<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Pulsar adaptor for Apache Storm · Apache Pulsar</title><meta name="viewport" content="width=device-width, initial-scale=1.0"/><meta name="generator" content="Docusaurus"/><meta name="description" content="Pulsar Storm is an adaptor for integrating with [Apache Storm](http://storm.apache.org/) topologies. It provides core Storm implementations for sending and receiving data."/><meta name="docsearch:version" content="2.3.1"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Pulsar adaptor for Apache Storm · Apache Pulsar"/><meta property="og:type" content="website"/><meta property="og:url" content="https://pulsar.apache.org/"/><meta property="og:description" content="Pulsar Storm is an adaptor for integrating with [Apache Storm](http://storm.apache.org/) topologies. It provides core Storm implementations for sending and receiving data."/><meta name="twitter:card" content="summary"/><meta name="twitter:image" content="https://pulsar.apache.org/img/pulsar.svg"/><link rel="shortcut icon" href="/img/pulsar.ico"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/atom-one-dark.min.css"/><link rel="alternate" type="application/atom+xml" href="https://pulsar.apache.org/blog/atom.xml" title="Apache Pulsar Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://pulsar.apache.org/blog/feed.xml" title="Apache Pulsar Blog RSS Feed"/><link rel="stylesheet" href="/css/code-blocks-buttons.css"/><script type="text/javascript" src="https://buttons.github.io/buttons.js"></script><script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.0/clipboard.min.js"></script><script type="text/javascript" src="/js/custom.js"></script><script src="/js/scrollSpy.js"></script><link rel="stylesheet" href="/css/main.css"/><script src="/js/codetabs.js"></script></head><body class="sideNavVisible separateOnPageNav"><div class="fixedHeaderContainer"><div class="headerWrapper wrapper"><header><a href="/en"><img class="logo" src="/img/pulsar.svg" alt="Apache Pulsar"/></a><a href="/en/versions"><h3>2.3.1</h3></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li class="siteNavGroupActive"><a href="/docs/en/2.3.1/getting-started-standalone" target="_self">Docs</a></li><li class=""><a href="/en/download" target="_self">Download</a></li><li class="siteNavGroupActive"><a href="/docs/en/2.3.1/client-libraries" target="_self">Clients</a></li><li class=""><a href="#restapis" target="_self">REST APIs</a></li><li class=""><a href="#cli" target="_self">Cli</a></li><li class=""><a href="/blog/" target="_self">Blog</a></li><li class=""><a href="#community" target="_self">Community</a></li><li class=""><a href="#apache" target="_self">Apache</a></li><li class=""><a href="https://pulsar-next.staged.apache.org/" target="_self">New Website (Beta)</a></li><span><li><a id="languages-menu" href="#"><img class="languages-icon" src="/img/language.svg" alt="Languages icon"/>English</a><div id="languages-dropdown" class="hide"><ul id="languages-dropdown-items"><li><a href="/docs/ja/2.3.1/adaptors-storm">日本語</a></li><li><a href="/docs/fr/2.3.1/adaptors-storm">Français</a></li><li><a href="/docs/ko/2.3.1/adaptors-storm">한국어</a></li><li><a href="/docs/zh-CN/2.3.1/adaptors-storm">中文</a></li><li><a href="/docs/zh-TW/2.3.1/adaptors-storm">繁體中文</a></li><li><a href="https://crowdin.com/project/apache-pulsar" target="_blank" rel="noreferrer noopener">Help Translate</a></li></ul></div></li><script>
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<p>An application can inject data into a Storm topology via a generic Pulsar spout, as well as consume data from a Storm topology via a generic Pulsar bolt.</p>
<h2><a class="anchor" aria-hidden="true" id="using-the-pulsar-storm-adaptor"></a><a href="#using-the-pulsar-storm-adaptor" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Using the Pulsar Storm Adaptor</h2>
<p>Include dependency for Pulsar Storm Adaptor:</p>
<pre><code class="hljs css language-xml"><span class="hljs-tag">&lt;<span class="hljs-name">dependency</span>&gt;</span>
  <span class="hljs-tag">&lt;<span class="hljs-name">groupId</span>&gt;</span>org.apache.pulsar<span class="hljs-tag">&lt;/<span class="hljs-name">groupId</span>&gt;</span>
  <span class="hljs-tag">&lt;<span class="hljs-name">artifactId</span>&gt;</span>pulsar-storm<span class="hljs-tag">&lt;/<span class="hljs-name">artifactId</span>&gt;</span>
  <span class="hljs-tag">&lt;<span class="hljs-name">version</span>&gt;</span>${pulsar.version}<span class="hljs-tag">&lt;/<span class="hljs-name">version</span>&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">dependency</span>&gt;</span>
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="pulsar-spout"></a><a href="#pulsar-spout" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Pulsar Spout</h2>
<p>The Pulsar Spout allows for the data published on a topic to be consumed by a Storm topology. It emits a Storm tuple based on the message received and the <code>MessageToValuesMapper</code> provided by the client.</p>
<p>The tuples that fail to be processed by the downstream bolts will be re-injected by the spout with an exponential backoff, within a configurable timeout (the default is 60 seconds) or a configurable number of retries, whichever comes first, after which it is acknowledged by the consumer. Here's an example construction of a spout:</p>
<pre><code class="hljs css language-java">MessageToValuesMapper messageToValuesMapper = <span class="hljs-keyword">new</span> MessageToValuesMapper() {

    <span class="hljs-meta">@Override</span>
    <span class="hljs-function"><span class="hljs-keyword">public</span> Values <span class="hljs-title">toValues</span><span class="hljs-params">(Message msg)</span> </span>{
        <span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> Values(<span class="hljs-keyword">new</span> String(msg.getData()));
    }

    <span class="hljs-meta">@Override</span>
    <span class="hljs-function"><span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">declareOutputFields</span><span class="hljs-params">(OutputFieldsDeclarer declarer)</span> </span>{
        <span class="hljs-comment">// declare the output fields</span>
        declarer.declare(<span class="hljs-keyword">new</span> Fields(<span class="hljs-string">"string"</span>));
    }
};

<span class="hljs-comment">// Configure a Pulsar Spout</span>
PulsarSpoutConfiguration spoutConf = <span class="hljs-keyword">new</span> PulsarSpoutConfiguration();
spoutConf.setServiceUrl(<span class="hljs-string">"pulsar://broker.messaging.usw.example.com:6650"</span>);
spoutConf.setTopic(<span class="hljs-string">"persistent://my-property/usw/my-ns/my-topic1"</span>);
spoutConf.setSubscriptionName(<span class="hljs-string">"my-subscriber-name1"</span>);
spoutConf.setMessageToValuesMapper(messageToValuesMapper);

<span class="hljs-comment">// Create a Pulsar Spout</span>
PulsarSpout spout = <span class="hljs-keyword">new</span> PulsarSpout(spoutConf);
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="pulsar-bolt"></a><a href="#pulsar-bolt" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Pulsar Bolt</h2>
<p>The Pulsar bolt allows data in a Storm topology to be published on a topic. It publishes messages based on the Storm tuple received and the <code>TupleToMessageMapper</code> provided by the client.</p>
<p>A partitioned topic can also be used to publish messages on different topics. In the implementation of the <code>TupleToMessageMapper</code>, a &quot;key&quot; will need to be provided in the message which will send the messages with the same key to the same topic. Here's an example bolt:</p>
<pre><code class="hljs css language-java">TupleToMessageMapper tupleToMessageMapper = <span class="hljs-keyword">new</span> TupleToMessageMapper() {

    <span class="hljs-meta">@Override</span>
    <span class="hljs-keyword">public</span> TypedMessageBuilder&lt;<span class="hljs-keyword">byte</span>[]&gt; toMessage(TypedMessageBuilder&lt;<span class="hljs-keyword">byte</span>[]&gt; msgBuilder, Tuple tuple) {
        String receivedMessage = tuple.getString(<span class="hljs-number">0</span>);
        <span class="hljs-comment">// message processing</span>
        String processedMsg = receivedMessage + <span class="hljs-string">"-processed"</span>;
        <span class="hljs-keyword">return</span> msgBuilder.value(processedMsg.getBytes());
    }

    <span class="hljs-meta">@Override</span>
    <span class="hljs-function"><span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">declareOutputFields</span><span class="hljs-params">(OutputFieldsDeclarer declarer)</span> </span>{
        <span class="hljs-comment">// declare the output fields</span>
    }
};

<span class="hljs-comment">// Configure a Pulsar Bolt</span>
PulsarBoltConfiguration boltConf = <span class="hljs-keyword">new</span> PulsarBoltConfiguration();
boltConf.setServiceUrl(<span class="hljs-string">"pulsar://broker.messaging.usw.example.com:6650"</span>);
boltConf.setTopic(<span class="hljs-string">"persistent://my-property/usw/my-ns/my-topic2"</span>);
boltConf.setTupleToMessageMapper(tupleToMessageMapper);

<span class="hljs-comment">// Create a Pulsar Bolt</span>
PulsarBolt bolt = <span class="hljs-keyword">new</span> PulsarBolt(boltConf);
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="example"></a><a href="#example" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Example</h2>
<p>You can find a complete example <a href="https://github.com/apache/pulsar/tree/master/pulsar-storm/src/test/java/org/apache/pulsar/storm/example/StormExample.java">here</a>.</p>
</span></div></article></div><div class="docs-prevnext"><a class="docs-prev button" href="/docs/en/2.3.1/adaptors-spark"><span class="arrow-prev">← </span><span>Apache Spark</span></a><a class="docs-next button" href="/docs/en/2.3.1/cookbooks-tiered-storage"><span>Tiered Storage</span><span class="arrow-next"> →</span></a></div></div></div><nav class="onPageNav"><ul class="toc-headings"><li><a href="#using-the-pulsar-storm-adaptor">Using the Pulsar Storm Adaptor</a></li><li><a href="#pulsar-spout">Pulsar Spout</a></li><li><a href="#pulsar-bolt">Pulsar Bolt</a></li><li><a href="#example">Example</a></li></ul></nav></div><footer class="nav-footer" id="footer"><section class="copyright">Copyright © 2022 The Apache Software Foundation. All Rights Reserved. Apache, Apache Pulsar and the Apache feather logo are trademarks of The Apache Software Foundation.</section><span><script>
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