Server was incorrectly processing a queue subscription removal
as both a plain sub and queue sub, which may have resulted in
drop of interest even when some queue subs remained.
Resolves#1421
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Say server in cluster A accepts a connection from a server in
cluster B.
The gateway is implicit, in that A does not have a configured
remote gateway to B.
Then the server in B is shutdown, which A detects and initiate
a single reconnect attempt (since it is implicit and if the
reconnect retries is not set).
While this happens, a new server in B is restarted and connects
to A. If that happens before the initial reconnect attempt
failed, A will register that new inbound and do not attempt to
solicit because it has already a remote entry for gateway B.
At this point when the reconnect to old server B fails, then
the remote GW entry is removed, and A will not create an outbound
connection to the new B server.
We fix that by checking if there is a registered inbound when
we get to the point of removing the remote on a failed implicit
reconnect. If there is one, we try the reconnection.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
This contains a rewrite to the services layer for exporting and importing. The code this merges to already had a first significant rewrite that moved from special interest processing to plain subscriptions.
This code changes the prior version's dealing with reverse mapping which was based mostly on thresholds and manual pruning, with some sporadic timer usage. This version uses the jetstream branch's code that understands interest and failed deliveries. So this code is much more tuned to reacting to interest changes. It also removes thresholds and goes only by interest changes or expirations based around a new service export property, response thresholds. This allows a service provider to provide semantics on how long a response should take at a maximum.
This commit also introduces formal support for service export streamed and chunked response types send an empty message to signify EOF.
This commit also includes additions to the service latency tracking such that errors are now sent, not only successful interactions. We have added a Status field and an optional Error fields to ServiceLatency.
We support the following Status codes, these are directly from HTTP.
400 Bad Request (request did not have a reply subject)
408 Request Timeout (when system detects request interest went away, old request style to make dependable)..
503 Service Unavailable (no service responders running)
504 Service Timeout (The new response threshold expired)
Signed-off-by: Derek Collison <derek@nats.io>
Make use of some existing helpers and add checkFor in some places
since accounting updates may not be instantaneous.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
We need to send the unique LDS subject to all leafnodes to properly detect setups like triangles.
This will have the server who completes the loop be the one that detects the error soley based on
its own loop detection subject.
Otehr changes are just to fix tests that were not waiting for the new LDS sub.
Signed-off-by: Derek Collison <derek@nats.io>
This is needed to put those accounts into interest only mode for inbound gateway connections. Also added code
to make sure we were doing proper account tracking and would track the global account as well, which used to
be excluded.
Fixes#977
Signed-off-by: Derek Collison <derek@nats.io>
This is in addition to checking if the own subscription comes back.
The duplicated lds subscription must come from a different client.
Added unit tests.
Also prefixed lds with '$' to mark it as system subject going forward.
This moves the loop detection check past other checks.
These checks should not trigger in cases where a loop is initially detected.
Fixes#1305
Signed-off-by: Matthias Hanel <mh@synadia.com>
For issue #1256, we cleared the possibly saved tlsName on Hanshake failure.
However, this meant that for normal use cases, if a reconnect failed for
any reason we would not be able to reconnect if it is an IP until we get
back to the URL that contained the hostname.
We now clear only if the handshake error is of x509.HostnameError type,
which include errors such as:
```
"x509: Common Name is not a valid hostname: <x>"
"x509: cannot validate certificate for <x> because it doesn't contain any IP SANs"
"x509: certificate is not valid for any names, but wanted to match <x>"
"x509: certificate is valid for <x>, not <y>"
```
Applied the same logic to solicited gateway connections, and fixed the fact
that the tlsConfig should be cloned (since we set the ServerName).
I have also made a change for leafnode connections similar to what we are
doing for gateway connections, which is to use the saved tlsName only if
tlsConfig.ServerName is empty, which may not be the case for users that
embed NATS Server and pass directly tls configuration. In other words,
if the option TLSConfig.ServerName is not empty, always use this value.
Relates to #1256
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
- All writes will now be done by the writeLoop, unless when the
writeLoop has not been started yet (likely in connection init).
- Slow consumers for non CLIENT connections will be reported but
not failed. The idea is that routes, gateway, etc.. connections
should stay connected as much as possible. However if a flush
operation times out and no data at all has been written, the
connection will be closed (regardless of type).
- Slow consumers due to max pending is only for CLIENT connections.
This allows sending of SUBs through routes, etc.. to not have
to be chunked.
- The backpressure to CLIENT connections is increased (up to 1sec)
based on the sub's connection pending bytes level.
- Connection is flushed on close from the writeLoop as to not block
the "fast path".
Some tests have been fixed and adapted since now closeConnection()
is not flushing/closing/removing connection in place.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Updated all tests that use "async" clients.
- start the writeLoop (this is in preparation for changes in the
server that will not do send-in-place for some protocols, such
as PING, etc..)
- Added missing defers in several tests
- fixed an issue in client.go where test was wrong possibly causing
a panic.
- Had to skip a test for now since it would fail without server code
change.
The next step will be ensure that all protocols are sent through
the writeLoop and that the data is properly flushed on close (important
for -ERR for instance).
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
Running test suite on a Windows VM, I notice several failures.
Updated the compute of the RTT to be at least 1ns. I think that
this is just an issue with the VM I am running, but that change
will have no impact for normal situations (since setting the rtt
to the very minimum duration (1ns) instead of 0) and will prevent
some tests from failing.
Because of those same timer granularity issues, I had to add some
delays between some actions in order for time.Sub()/Since() to
actually report something more than 0.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
This is needed for mapped gateway replies. We had used an extra
token when implementing the new prefix, but it was then removed,
but the leafnode subscription on _GR_.*.*.*.> was not updated.
We now subscribe on _GR_.>
There was a test that was passing because we were using inboxes
that caused the pattern to match. Replaced with single token
reply so that it would have caught this bug.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
- New prefix that includes origin server for the request
- Mapping done if request is service import or requestor has
recent subscription
- Subscription considered recent if less than 250ms
- Destination server strip GW prefix before giving to client
and restore when getting a reply on that subject
- Mapping removed aftert 250ms
- Server rejects client publish on "$GNR." (the new prefix)
- Cluster and server hash are now 8 chars long and from base 62
alphabets
- Mapped replies need to be sent to leafnode servers due to race
(cluster B sends RS+ on GW inbound then RMSG on outbound, the
RS+ may be processed later and cluster A may have given message
to LN before RS+ on reply subject. So LN needs to accept the
mapped reply but will strip to give to client and reassemble
before sending it back)
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
This is achieved by subscribing to a unique subject. If the LS+
protocol is coming back for the same subject on the same account,
then this indicates a loop.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
This is the first pass at introducing exported services to the system account for generally debugging of blackbox systems.
The first service reports number of subscribers for a given subject. The payload of the request is the subject, and optional queue group, and can contain wildcards.
Signed-off-by: Derek Collison <derek@nats.io>
- On startup, verify that local account in leafnode (if specified
can be found otherwise fail startup).
- At runtime, print error and continue trying to reconnect.
Will need to decide a better approach.
- When using basic auth (user/password), it was possible for a
solicited Leafnode connection to not use user/password when
trying an URL that was discovered through gossip. The server
now saves the credentials of a configured URL to use with
the discovered ones.
Updated RouteRTT test in case RTT does not seem to be updated
because getting always the same value.
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
When a cluster of servers are having routes to each other, there
is a chance that the list of leafnode URLs maintained on each
server is not complete. This would result in LN servers connecting
to this cluster to not get the full list of possible URLs the
server could reconnect to.
Also fixed a DATA RACE that appeared when running the updated
TestLeafNodeInfoURLs test. Fixed the race and added specific
test that easily demonstrated the race: TestLeafNodeNoRaceGeneratingNonce
Signed-off-by: Ivan Kozlovic <ivan@synadia.com>
When a solicited leafnode comes from multiple servers that themselves are a cluster, cycles were formed.
This change allows solicited leafnodes to behave similar to gateways in that each server of a cluster
is expected to have a solicted leafnode per destination account and cluster.
We no longer forward subscription interest or messages to a cluster from a server that has a solicited leafnode.
Signed-off-by: Derek Collison <derek@nats.io>
