nats.docs/docs/developer/examples/reconnect_event.html

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	<pre id="reconnect_event_go_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/go-nats-examples/blob/master/api-examples/reconnect_event/main.go#L10-28"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-go">// Connection event handlers are invoked asynchronously
// and the state of the connection may have changed when
// the callback is invoked.
nc, err := nats.Connect(&#34;demo.nats.io&#34;,
	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

</code></pre>
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	<pre id="reconnect_event_java_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/java-nats-examples/blob/master/src/main/java/io/nats/examples/ReconnectEvents.java#L12-28"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-java">Options options = new Options.Builder().
                            server(&#34;nats://demo.nats.io:4222&#34;).
                            connectionListener((conn, type) -&gt; {
                                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();
</code></pre>
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	<pre id="reconnect_event_js_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/node-nats-examples/blob/master/src/reconnect_samples.js#L74-83"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-javascript">let nc = NATS.connect({
    maxReconnectAttempts: 10,
    servers: [&#34;nats://demo.nats.io:4222&#34;]
});

nc.on(&#39;reconnect&#39;, (c) =&gt; {
    console.log(&#39;reconnected&#39;);
});
</code></pre>
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	<pre id="reconnect_event_py_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/asyncio-nats-examples/blob/master/reconnect_event.py#L6-25"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-python">nc = NATS()

async def disconnected_cb():
   print(&#34;Got disconnected!&#34;)

async def reconnected_cb():
   # See who we are connected to on reconnect.
   print(&#34;Got reconnected to {url}&#34;.format(url=nc.connected_url.netloc))

await nc.connect(
   servers=[&#34;nats://demo.nats.io:4222&#34;],
   reconnect_time_wait=10,
   reconnected_cb=reconnected_cb,
   disconnected_cb=disconnected_cb,
   )

# Do something with the connection.

</code></pre>
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	<pre id="reconnect_event_ruby_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ruby-nats-examples/blob/master/reconnect_event.rb#L1-14"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-ruby">require &#39;nats/client&#39;

NATS.start(servers: [&#34;nats://127.0.0.1:1222&#34;, &#34;nats://127.0.0.1:1223&#34;, &#34;nats://127.0.0.1:1224&#34;]) do |nc|
   # Do something with the connection
   nc.on_reconnect do
    puts &#34;Got reconnected to #{nc.connected_server}&#34;
  end

  nc.on_disconnect do |reason|
    puts &#34;Got disconnected! #{reason}&#34;
  end
end
</code></pre>
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	<pre id="reconnect_event_ts_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ts-nats-examples/blob/master/src/reconnect_samples.ts#L57-70"><i class="mdi mdi-github-circle" title="View on GitHub"></i></a><a class="toolbar-icons pull-right"><i class="mdi mdi-content-copy js-copy" title="Copy to Clipboard"></i></a><span class="copy-msg pull-right"></span><code class="language-javascript">// will throw an exception if connection fails
let nc = await connect({
    maxReconnectAttempts: 10,
    servers: [&#34;nats://demo.nats.io:4222&#34;]
});
// 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(&#39;reconnect&#39;, (conn, server) =&gt; {
    console.log(&#39;reconnected to&#39;, server);
});
nc.close();
</code></pre>
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