round trip completed in', Date.now() - start, 'ms');
+});
+
+nc.publish('foo');
+// function in flush is optional
+nc.flush();
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+await nc.publish("updates", b'All is Well')
+
+# Sends a PING and wait for a PONG from the server, up to the given timeout.
+# This gives guarantee that the server has processed above message.
+await nc.flush(timeout=1)
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.subscribe("updates") do |msg|
+    puts msg
+  end
+
+  nc.publish("updates", "All is Well")
+
+  nc.flush do
+    # Sends a PING and wait for a PONG from the server, up to the given timeout.
+    # This gives guarantee that the server has processed above message at this point.
+  end
+end
+
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222"
+});
+
+// you can use flush to trigger a function in your
+// application once the round-trip to the server finishes
+let start = Date.now();
+nc.flush(() => {
+    t.log('round trip completed in', Date.now() - start, 'ms');
+});
+
+nc.publish('foo');
+
+// another way, simply wait for the promise to resolve
+await nc.flush();
+
+nc.close();
+
+
+ +
diff --git a/developer/examples/max_payload.html b/developer/examples/max_payload.html new file mode 100644 index 0000000..a86e970 --- /dev/null +++ b/developer/examples/max_payload.html @@ -0,0 +1,115 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+mp := nc.MaxPayload()
+log.Printf("Maximum payload is %v bytes", mp)
+
+// Do something with the max payload
+
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+long max = nc.getMaxPayload();
+// Do something with the max payload
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+
+// on node you *must* register an error listener. If not registered
+// the library emits an 'error' event, the node process will exit.
+nc.on('error', (err) => {
+    t.log('client got an error:', err);
+});
+nc.on('connect', () => {
+   t.log(nc.info.max_payload);
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+print("Maximum payload is %d bytes" % nc.max_payload)
+
+# Do something with the max payload.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(max_outstanding_pings: 5) do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  # Do something with the max_payload
+  puts "Maximum Payload is #{nc.server_info[:max_payload]} bytes"
+end
+
+
+ +
+ 
// connect will happen once - the first connect
+nc.on('connect', (nc: Client, url: string, options: ServerInfo) => {
+    // nc is the connection that connected
+    t.log('client connected to', url);
+    t.log('max_payload', options.max_payload);
+});
+
+
+ +
diff --git a/developer/examples/no_echo.html b/developer/examples/no_echo.html new file mode 100644 index 0000000..24853ae --- /dev/null +++ b/developer/examples/no_echo.html @@ -0,0 +1,105 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Turn off echo
+nc, err := nats.Connect("demo.nats.io", nats.NoEcho())
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            noEcho(). // Turn off echo
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
// no_echo is not supported.
+
+
+ +
+ 
ncA = NATS()
+ncB = NATS()
+
+await ncA.connect(no_echo=True)
+await ncB.connect()
+
+async def handler(msg):
+   # Messages sent by `ncA' will not be received.
+   print("[Received] ", msg)
+
+await ncA.subscribe("greetings", cb=handler)
+await ncA.flush()
+await ncA.publish("greetings", b'Hello World!')
+await ncB.publish("greetings", b'Hello World!')
+
+# Do something with the connection
+
+await asyncio.sleep(1)
+await ncA.drain()
+await ncB.drain()
+
+
+
+ +
+ 
NATS.start("nats://demo.nats.io:4222", no_echo: true) do |nc|
+  # ...
+end
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222", noEcho: true});
+
+
+ +
diff --git a/developer/examples/ping_20s.html b/developer/examples/ping_20s.html new file mode 100644 index 0000000..b3bbb0c --- /dev/null +++ b/developer/examples/ping_20s.html @@ -0,0 +1,111 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set Ping Interval to 20 seconds
+nc, err := nats.Connect("demo.nats.io", nats.PingInterval(20*time.Second))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            pingInterval(Duration.ofSeconds(20)). // Set Ping Interval
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    pingInterval: 20*1000, //20s
+    url: "nats://demo.nats.io:4222"
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   # Set Ping Interval to 20 seconds
+   ping_interval=20,
+   )
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(ping_interval: 20) do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  # Do something with the connection
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    pingInterval: 20*2000, //20s
+    url: "nats://demo.nats.io:4222"
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/ping_5.html b/developer/examples/ping_5.html new file mode 100644 index 0000000..45ee0e7 --- /dev/null +++ b/developer/examples/ping_5.html @@ -0,0 +1,118 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
opts := nats.GetDefaultOptions()
+opts.Url = "demo.nats.io"
+// Set maximum number of PINGs out without getting a PONG back
+// before the connection will be disconnected as a stale connection.
+opts.MaxPingsOut = 5
+
+nc, err := opts.Connect()
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            maxPingsOut(5). // Set max pings in flight
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    maxPingOut: 5,
+    url: "nats://demo.nats.io:4222"
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   # Set maximum number of PINGs out without getting a PONG back
+   # before the connection will be disconnected as a stale connection.
+   max_outstanding_pings=5,
+   ping_interval=1,
+   )
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(max_outstanding_pings: 5) do |nc|
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+
+  # Do something with the connection
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    maxPingOut: 5,
+    url: "nats://demo.nats.io:4222"
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/publish_bytes.html b/developer/examples/publish_bytes.html new file mode 100644 index 0000000..595679e --- /dev/null +++ b/developer/examples/publish_bytes.html @@ -0,0 +1,101 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+if err := nc.Publish("updates", []byte("All is Well")); err != nil {
+	log.Fatal(err)
+}
+// Make sure the message goes through before we close
+nc.Flush()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+nc.publish("updates", "All is Well".getBytes(StandardCharsets.UTF_8));
+
+// Make sure the message goes through before we close
+nc.flush(Duration.ZERO);
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({url: "nats://demo.nats.io:4222", preserveBuffers: true});
+let buf = Buffer.allocUnsafe(12);
+buf.fill("All is well");
+nc.publish('updates', buf);
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+await nc.publish("updates", b'All is Well')
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.publish("updates", "All is Well")
+end
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    payload: Payload.BINARY
+});
+
+let buf = Buffer.allocUnsafe(12);
+buf.fill("All is Well");
+nc.publish('updates', buf);
+
+
+ +
diff --git a/developer/examples/publish_json.html b/developer/examples/publish_json.html new file mode 100644 index 0000000..07b58f8 --- /dev/null +++ b/developer/examples/publish_json.html @@ -0,0 +1,134 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+ec, err := nats.NewEncodedConn(nc, nats.JSON_ENCODER)
+if err != nil {
+	nc.Close()
+	log.Fatal(err)
+}
+defer ec.Close()
+
+// Define the object
+type stock struct {
+	Symbol string
+	Price  int
+}
+
+// Publish the message
+if err := ec.Publish("updates", &stock{Symbol: "GOOG", Price: 1200}); err != nil {
+	log.Fatal(err)
+}
+// Make sure the message goes through before we close
+ec.Flush()
+
+
+ +
+ 
class StockForJsonPub {
+    public String symbol;
+    public float price;
+}
+
+public class PublishJSON {
+    public static void main(String[] args) {
+        try {
+            Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+            // Create the data object
+            StockForJsonPub stk = new StockForJsonPub();
+            stk.symbol="GOOG";
+            stk.price=1200;
+
+            // use Gson to encode the object to JSON
+            GsonBuilder builder = new GsonBuilder();
+            Gson gson = builder.create();
+            String json = gson.toJson(stk);
+
+            // Publish the message
+            nc.publish("updates", json.getBytes(StandardCharsets.UTF_8));
+
+            // Make sure the message goes through before we close
+            nc.flush(Duration.ZERO);
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect({url: "nats://demo.nats.io:4222", json: true});
+nc.publish('updates', {ticker: 'GOOG', price: 1200});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+await nc.publish("updates", json.dumps({"symbol": "GOOG", "price": 1200 }).encode())
+
+
+
+ +
+ 
require 'nats/client'
+require 'json'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.publish("updates", {"symbol": "GOOG", "price": 1200}.to_json)
+end
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    payload: Payload.JSON
+});
+
+nc.publish('updates', {ticker: 'GOOG', price: 1200});
+
+
+ +
diff --git a/developer/examples/publish_with_reply.html b/developer/examples/publish_with_reply.html new file mode 100644 index 0000000..ea3defb --- /dev/null +++ b/developer/examples/publish_with_reply.html @@ -0,0 +1,186 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Create a unique subject name
+uniqueReplyTo := nats.NewInbox()
+
+// Listen for a single response
+sub, err := nc.SubscribeSync(uniqueReplyTo)
+if err != nil {
+	log.Fatal(err)
+}
+
+// Send the request
+if err := nc.PublishRequest("time", uniqueReplyTo, nil); err != nil {
+	log.Fatal(err)
+}
+
+// Read the reply
+msg, err := sub.NextMsg(time.Second)
+if err != nil {
+	log.Fatal(err)
+}
+
+// Use the response
+log.Printf("Reply: %s", msg.Data)
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Create a unique subject name
+String uniqueReplyTo = NUID.nextGlobal();
+
+// Listen for a single response
+Subscription sub = nc.subscribe(uniqueReplyTo);
+sub.unsubscribe(1);
+
+// Send the request
+nc.publish("time", uniqueReplyTo, null);
+
+// Read the reply
+Message msg = sub.nextMessage(Duration.ofSeconds(1));
+
+// Use the response
+System.out.println(new String(msg.getData(), StandardCharsets.UTF_8));
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// set up a subscription to process the request
+nc.subscribe('time', (msg, reply) => {
+    if(reply) {
+        nc.publish(reply, new Date().toLocaleTimeString());
+    }
+});
+
+// create a subscription subject that the responding send replies to
+let inbox = NATS.createInbox();
+nc.subscribe(inbox, {max: 1}, (msg) => {
+    t.log('the time is', msg);
+    nc.close();
+});
+
+nc.publish('time', "", inbox);
+
+
+ +
+ 
nc = NATS()
+
+future = asyncio.Future()
+
+async def sub(msg):
+  nonlocal future
+  future.set_result(msg)
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+await nc.subscribe("time", cb=sub)
+
+unique_reply_to = new_inbox()
+await nc.publish_request("time", unique_reply_to, b'')
+
+# Use the response
+msg = await asyncio.wait_for(future, 1)
+print("Reply:", msg)
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("time") do |msg, reply|
+      f.resume msg
+    end
+
+    nc.publish("time", 'example', NATS.create_inbox)
+
+    # Use the response
+    msg = Fiber.yield
+    puts "Reply: #{msg}"
+
+  end.resume
+end
+
+
+
+ +
+ 
// set up a subscription to process the request
+await nc.subscribe('time', (err, msg) => {
+    if (err) {
+        // this example is running inside of a promise
+        reject();
+        return;
+    }
+    if (msg.reply) {
+        nc.publish(msg.reply, new Date().toLocaleTimeString());
+    }
+});
+
+// create a subscription subject that the responding send replies to
+let inbox = createInbox();
+await nc.subscribe(inbox, (err, msg) => {
+    t.log('the time is', msg.data);
+    // this example is running inside of a promise
+    nc.close();
+    resolve();
+}, {max: 1});
+
+nc.publish('time', "", inbox);
+
+
+ +
diff --git a/developer/examples/reconnect_10s.html b/developer/examples/reconnect_10s.html new file mode 100644 index 0000000..0da22be --- /dev/null +++ b/developer/examples/reconnect_10s.html @@ -0,0 +1,106 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set reconnect interval to 10 seconds
+nc, err := nats.Connect("demo.nats.io", nats.ReconnectWait(10*time.Second))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            reconnectWait(Duration.ofSeconds(10)).  // Set Reconnect Wait
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    reconnectTimeWait: 10 * 1000, //10s
+    servers: ["nats://demo.nats.io:4222"]
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   reconnect_time_wait=10,
+   )
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"], reconnect_time_wait: 10) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    reconnectTimeWait: 10*1000, //10s
+    servers: ["nats://demo.nats.io:4222"]
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/reconnect_10x.html b/developer/examples/reconnect_10x.html new file mode 100644 index 0000000..c3836db --- /dev/null +++ b/developer/examples/reconnect_10x.html @@ -0,0 +1,106 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set max reconnects attempts
+nc, err := nats.Connect("demo.nats.io", nats.MaxReconnects(10))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            maxReconnects(10). // Set max reconnect attempts
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    maxReconnectAttempts: 10,
+    servers: ["nats://demo.nats.io:4222"]
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   max_reconnect_attempts=10,
+   )
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"], max_reconnect_attempts: 10) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    maxReconnectAttempts: 10,
+    servers: ["nats://demo.nats.io:4222"]
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/reconnect_5mb.html b/developer/examples/reconnect_5mb.html new file mode 100644 index 0000000..5bd6eee --- /dev/null +++ b/developer/examples/reconnect_5mb.html @@ -0,0 +1,82 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set reconnect buffer size in bytes (5 MB)
+nc, err := nats.Connect("demo.nats.io", nats.ReconnectBufSize(5*1024*1024))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            reconnectBufferSize(5 * 1024 * 1024).  // Set buffer in bytes
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
// Reconnect buffer size is not configurable on node-nats
+
+
+ +
+ 
# Asyncio NATS client currentply does not implement a reconnect buffer
+
+
+ +
+ 
# There is currently no reconnect pending buffer as part of the Ruby NATS client.
+
+
+ +
+ 
// Reconnect buffer size is not configurable on ts-nats
+
+
+ +
diff --git a/developer/examples/reconnect_event.html b/developer/examples/reconnect_event.html new file mode 100644 index 0000000..96b19b0 --- /dev/null +++ b/developer/examples/reconnect_event.html @@ -0,0 +1,142 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Connection event handlers are invoked asynchronously
+// and the state of the connection may have changed when
+// the callback is invoked.
+nc, err := nats.Connect("demo.nats.io",
+	nats.DisconnectHandler(func(nc *nats.Conn) {
+		// handle disconnect event
+	}),
+	nats.ReconnectHandler(func(nc *nats.Conn) {
+		// handle reconnect event
+	}))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            connectionListener((conn, type) -> {
+                                if (type == Events.RECONNECTED) {
+                                    // handle reconnected
+                                } else if (type == Events.DISCONNECTED) {
+                                    // handle disconnected, wait for reconnect
+                                }
+                            }).
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    maxReconnectAttempts: 10,
+    servers: ["nats://demo.nats.io:4222"]
+});
+
+nc.on('reconnect', (c) => {
+    console.log('reconnected');
+});
+
+
+ +
+ 
nc = NATS()
+
+async def disconnected_cb():
+   print("Got disconnected!")
+
+async def reconnected_cb():
+   # See who we are connected to on reconnect.
+   print("Got reconnected to {url}".format(url=nc.connected_url.netloc))
+
+await nc.connect(
+   servers=["nats://demo.nats.io:4222"],
+   reconnect_time_wait=10,
+   reconnected_cb=reconnected_cb,
+   disconnected_cb=disconnected_cb,
+   )
+
+# Do something with the connection.
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"]) do |nc|
+   # Do something with the connection
+   nc.on_reconnect do
+    puts "Got reconnected to #{nc.connected_server}"
+  end
+
+  nc.on_disconnect do |reason|
+    puts "Got disconnected! #{reason}"
+  end
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    maxReconnectAttempts: 10,
+    servers: ["nats://demo.nats.io:4222"]
+});
+// first argument is the connection (same as nc in this case)
+// second argument is the url of the server where the client
+// connected
+nc.on('reconnect', (conn, server) => {
+    console.log('reconnected to', server);
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/reconnect_no_random.html b/developer/examples/reconnect_no_random.html new file mode 100644 index 0000000..6feba88 --- /dev/null +++ b/developer/examples/reconnect_no_random.html @@ -0,0 +1,118 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
servers := []string{"nats://localhost:1222",
+	"nats://localhost:1223",
+	"nats://localhost:1224",
+}
+
+nc, err := nats.Connect(strings.Join(servers, ","), nats.DontRandomize())
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            noRandomize(). // Disable reconnect shuffle
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    noRandomize: false,
+    servers: ["nats://127.0.0.1:4443",
+        "nats://demo.nats.io:4222"
+    ]
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(
+   servers=[
+      "nats://demo.nats.io:1222",
+      "nats://demo.nats.io:1223",
+      "nats://demo.nats.io:1224"
+      ],
+   dont_randomize=True,
+   )
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"], dont_randomize_servers: true) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    noRandomize: false,
+    servers: ["nats://127.0.0.1:4443",
+        "nats://demo.nats.io:4222"
+    ]
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/reconnect_none.html b/developer/examples/reconnect_none.html new file mode 100644 index 0000000..28ae739 --- /dev/null +++ b/developer/examples/reconnect_none.html @@ -0,0 +1,110 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Disable reconnect attempts
+nc, err := nats.Connect("demo.nats.io", nats.NoReconnect())
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
Options options = new Options.Builder().
+                            server("nats://demo.nats.io:4222").
+                            noReconnect(). // Disable reconnect attempts
+                            build();
+Connection nc = Nats.connect(options);
+
+// Do something with the connection
+
+nc.close();
+
+
+ +
+ 
let nc = NATS.connect({
+    reconnect: false,
+    servers: ["nats://demo.nats.io:4222"]
+});
+
+
+ +
+ 
nc = NATS()
+await nc.connect(
+   servers=[
+      "nats://demo.nats.io:1222",
+      "nats://demo.nats.io:1223",
+      "nats://demo.nats.io:1224"
+      ],
+   allow_reconnect=False,
+   )
+
+# Do something with the connection
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers: ["nats://127.0.0.1:1222", "nats://127.0.0.1:1223", "nats://127.0.0.1:1224"], reconnect: false) do |nc|
+   # Do something with the connection
+
+   # Close the connection
+   nc.close
+end
+
+
+ +
+ 
// will throw an exception if connection fails
+let nc = await connect({
+    reconnect: false,
+    servers: ["nats://demo.nats.io:4222"]
+});
+nc.close();
+
+
+ +
diff --git a/developer/examples/request_reply.html b/developer/examples/request_reply.html new file mode 100644 index 0000000..52218e7 --- /dev/null +++ b/developer/examples/request_reply.html @@ -0,0 +1,125 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Send the request
+msg, err := nc.Request("time", nil, time.Second)
+if err != nil {
+	log.Fatal(err)
+}
+
+// Use the response
+log.Printf("Reply: %s", msg.Data)
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Send the request
+Message msg = nc.request("time", null, Duration.ofSeconds(1));
+
+// Use the response
+System.out.println(new String(msg.getData(), StandardCharsets.UTF_8));
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
nc.requestOne('time', (msg) => {
+    t.log('the time is', msg);
+    nc.close();
+});
+
+
+ +
+ 
nc = NATS()
+
+async def sub(msg):
+  await nc.publish(msg.reply, b'response')
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+await nc.subscribe("time", cb=sub)
+
+# Send the request
+try:
+  msg = await nc.request("time", b'', timeout=1)
+  # Use the response
+  print("Reply:", msg)
+except asyncio.TimeoutError:
+  print("Timed out waiting for response")
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.subscribe("time") do |msg, reply|
+    nc.publish(reply, "response")
+  end
+
+  Fiber.new do
+    # Use the response
+    msg = nc.request("time", "")
+    puts "Reply: #{msg}"
+  end.resume
+end
+
+
+
+ +
+ 
let msg = await nc.request('time', 1000);
+t.log('the time is', msg.data);
+nc.close();
+
+
+ +
diff --git a/developer/examples/servers_added.html b/developer/examples/servers_added.html new file mode 100644 index 0000000..5196b7d --- /dev/null +++ b/developer/examples/servers_added.html @@ -0,0 +1,111 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Be notified if a new server joins the cluster.
+// Print all the known servers and the only the ones that were discovered.
+nc, err := nats.Connect("demo.nats.io",
+	nats.DiscoveredServersHandler(func(nc *nats.Conn) {
+		log.Printf("Known servers: %v\n", nc.Servers())
+		log.Printf("Discovered servers: %v\n", nc.DiscoveredServers())
+	}))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
class ServersAddedListener implements ConnectionListener {
+    public void connectionEvent(Connection nc, Events event) {
+        if (event == Events.DISCOVERED_SERVERS) {
+            for (String server : nc.getServers()) {
+                System.out.println("Known server: "+server);
+            }
+        }
+    }
+}
+
+public class ListenForNewServers {
+    public static void main(String[] args) {
+
+        try {
+            Options options = new Options.Builder().
+                                        server("nats://demo.nats.io:4222").
+                                        connectionListener(new ServersAddedListener()). // Set the listener
+                                        build();
+            Connection nc = Nats.connect(options);
+
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect("nats://demo.nats.io:4222");
+nc.on('serversDiscovered', (urls) => {
+    t.log('serversDiscovered', urls);
+});
+
+
+ +
+ 
# Asyncio NATS client does not support discovered servers handler right now
+
+
+ +
+ 
# The Ruby NATS client does not support discovered servers handler right now
+
+
+ +
+ 
nc.on('serversChanged', (ce) => {
+    t.log('servers changed\n', 'added: ',ce.added, 'removed:', ce.removed);
+});
+
+
+ +
diff --git a/developer/examples/slow_listener.html b/developer/examples/slow_listener.html new file mode 100644 index 0000000..e5b8a0b --- /dev/null +++ b/developer/examples/slow_listener.html @@ -0,0 +1,154 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
// Set the callback that will be invoked when an asynchronous error occurs.
+nc, err := nats.Connect("demo.nats.io",
+	nats.ErrorHandler(func(nc *nats.Conn, sub *nats.Subscription, err error) {
+		if err == nats.ErrSlowConsumer {
+			dropped, _ := sub.Dropped()
+			log.Printf("Slow consumer on subject %s dropped %d messages\n",
+				sub.Subject, dropped)
+		}
+	}))
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Do something with the connection
+
+
+
+ +
+ 
class SlowConsumerReporter implements ErrorListener {
+    public void errorOccurred(Connection conn, String error)
+    {
+    }
+
+    public void exceptionOccurred(Connection conn, Exception exp) {
+    }
+
+    // Detect slow consumers
+    public void slowConsumerDetected(Connection conn, Consumer consumer) {
+        // Get the dropped count
+        System.out.println("A slow consumer dropped messages: "+ consumer.getDroppedCount());
+    }
+}
+
+public class SlowConsumerListener {
+    public static void main(String[] args) {
+
+        try {
+            Options options = new Options.Builder().
+                                        server("nats://demo.nats.io:4222").
+                                        errorListener(new SlowConsumerReporter()). // Set the listener
+                                        build();
+            Connection nc = Nats.connect(options);
+
+            // Do something with the connection
+
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
// slow consumer detection is not configurable on node-nats
+
+
+ +
+ 

+   nc = NATS()
+
+   async def error_cb(e):
+     if type(e) is nats.aio.errors.ErrSlowConsumer:
+       print("Slow consumer error, unsubscribing from handling further messages...")
+       await nc.unsubscribe(e.sid)
+
+   await nc.connect(
+      servers=["nats://demo.nats.io:4222"],
+      error_cb=error_cb,
+      )
+
+   msgs = []
+   future = asyncio.Future()
+   async def cb(msg):
+       nonlocal msgs
+       nonlocal future
+       print(msg)
+       msgs.append(msg)
+
+       if len(msgs) == 3:
+         # Head of line blocking on other messages caused
+	 # by single message proccesing taking long...
+         await asyncio.sleep(1)
+
+   await nc.subscribe("updates", cb=cb, pending_msgs_limit=5)
+
+   for i in range(0, 10):
+     await nc.publish("updates", "msg #{}".format(i).encode())
+     await asyncio.sleep(0)
+
+   try:
+     await asyncio.wait_for(future, 1)
+   except asyncio.TimeoutError:
+     pass
+
+   for msg in msgs:
+     print("[Received]", msg)
+
+   await nc.close()
+
+
+
+ +
+ 
# The Ruby NATS client currently does not have option to customize slow consumer limits per sub.
+
+
+ +
+ 
// slow consumer detection is not configurable on ts-nats
+
+
+ +
diff --git a/developer/examples/slow_pending_limits.html b/developer/examples/slow_pending_limits.html new file mode 100644 index 0000000..8027557 --- /dev/null +++ b/developer/examples/slow_pending_limits.html @@ -0,0 +1,121 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Subscribe
+sub1, err := nc.Subscribe("updates", func(m *nats.Msg) {})
+if err != nil {
+	log.Fatal(err)
+}
+
+// Set limits of 1000 messages or 5MB, whichever comes first
+sub1.SetPendingLimits(1000, 5*1024*1024)
+
+// Subscribe
+sub2, err := nc.Subscribe("updates", func(m *nats.Msg) {})
+if err != nil {
+	log.Fatal(err)
+}
+
+// Set no limits for this subscription
+sub2.SetPendingLimits(-1, -1)
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+Dispatcher d = nc.createDispatcher((msg) -> {
+    // do something
+});
+
+d.subscribe("updates");
+
+d.setPendingLimits(1_000, 5 * 1024 * 1024); // Set limits on a dispatcher
+
+// Subscribe
+Subscription sub = nc.subscribe("updates");
+
+sub.setPendingLimits(1_000, 5 * 1024 * 1024); // Set limits on a subscription
+
+// Do something
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// slow pending limits are not configurable on node-nats
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+future = asyncio.Future()
+
+async def cb(msg):
+  nonlocal future
+  future.set_result(msg)
+
+# Set limits of 1000 messages or 5MB
+await nc.subscribe("updates", cb=cb, pending_bytes_limit=5*1024*1024, pending_msgs_limit=1000)
+
+
+
+ +
+ 
# The Ruby NATS client currently does not have option to customize slow consumer limits per sub.
+
+
+ +
+ 
// slow pending limits are not configurable on ts-nats
+
+
+ +
diff --git a/developer/examples/subscribe_arrow.html b/developer/examples/subscribe_arrow.html new file mode 100644 index 0000000..c84f090 --- /dev/null +++ b/developer/examples/subscribe_arrow.html @@ -0,0 +1,195 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Use a WaitGroup to wait for 4 messages to arrive
+wg := sync.WaitGroup{}
+wg.Add(4)
+
+// Subscribe
+if _, err := nc.Subscribe("time.>", func(m *nats.Msg) {
+	log.Printf("%s: %s", m.Subject, m.Data)
+	wg.Done()
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for the 4 messages to come in
+wg.Wait()
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for 4 messages to arrive
+CountDownLatch latch = new CountDownLatch(4);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String subject = msg.getSubject();
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(subject + ": " + str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("time.>");
+
+// Wait for messages to come in
+latch.await();
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
nc.subscribe('time.>', (msg, reply, subject) => {
+    // converting timezones correctly in node requires a library
+    // this doesn't take into account *many* things.
+    let time = "";
+    switch (subject) {
+        case 'time.us.east':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/New_York"});
+            break;
+        case 'time.us.central':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Chicago"});
+            break;
+        case 'time.us.mountain':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Denver"});
+            break;
+        case 'time.us.west':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Los_Angeles"});
+            break;
+        default:
+            time = "I don't know what you are talking about Willis";
+    }
+    t.log(subject, time);
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+# Use queue to wait for 4 messages to arrive
+queue = asyncio.Queue()
+async def cb(msg):
+  await queue.put(msg)
+
+await nc.subscribe("time.>", cb=cb)
+
+# Send 2 messages and wait for them to come in
+await nc.publish("time.A.east", b'A')
+await nc.publish("time.B.east", b'B')
+await nc.publish("time.C.west", b'C')
+await nc.publish("time.D.west", b'D')
+
+for i in range(0, 4):
+  msg = await queue.get()
+  print("Msg:", msg)
+
+await nc.close()
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("time.>") do |msg, reply|
+      f.resume Time.now.to_f
+    end
+
+    nc.publish("time.A.east", "A")
+    nc.publish("time.B.east", "B")
+    nc.publish("time.C.west", "C")
+    nc.publish("time.D.west", "D")
+
+    # Use the response
+    4.times do 
+      msg = Fiber.yield
+      puts "Msg: #{msg}"
+    end
+  end.resume
+end
+
+
+
+ +
+ 
await nc.subscribe('time.>', (err, msg) => {
+    // converting timezones correctly in node requires a library
+    // this doesn't take into account *many* things.
+    let time = "";
+    switch (msg.subject) {
+        case 'time.us.east':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/New_York"});
+            break;
+        case 'time.us.central':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Chicago"});
+            break;
+        case 'time.us.mountain':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Denver"});
+            break;
+        case 'time.us.west':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Los_Angeles"});
+            break;
+        default:
+            time = "I don't know what you are talking about Willis";
+    }
+    t.log(msg.subject, time);
+});
+
+
+ +
diff --git a/developer/examples/subscribe_async.html b/developer/examples/subscribe_async.html new file mode 100644 index 0000000..bf97365 --- /dev/null +++ b/developer/examples/subscribe_async.html @@ -0,0 +1,140 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Use a WaitGroup to wait for a message to arrive
+wg := sync.WaitGroup{}
+wg.Add(1)
+
+// Subscribe
+if _, err := nc.Subscribe("updates", func(m *nats.Msg) {
+	wg.Done()
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for a message to come in
+wg.Wait()
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for a message to arrive
+CountDownLatch latch = new CountDownLatch(1);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("updates");
+
+// Wait for a message to come in
+latch.await(); 
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
nc.subscribe("updates", (msg) => {
+    t.log(msg);
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+future = asyncio.Future()
+
+async def cb(msg):
+  nonlocal future
+  future.set_result(msg)
+
+await nc.subscribe("updates", cb=cb)
+await nc.publish("updates", b'All is Well')
+await nc.flush()
+
+# Wait for message to come in
+msg = await asyncio.wait_for(future, 1)
+
+
+
+ +
+ 
require 'nats/client'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.subscribe("updates") do |msg|
+    puts msg
+    nc.close
+  end
+
+  nc.publish("updates", "All is Well")
+end
+
+
+
+ +
+ 
nc.subscribe("updates", (err, msg) => {
+    if(err) {
+        console.log('error', err);
+    } else {
+        t.log(msg.data);
+    }
+});
+
+
+ +
diff --git a/developer/examples/subscribe_json.html b/developer/examples/subscribe_json.html new file mode 100644 index 0000000..3b379ca --- /dev/null +++ b/developer/examples/subscribe_json.html @@ -0,0 +1,189 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+ec, err := nats.NewEncodedConn(nc, nats.JSON_ENCODER)
+if err != nil {
+	log.Fatal(err)
+}
+defer ec.Close()
+
+// Define the object
+type stock struct {
+	Symbol string
+	Price  int
+}
+
+wg := sync.WaitGroup{}
+wg.Add(1)
+
+// Subscribe
+if _, err := ec.Subscribe("updates", func(s *stock) {
+	log.Printf("Stock: %s - Price: %v", s.Symbol, s.Price)
+	wg.Done()
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for a message to come in
+wg.Wait()
+
+// Close the connection
+ec.Close()
+
+
+ +
+ 
class StockForJsonSub {
+    public String symbol;
+    public float price;
+
+    public String toString() {
+        return symbol + " is at " + price;
+    }
+}
+
+public class SubscribeJSON {
+    public static void main(String[] args) {
+
+        try {
+            Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+            // Use a latch to wait for 10 messages to arrive
+            CountDownLatch latch = new CountDownLatch(10);
+
+            // Create a dispatcher and inline message handler
+            Dispatcher d = nc.createDispatcher((msg) -> {
+                Gson gson = new Gson();
+
+                String json = new String(msg.getData(), StandardCharsets.UTF_8);
+                StockForJsonSub stk = gson.fromJson(json, StockForJsonSub.class);
+                
+                // Use the object
+                System.out.println(stk);
+
+                latch.countDown();
+            });
+
+            // Subscribe
+            d.subscribe("updates");
+
+            // Wait for a message to come in
+            latch.await(); 
+
+            // Close the connection
+            nc.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+
+ +
+ 
let nc = NATS.connect({
+    url: "nats://demo.nats.io:4222",
+    json: true
+});
+
+nc.subscribe('updates', (msg) => {
+    if(msg && msg.ticker === 'TSLA') {
+        t.log('got message:', msg);
+    }
+});
+
+
+
+ +
+ 
import asyncio
+import json
+from nats.aio.client import Client as NATS
+from nats.aio.errors import ErrTimeout
+
+async def run(loop):
+    nc = NATS()
+
+    await nc.connect(servers=["nats://127.0.0.1:4222"], loop=loop)
+
+    async def message_handler(msg):
+        data = json.loads(msg.data.decode())
+        print(data)
+
+    sid = await nc.subscribe("updates", cb=message_handler)
+    await nc.flush()
+
+    await nc.auto_unsubscribe(sid, 2)
+    await nc.publish("updates", json.dumps({"symbol": "GOOG", "price": 1200 }).encode())
+    await asyncio.sleep(1, loop=loop)
+    await nc.close()
+
+
+ +
+ 
require 'nats/client'
+require 'json'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  nc.subscribe("updates") do |msg|
+    m = JSON.parse(msg)
+
+    # {"symbol"=>"GOOG", "price"=>12}
+    p m
+  end
+end
+
+
+ +
+ 
let nc = await connect({
+    url: "nats://demo.nats.io:4222",
+    payload: Payload.JSON
+});
+
+nc.subscribe('updates', (err, msg) => {
+    t.log('got message:', msg.data ? msg.data : "no payload");
+});
+
+
+
+ +
diff --git a/developer/examples/subscribe_queue.html b/developer/examples/subscribe_queue.html new file mode 100644 index 0000000..2f52a62 --- /dev/null +++ b/developer/examples/subscribe_queue.html @@ -0,0 +1,143 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Use a WaitGroup to wait for 10 messages to arrive
+wg := sync.WaitGroup{}
+wg.Add(10)
+
+// Create a queue subscription on "updates" with queue name "workers"
+if _, err := nc.QueueSubscribe("updates", "worker", func(m *nats.Msg) {
+	wg.Done()
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for messages to come in
+wg.Wait()
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for 10 messages to arrive
+CountDownLatch latch = new CountDownLatch(10);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("updates", "workers");
+
+// Wait for a message to come in
+latch.await(); 
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
nc.subscribe('updates', {queue: "workers"}, (msg) => {
+    t.log('worker got message', msg);
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+future = asyncio.Future()
+
+async def cb(msg):
+  nonlocal future
+  future.set_result(msg)
+
+await nc.subscribe("updates", queue="workers", cb=cb)
+await nc.publish("updates", b'All is Well')
+
+msg = await asyncio.wait_for(future, 1)
+print("Msg", msg)
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("updates", queue: "worker") do |msg, reply|
+      f.resume Time.now
+    end
+
+    nc.publish("updates", "A")
+
+    # Use the response
+    msg = Fiber.yield
+    puts "Msg: #{msg}"
+  end.resume
+end
+
+
+
+ +
+ 
await nc.subscribe('updates', (err, msg) => {
+    t.log('worker got message', msg.data);
+}, {queue: "workers"});
+
+
+ +
diff --git a/developer/examples/subscribe_star.html b/developer/examples/subscribe_star.html new file mode 100644 index 0000000..90c757c --- /dev/null +++ b/developer/examples/subscribe_star.html @@ -0,0 +1,193 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Use a WaitGroup to wait for 2 messages to arrive
+wg := sync.WaitGroup{}
+wg.Add(2)
+
+// Subscribe
+if _, err := nc.Subscribe("time.*.east", func(m *nats.Msg) {
+	log.Printf("%s: %s", m.Subject, m.Data)
+	wg.Done()
+}); err != nil {
+	log.Fatal(err)
+}
+
+// Wait for the 2 messages to come in
+wg.Wait()
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Use a latch to wait for 2 messages to arrive
+CountDownLatch latch = new CountDownLatch(2);
+
+// Create a dispatcher and inline message handler
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String subject = msg.getSubject();
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(subject + ": " + str);
+    latch.countDown();
+});
+
+// Subscribe
+d.subscribe("time.*.east");
+
+// Wait for messages to come in
+latch.await();
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
nc.subscribe('time.us.*', (msg, reply, subject) => {
+    // converting timezones correctly in node requires a library
+    // this doesn't take into account *many* things.
+    let time = "";
+    switch (subject) {
+        case 'time.us.east':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/New_York"});
+            break;
+        case 'time.us.central':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Chicago"});
+            break;
+        case 'time.us.mountain':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Denver"});
+            break;
+        case 'time.us.west':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Los_Angeles"});
+            break;
+        default:
+            time = "I don't know what you are talking about Willis";
+    }
+    t.log(subject, time);
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+# Use queue to wait for 2 messages to arrive
+queue = asyncio.Queue()
+async def cb(msg):
+  await queue.put_nowait(msg)
+
+await nc.subscribe("time.*.east", cb=cb)
+
+# Send 2 messages and wait for them to come in
+await nc.publish("time.A.east", b'A')
+await nc.publish("time.B.east", b'B')
+
+msg_A = await queue.get()
+msg_B = await queue.get()
+
+print("Msg A:", msg_A)
+print("Msg B:", msg_B)
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("time.*.east") do |msg, reply|
+      f.resume Time.now
+    end
+
+    nc.publish("time.A.east", "A")
+    nc.publish("time.B.east", "B")
+
+    # Use the response
+    msg_A = Fiber.yield
+    puts "Msg A: #{msg_A}"
+
+    msg_B = Fiber.yield
+    puts "Msg B: #{msg_B}"
+
+  end.resume
+end
+
+
+
+ +
+ 
await nc.subscribe('time.us.*', (err, msg) => {
+    // converting timezones correctly in node requires a library
+    // this doesn't take into account *many* things.
+    let time = "";
+    switch (msg.subject) {
+        case 'time.us.east':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/New_York"});
+            break;
+        case 'time.us.central':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Chicago"});
+            break;
+        case 'time.us.mountain':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Denver"});
+            break;
+        case 'time.us.west':
+            time = new Date().toLocaleTimeString("en-us", {timeZone: "America/Los_Angeles"});
+            break;
+        default:
+            time = "I don't know what you are talking about Willis";
+    }
+    console.log(msg.subject, time);
+});
+
+
+ +
diff --git a/developer/examples/subscribe_sync.html b/developer/examples/subscribe_sync.html new file mode 100644 index 0000000..f5ec811 --- /dev/null +++ b/developer/examples/subscribe_sync.html @@ -0,0 +1,100 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Subscribe
+sub, err := nc.SubscribeSync("updates")
+if err != nil {
+	log.Fatal(err)
+}
+
+// Wait for a message
+msg, err := sub.NextMsg(10 * time.Second)
+if err != nil {
+	log.Fatal(err)
+}
+
+// Use the response
+log.Printf("Reply: %s", msg.Data)
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Subscribe
+Subscription sub = nc.subscribe("updates");
+
+// Read a message
+Message msg = sub.nextMessage(Duration.ZERO);
+
+String str = new String(msg.getData(), StandardCharsets.UTF_8);
+System.out.println(str);
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// node-nats subscriptions are always async.
+
+
+ +
+ 
# Asyncio NATS client currently does not have a sync subscribe API
+
+
+ +
+ 
# The Ruby NATS client subscriptions are all async.
+
+
+ +
+ 
// ts-nats subscriptions are always async.
+
+
+ +
diff --git a/developer/examples/subscribe_w_reply.html b/developer/examples/subscribe_w_reply.html new file mode 100644 index 0000000..9541927 --- /dev/null +++ b/developer/examples/subscribe_w_reply.html @@ -0,0 +1,162 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Subscribe
+sub, err := nc.SubscribeSync("time")
+if err != nil {
+	log.Fatal(err)
+}
+
+// Read a message
+msg, err := sub.NextMsg(10 * time.Second)
+if err != nil {
+	log.Fatal(err)
+}
+
+// Get the time
+timeAsBytes := []byte(time.Now().String())
+
+// Send the time
+nc.Publish(msg.Reply, timeAsBytes)
+
+// Flush and close the connection
+nc.Flush()
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+
+// Subscribe
+Subscription sub = nc.subscribe("time");
+
+// Read a message
+Message msg = sub.nextMessage(Duration.ZERO);
+
+// Get the time
+Calendar cal = Calendar.getInstance();
+SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
+byte[] timeAsBytes = sdf.format(cal.getTime()).getBytes(StandardCharsets.UTF_8);
+
+// Send the time
+nc.publish(msg.getReplyTo(), timeAsBytes);
+
+// Flush and close the connection
+nc.flush(Duration.ZERO);
+nc.close();
+
+
+ +
+ 
// set up a subscription to process a request
+nc.subscribe('time', (msg, reply) => {
+    if (msg.reply) {
+        nc.publish(msg.reply, new Date().toLocaleTimeString());
+    }
+});
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+future = asyncio.Future()
+
+async def cb(msg):
+  nonlocal future
+  future.set_result(msg)
+
+await nc.subscribe("time", cb=cb)
+
+await nc.publish_request("time", new_inbox(), b'What is the time?')
+await nc.flush()
+
+# Read the message
+msg = await asyncio.wait_for(future, 1)
+
+# Send the time
+time_as_bytes = "{}".format(datetime.now()).encode()
+await nc.publish(msg.reply, time_as_bytes)
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("time") do |msg, reply|
+      f.resume Time.now
+    end
+
+    nc.publish("time", 'What is the time?', NATS.create_inbox)
+
+    # Use the response
+    msg = Fiber.yield
+    puts "Reply: #{msg}"
+
+  end.resume
+end
+
+
+
+ +
+ 
// set up a subscription to process a request
+await nc.subscribe('time', (err, msg) => {
+    if (msg.reply) {
+        nc.publish(msg.reply, new Date().toLocaleTimeString());
+    } else {
+        t.log('got a request for the time, but no reply subject was set.');
+    }
+});
+
+
+ +
diff --git a/developer/examples/unsubscribe.html b/developer/examples/unsubscribe.html new file mode 100644 index 0000000..db04ad3 --- /dev/null +++ b/developer/examples/unsubscribe.html @@ -0,0 +1,168 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Sync Subscription
+sub, err := nc.SubscribeSync("updates")
+if err != nil {
+	log.Fatal(err)
+}
+if err := sub.Unsubscribe(); err != nil {
+	log.Fatal(err)
+}
+
+// Async Subscription
+sub, err = nc.Subscribe("updates", func(_ *nats.Msg) {})
+if err != nil {
+	log.Fatal(err)
+}
+if err := sub.Unsubscribe(); err != nil {
+	log.Fatal(err)
+}
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+});
+
+// Sync Subscription
+Subscription sub = nc.subscribe("updates");
+sub.unsubscribe();
+
+// Async Subscription
+d.subscribe("updates");
+d.unsubscribe("updates");
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// set up a subscription to process a request
+let sub = nc.subscribe(NATS.createInbox(), (msg, reply) => {
+    if (msg.reply) {
+        nc.publish(reply, new Date().toLocaleTimeString());
+    }
+});
+
+// without arguments the subscription will cancel when the server receives it
+// you can also specify how many messages are expected by the subscription
+nc.unsubscribe(sub);
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+future = asyncio.Future()
+
+async def cb(msg):
+  nonlocal future
+  future.set_result(msg)
+
+sid = await nc.subscribe("updates", cb=cb)
+await nc.publish("updates", b'All is Well')
+
+# Remove interest in subject
+await nc.unsubscribe(sid)
+
+# Won't be received...
+await nc.publish("updates", b'...')
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    sid = nc.subscribe("time") do |msg, reply|
+      f.resume Time.now
+    end
+
+    nc.publish("time", 'What is the time?', NATS.create_inbox)
+
+    # Use the response
+    msg = Fiber.yield
+    puts "Reply: #{msg}"
+
+    nc.unsubscribe(sid)
+
+    # Won't be received
+    nc.publish("time", 'What is the time?', NATS.create_inbox)
+
+  end.resume
+end
+
+
+
+ +
+ 
// set up a subscription to process a request
+let sub = await nc.subscribe(createInbox(), (err, msg) => {
+    if (msg.reply) {
+        nc.publish(msg.reply, new Date().toLocaleTimeString());
+    } else {
+        t.log('got a request for the time, but no reply subject was set.');
+    }
+});
+
+// without arguments the subscription will cancel when the server receives it
+// you can also specify how many messages are expected by the subscription
+sub.unsubscribe();
+
+
+ +
diff --git a/developer/examples/unsubscribe_auto.html b/developer/examples/unsubscribe_auto.html new file mode 100644 index 0000000..a6590db --- /dev/null +++ b/developer/examples/unsubscribe_auto.html @@ -0,0 +1,167 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+// Sync Subscription
+sub, err := nc.SubscribeSync("updates")
+if err != nil {
+	log.Fatal(err)
+}
+if err := sub.AutoUnsubscribe(1); err != nil {
+	log.Fatal(err)
+}
+
+// Async Subscription
+sub, err = nc.Subscribe("updates", func(_ *nats.Msg) {})
+if err != nil {
+	log.Fatal(err)
+}
+if err := sub.AutoUnsubscribe(1); err != nil {
+	log.Fatal(err)
+}
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+Dispatcher d = nc.createDispatcher((msg) -> {
+    String str = new String(msg.getData(), StandardCharsets.UTF_8);
+    System.out.println(str);
+});
+
+// Sync Subscription
+Subscription sub = nc.subscribe("updates");
+sub.unsubscribe(1);
+
+// Async Subscription
+d.subscribe("updates");
+d.unsubscribe("updates", 1);
+
+// Close the connection
+nc.close();
+
+
+ +
+ 
// `max` specifies the number of messages that the server will forward.
+// The server will auto-cancel.
+let opts = {max: 10};
+let sub = nc.subscribe(NATS.createInbox(), opts, (msg) => {
+    t.log(msg);
+});
+
+// another way after 10 messages
+let sub2 = nc.subscribe(NATS.createInbox(), (err, msg) => {
+    t.log(msg.data);
+});
+// if the subscription already received 10 messages, the handler
+// won't get any more messages
+nc.unsubscribe(sub2, 10);
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+async def cb(msg):
+  print(msg)
+
+sid = await nc.subscribe("updates", cb=cb)
+await nc.auto_unsubscribe(sid, 1)
+await nc.publish("updates", b'All is Well')
+
+# Won't be received...
+await nc.publish("updates", b'...')
+
+
+
+ +
+ 
require 'nats/client'
+require 'fiber'
+
+NATS.start(servers:["nats://127.0.0.1:4222"]) do |nc|
+  Fiber.new do
+    f = Fiber.current
+
+    nc.subscribe("time", max: 1) do |msg, reply|
+      f.resume Time.now
+    end
+
+    nc.publish("time", 'What is the time?', NATS.create_inbox)
+
+    # Use the response
+    msg = Fiber.yield
+    puts "Reply: #{msg}"
+
+    # Won't be received
+    nc.publish("time", 'What is the time?', NATS.create_inbox)
+
+  end.resume
+end
+
+
+
+ +
+ 
// `max` specifies the number of messages that the server will forward.
+// The server will auto-cancel.
+let opts = {max: 10};
+let sub = await nc.subscribe(createInbox(), (err, msg) => {
+    t.log(msg.data);
+}, opts);
+
+// another way after 10 messages
+let sub2 = await nc.subscribe(createInbox(), (err, msg) => {
+    t.log(msg.data);
+});
+// if the subscription already received 10 messages, the handler
+// won't get any more messages
+sub2.unsubscribe(10);
+
+
+ +
diff --git a/developer/examples/wildcard_tester.html b/developer/examples/wildcard_tester.html new file mode 100644 index 0000000..f6fa80e --- /dev/null +++ b/developer/examples/wildcard_tester.html @@ -0,0 +1,134 @@ + +
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
+ 
nc, err := nats.Connect("demo.nats.io")
+if err != nil {
+	log.Fatal(err)
+}
+defer nc.Close()
+
+zoneID, err := time.LoadLocation("America/New_York")
+if err != nil {
+	log.Fatal(err)
+}
+now := time.Now()
+zoneDateTime := now.In(zoneID)
+formatted := zoneDateTime.String()
+
+nc.Publish("time.us.east", []byte(formatted))
+nc.Publish("time.us.east.atlanta", []byte(formatted))
+
+zoneID, err = time.LoadLocation("Europe/Warsaw")
+if err != nil {
+	log.Fatal(err)
+}
+zoneDateTime = now.In(zoneID)
+formatted = zoneDateTime.String()
+
+nc.Publish("time.eu.east", []byte(formatted))
+nc.Publish("time.eu.east.warsaw", []byte(formatted))
+
+// Close the connection
+nc.Close()
+
+
+ +
+ 
Connection nc = Nats.connect("nats://demo.nats.io:4222");
+ZoneId zoneId = ZoneId.of("America/New_York");
+ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(Instant.now(), zoneId);
+String formatted = zonedDateTime.format(DateTimeFormatter.ISO_ZONED_DATE_TIME);
+
+nc.publish("time.us.east", formatted.getBytes(StandardCharsets.UTF_8));
+nc.publish("time.us.east.atlanta", formatted.getBytes(StandardCharsets.UTF_8));
+
+zoneId = ZoneId.of("Europe/Warsaw");
+zonedDateTime = ZonedDateTime.ofInstant(Instant.now(), zoneId);
+formatted = zonedDateTime.format(DateTimeFormatter.ISO_ZONED_DATE_TIME);
+nc.publish("time.eu.east", formatted.getBytes(StandardCharsets.UTF_8));
+nc.publish("time.eu.east.warsaw", formatted.getBytes(StandardCharsets.UTF_8));
+
+nc.flush(Duration.ZERO);
+nc.close();
+
+
+ +
+ 
nc.publish('time.us.east');
+nc.publish('time.us.central');
+nc.publish('time.us.mountain');
+nc.publish('time.us.west');
+
+
+ +
+ 
nc = NATS()
+
+await nc.connect(servers=["nats://demo.nats.io:4222"])
+
+await nc.publish("time.us.east", b'...')
+await nc.publish("time.us.east.atlanta", b'...')
+
+await nc.publish("time.eu.east", b'...')
+await nc.publish("time.eu.east.warsaw", b'...')
+
+await nc.close()
+
+
+
+ +
+ 
NATS.start do |nc|
+   nc.publish("time.us.east", '...')
+   nc.publish("time.us.east.atlanta", '...')
+
+   nc.publish("time.eu.east", '...')
+   nc.publish("time.eu.east.warsaw", '...')
+
+   nc.drain
+end
+
+
+ +
+ 
nc.publish('time.us.east');
+nc.publish('time.us.central');
+nc.publish('time.us.mountain');
+nc.publish('time.us.west');
+
+
+ +
diff --git a/docs/index.html b/docs/index.html index 092c249..19057cd 100644 --- a/docs/index.html +++ b/docs/index.html @@ -249,7 +249,7 @@ diff --git a/docs/nats_server/clients.html b/docs/nats_server/clients.html index 41817ab..1d4c674 100644 --- a/docs/nats_server/clients.html +++ b/docs/nats_server/clients.html @@ -266,7 +266,7 @@ Published [hello] : 'world' diff --git a/docs/nats_server/index.html b/docs/nats_server/index.html index 8b3a564..4b47c80 100644 --- a/docs/nats_server/index.html +++ b/docs/nats_server/index.html @@ -259,7 +259,7 @@ diff --git a/docs/nats_server/installation.html b/docs/nats_server/installation.html index 00a5de8..bf6311b 100644 --- a/docs/nats_server/installation.html +++ b/docs/nats_server/installation.html @@ -288,7 +288,7 @@ Archive: nats-server.zip diff --git a/docs/nats_server/running.html b/docs/nats_server/running.html index 849caa2..c56bac8 100644 --- a/docs/nats_server/running.html +++ b/docs/nats_server/running.html @@ -276,7 +276,7 @@ By default, security is not enabled.

diff --git a/tools/examplecompiler/example_repos.json b/tools/examplecompiler/example_repos.json new file mode 100644 index 0000000..97bd6e7 --- /dev/null +++ b/tools/examplecompiler/example_repos.json @@ -0,0 +1,42 @@ +[{ + "LanguageName": "java", + "FormalName": "Java", + "RepoURL": "https://github.com/nats-io/java-nats-examples.git", + "Extensions": [".java", ".txt"], + "SyntaxClass": "language-java" +}, +{ + "LanguageName": "go", + "FormalName": "Go", + "RepoURL": "https://github.com/nats-io/go-nats-examples.git", + "Extensions": [".go", ".txt"], + "SyntaxClass": "language-go" +}, +{ + "LanguageName": "ts", + "FormalName": "TypeScript", + "RepoURL": "https://github.com/nats-io/ts-nats-examples.git", + "Extensions": [".ts", ".txt"], + "SyntaxClass": "language-javascript" +}, +{ + "LanguageName": "js", + "FormalName": "JavaScript", + "RepoURL": "https://github.com/nats-io/node-nats-examples.git", + "Extensions": [".js", ".txt"], + "SyntaxClass": "language-javascript" +}, +{ + "LanguageName": "py", + "FormalName": "Python", + "RepoURL": "https://github.com/nats-io/asyncio-nats-examples.git", + "Extensions": [".py", ".txt"], + "SyntaxClass": "language-python" +}, +{ + "LanguageName": "ruby", + "FormalName": "Ruby", + "RepoURL": "https://github.com/nats-io/ruby-nats-examples.git", + "Extensions": [".rb", ".txt"], + "SyntaxClass": "language-ruby" +}] \ No newline at end of file diff --git a/tools/examplecompiler/example_template.tmp b/tools/examplecompiler/example_template.tmp new file mode 100644 index 0000000..ce08560 --- /dev/null +++ b/tools/examplecompiler/example_template.tmp @@ -0,0 +1,17 @@ +{{$n := .Name}} +
+ {{range .Languages}} + {{if .First}} + + {{else}} + + {{end}} + + {{end}} + + {{range .Languages}} +
+ 
{{.Content}}
+
+ {{end}} +
diff --git a/tools/examplecompiler/main.go b/tools/examplecompiler/main.go new file mode 100644 index 0000000..a11982c --- /dev/null +++ b/tools/examplecompiler/main.go @@ -0,0 +1,287 @@ +package main + +import ( + "encoding/json" + "bufio" + "bytes" + "flag" + "fmt" + "html/template" + "io/ioutil" + "log" + "os" + "os/exec" + "path/filepath" + "regexp" + "sort" + "strings" + "unicode" +) + +type exampleRepo struct { + LanguageName string + FormalName string + RepoURL string + Extensions []string + SyntaxClass string +} + +type languageExample struct { + Language string + FormalName string + Content string + RepoURL string + SyntaxClass string + First bool +} + +type languageList []languageExample + +func (s languageList) Len() int { + return len(s) +} +func (s languageList) Swap(i, j int) { + s[i], s[j] = s[j], s[i] +} +func (s languageList) Less(i, j int) bool { + return s[i].Language < s[j].Language +} + +type example struct { + Name string + Languages languageList +} + +func searchRepo(repoDirectory string, repo exampleRepo, examples map[string]*example) error { + + extensions := make(map[string]string) + for _, ext := range repo.Extensions { + extensions[ext] = ext + } + + fmt.Printf("Searching for examples in: %q\n", repoDirectory) + + err := filepath.Walk(repoDirectory, func(path string, info os.FileInfo, err error) error { + if err != nil { + fmt.Printf("prevent panic by handling failure accessing a path %q: %v\n", repoDirectory, err) + return err + } + + ext := filepath.Ext(path) + + if _, ok := extensions[ext]; ok { + fmt.Printf("\tReading: %q\n", info.Name()) + file, err := os.Open(path) + if err != nil { + log.Fatal(err) + } + defer file.Close() + + var buffer bytes.Buffer + exampleName := "" + beginExample, err := regexp.Compile(`\[begin ([^\s\[\]]+)\]`) + + if err != nil { + log.Fatal(err) + } + + endExample, err := regexp.Compile(`\[end ([^\s\[\]]+)\]`) + + if err != nil { + log.Fatal(err) + } + + scanner := bufio.NewScanner(file) + lineNumber := 1 + beginLineNumber := lineNumber + relativePath, err := filepath.Rel(repoDirectory, path) + var indentRegex *regexp.Regexp + + if err != nil { + log.Fatal(err) + } + + for scanner.Scan() { + currentLine := scanner.Text() + + if exampleName == "" { + matches := beginExample.FindStringSubmatch(currentLine) + + if len(matches) == 2 { + exampleName = matches[1] + beginLineNumber = lineNumber + endExample, err = regexp.Compile(`\[end ` + exampleName + `\]`) + if err != nil { + log.Fatal(err) + } + } + } else if endExample.FindStringSubmatch(currentLine) != nil { + fmt.Printf("\t\tFound %q example\n", exampleName) + + if _, ok := examples[exampleName]; !ok { + examples[exampleName] = &example{ + Name: exampleName, + Languages: []languageExample{}, + } + } + + simpleRepoURL := strings.Replace(repo.RepoURL, ".git", "", -1) + gitHubURL := fmt.Sprintf("%s/blob/master/%s#L%d-%d", simpleRepoURL, relativePath, beginLineNumber, lineNumber) + example := examples[exampleName] + langExample := languageExample{ + Language: repo.LanguageName, + FormalName: repo.FormalName, + SyntaxClass: repo.SyntaxClass, + Content: buffer.String(), + RepoURL: gitHubURL, + } + + example.Languages = append(example.Languages, langExample) + + // fmt.Printf("\t\tRepo url: %s\n", langExample.RepoURL) + + exampleName = "" // Look for another example in this file + buffer.Reset() + } else { + // Calculate indent from first line + // Blindly chop following lines (this could be smarter) + if buffer.Len() == 0 { + before := len(currentLine) + currentLine = strings.TrimLeftFunc(currentLine, func(r rune) bool { + return unicode.IsSpace(r) + }) + after := len(currentLine) + indent := before - after + + if indent > 0 { + indentRegexString := fmt.Sprintf("^\\s{0,%d}", indent) + indentRegex, err = regexp.Compile(indentRegexString) + } + } else { + if indentRegex != nil { + currentLine = string(indentRegex.ReplaceAllString(currentLine, "")) + } + } + buffer.WriteString(currentLine) + buffer.WriteString("\n") + } + + lineNumber++ + } + + if err := scanner.Err(); err != nil { + log.Fatal(err) + } + } + + return nil + }) + + if err != nil { + fmt.Printf("error walking the path %q: %v\n", repoDirectory, err) + } + + return err +} + +func formatExamples(examples map[string]*example, exampleTemplate *template.Template, outputFolder string) { + fmt.Printf("Formatting examples\n") + + for _, example := range examples { + if len(example.Languages) == 0 { + fmt.Printf("\tSkipping empty example %q\n", example.Name) + return + } + + sort.Sort(languageList(example.Languages)) + example.Languages[0].First = true + + var buffer bytes.Buffer + err := exampleTemplate.Execute(&buffer, example) + if err != nil { + log.Fatal(err) + } + + htmlPath := filepath.Join(outputFolder, fmt.Sprintf("%s.html", example.Name)) + err = ioutil.WriteFile(htmlPath, buffer.Bytes(), 0666) + if err != nil { + log.Fatal(err) + } + fmt.Printf("\tFormatted %q to %q\n", example.Name, htmlPath) + } +} + +func usage() { + log.Fatalf("Usage: examplecompiler -o -t