nats.docs/_examples/subscribe_async.html

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	<pre id="subscribe_async_go_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/go-nats-examples/blob/master/api-examples/subscribe_async/main.go#L11-34"><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">nc, err := nats.Connect(&#34;demo.nats.io&#34;)
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(&#34;updates&#34;, 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()
</code></pre>
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	<pre id="subscribe_async_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/SubscribeAsync.java#L14-35"><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">Connection nc = Nats.connect(&#34;nats://demo.nats.io:4222&#34;);

// 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) -&gt; {
    String str = new String(msg.getData(), StandardCharsets.UTF_8);
    System.out.println(str);
    latch.countDown();
});

// Subscribe
d.subscribe(&#34;updates&#34;);

// Wait for a message to come in
latch.await(); 

// Close the connection
nc.close();
</code></pre>
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	<pre id="subscribe_async_js_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/node-nats-examples/blob/master/src/subscriber_samples.js#L7-14"><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-javascript">let nc = NATS.connect({
    url: &#34;nats://demo.nats.io:4222&#34;
});
nc.subscribe(&#34;updates&#34;, (msg) =&gt; {
    t.log(msg);
});
</code></pre>
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	<pre id="subscribe_async_py_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/asyncio-nats-examples/blob/master/subscribe_async.py#L6-24"><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()

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

future = asyncio.Future()

async def cb(msg):
  nonlocal future
  future.set_result(msg)

await nc.subscribe(&#34;updates&#34;, cb=cb)
await nc.publish(&#34;updates&#34;, b&#39;All is Well&#39;)
await nc.flush()

# Wait for message to come in
msg = await asyncio.wait_for(future, 1)

</code></pre>
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	<pre id="subscribe_async_ruby_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ruby-nats-examples/blob/master/subscribe_async.rb#L1-13"><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://127.0.0.1:4222&#34;]) do |nc|
  nc.subscribe(&#34;updates&#34;) do |msg|
    puts msg
    nc.close
  end

  nc.publish(&#34;updates&#34;, &#34;All is Well&#34;)
end

</code></pre>
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	<pre id="subscribe_async_ts_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ts-nats-examples/blob/master/src/subscriber_samples.ts#L9-17"><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.subscribe(&#34;updates&#34;, (err, msg) =&gt; {
    if(err) {
        console.log(&#39;error&#39;, err);
    } else {
        t.log(msg.data);
    }
});
</code></pre>
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