nats.docs/docs/developer/examples/servers_added.html

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	<pre id="servers_added_go_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/go-nats-examples/blob/master/api-examples/servers_added/main.go#L10-25"><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-go">// 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(&#34;demo.nats.io&#34;,
	nats.DiscoveredServersHandler(func(nc *nats.Conn) {
		log.Printf(&#34;Known servers: %v\n&#34;, nc.Servers())
		log.Printf(&#34;Discovered servers: %v\n&#34;, nc.DiscoveredServers())
	}))
if err != nil {
	log.Fatal(err)
}
defer nc.Close()

// Do something with the connection

</code></pre>
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	<pre id="servers_added_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/ListenForNewServers.java#L8-37"><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">class ServersAddedListener implements ConnectionListener {
    public void connectionEvent(Connection nc, Events event) {
        if (event == Events.DISCOVERED_SERVERS) {
            for (String server : nc.getServers()) {
                System.out.println(&#34;Known server: &#34;&#43;server);
            }
        }
    }
}

public class ListenForNewServers {
    public static void main(String[] args) {

        try {
            Options options = new Options.Builder().
                                        server(&#34;nats://demo.nats.io:4222&#34;).
                                        connectionListener(new ServersAddedListener()). // Set the listener
                                        build();
            Connection nc = Nats.connect(options);

            // Do something with the connection

            nc.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
</code></pre>
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	<pre id="servers_added_js_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/node-nats-examples/blob/master/src/event_samples.js#L56-61"><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(&#34;nats://demo.nats.io:4222&#34;);
nc.on(&#39;serversDiscovered&#39;, (urls) =&gt; {
    t.log(&#39;serversDiscovered&#39;, urls);
});
</code></pre>
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	<pre id="servers_added_py_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/asyncio-nats-examples/blob/master/notapplicable.txt#L13-15"><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"># Asyncio NATS client does not support discovered servers handler right now
</code></pre>
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	<pre id="servers_added_ruby_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ruby-nats-examples/blob/master/notapplicable.txt#L25-27"><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"># The Ruby NATS client does not support discovered servers handler right now
</code></pre>
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	<pre id="servers_added_ts_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ts-nats-examples/blob/master/src/event_samples.ts#L36-40"><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">nc.on(&#39;serversChanged&#39;, (ce) =&gt; {
    t.log(&#39;servers changed\n&#39;, &#39;added: &#39;,ce.added, &#39;removed:&#39;, ce.removed);
});
</code></pre>
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