nats.docs/_examples/subscribe_json.html

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	<pre id="subscribe_json_go_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/go-nats-examples/blob/master/api-examples/subscribe_json/main.go#L11-43"><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()
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(&#34;updates&#34;, func(s *stock) {
	log.Printf(&#34;Stock: %s - Price: %v&#34;, s.Symbol, s.Price)
	wg.Done()
}); err != nil {
	log.Fatal(err)
}

// Wait for a message to come in
wg.Wait()

</code></pre>
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	<pre id="subscribe_json_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/SubscribeJSON.java#L12-57"><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 StockForJsonSub {
    public String symbol;
    public float price;

    public String toString() {
        return symbol &#43; &#34; is at &#34; &#43; price;
    }
}

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

        try {
            Connection nc = Nats.connect(&#34;nats://demo.nats.io:4222&#34;);

            // 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) -&gt; {
                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(&#34;updates&#34;);

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

            // Close the connection
            nc.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
</code></pre>
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	<pre id="subscribe_json_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#L76-88"><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;,
    json: true
});

nc.subscribe(&#39;updates&#39;, (msg) =&gt; {
    if(msg &amp;&amp; msg.ticker === &#39;TSLA&#39;) {
        t.log(&#39;got message:&#39;, msg);
    }
});

</code></pre>
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	<pre id="subscribe_json_py_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/asyncio-nats-examples/blob/master/subscribe_json.py#L1-23"><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">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=[&#34;nats://127.0.0.1:4222&#34;], loop=loop)

    async def message_handler(msg):
        data = json.loads(msg.data.decode())
        print(data)

    sid = await nc.subscribe(&#34;updates&#34;, cb=message_handler)
    await nc.flush()

    await nc.auto_unsubscribe(sid, 2)
    await nc.publish(&#34;updates&#34;, json.dumps({&#34;symbol&#34;: &#34;GOOG&#34;, &#34;price&#34;: 1200 }).encode())
    await asyncio.sleep(1, loop=loop)
    await nc.close()
</code></pre>
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	<pre id="subscribe_json_ruby_content"><a class="toolbar-icons pull-right" target="_blank" href="https://github.com/nats-io/ruby-nats-examples/blob/master/subscribe_json.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;
require &#39;json&#39;

NATS.start(servers:[&#34;nats://127.0.0.1:4222&#34;]) do |nc|
  nc.subscribe(&#34;updates&#34;) do |msg|
    m = JSON.parse(msg)

    # {&#34;symbol&#34;=&gt;&#34;GOOG&#34;, &#34;price&#34;=&gt;12}
    p m
  end
end
</code></pre>
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	<pre id="subscribe_json_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#L70-80"><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 = await connect({
    url: &#34;nats://demo.nats.io:4222&#34;,
    payload: Payload.JSON
});

nc.subscribe(&#39;updates&#39;, (err, msg) =&gt; {
    t.log(&#39;got message:&#39;, msg.data ? msg.data : &#34;no payload&#34;);
});

</code></pre>
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