<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Debug Pulsar Functions · Apache Pulsar</title><meta name="viewport" content="width=device-width, initial-scale=1.0"/><meta name="generator" content="Docusaurus"/><meta name="description" content="You can use the following methods to debug Pulsar Functions:"/><meta name="docsearch:version" content="2.4.2"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Debug Pulsar Functions · Apache Pulsar"/><meta property="og:type" content="website"/><meta property="og:url" content="https://pulsar.apache.org/"/><meta property="og:description" content="You can use the following methods to debug Pulsar Functions:"/><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>2.4.2</h3></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li class="siteNavGroupActive"><a href="/docs/en/2.4.2/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/2.4.2/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/2.4.2/functions-debug">日本語</a></li><li><a href="/docs/fr/2.4.2/functions-debug">Français</a></li><li><a href="/docs/ko/2.4.2/functions-debug">한국어</a></li><li><a href="/docs/zh-CN/2.4.2/functions-debug">中文</a></li><li><a href="/docs/zh-TW/2.4.2/functions-debug">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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class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-worker">Setup: Pulsar Functions Worker</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-runtime">Setup: Configure Functions runtime</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-develop">How-to: Develop</a></li><li class="navListItem navListItemActive"><a class="navItem" href="/docs/en/2.4.2/functions-debug">How-to: Debug</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-deploy">How-to: Deploy</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-cli">Reference: CLI</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/window-functions-context">Window Functions: Context</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Pulsar IO</h3><ul class=""><li 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<ul>
<li><a href="/docs/en/2.4.2/functions-debug#use-unit-test">Use unit test</a></li>
<li><a href="/docs/en/2.4.2/functions-debug#debug-with-localrun-mode">Debug with localrun mode</a></li>
<li><a href="/docs/en/2.4.2/functions-debug#use-log-topic">Use log topic</a></li>
<li><a href="/docs/en/2.4.2/functions-debug#use-functions-cli">Use Functions CLI</a></li>
</ul>
<h2><a class="anchor" aria-hidden="true" id="use-unit-test"></a><a href="#use-unit-test" 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>Use unit test</h2>
<p>A Pulsar Function is a function with inputs and outputs, you can test a Pulsar Function in a similar way as you test any function.</p>
<p>For example, if you have the following Pulsar Function:</p>
<pre><code class="hljs css language-java"><span class="hljs-keyword">import</span> java.util.function.Function;

<span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">JavaNativeExclamationFunction</span> <span class="hljs-keyword">implements</span> <span class="hljs-title">Function</span>&lt;<span class="hljs-title">String</span>, <span class="hljs-title">String</span>&gt; </span>{
   <span class="hljs-meta">@Override</span>
   <span class="hljs-function"><span class="hljs-keyword">public</span> String <span class="hljs-title">apply</span><span class="hljs-params">(String input)</span> </span>{
       <span class="hljs-keyword">return</span> String.format(<span class="hljs-string">"%s!"</span>, input);
   }
}
</code></pre>
<p>You can write a simple unit test to test Pulsar Function.</p>
<pre><code class="hljs css language-java"><span class="hljs-meta">@Test</span>
<span class="hljs-function"><span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">testJavaNativeExclamationFunction</span><span class="hljs-params">()</span> </span>{
   JavaNativeExclamationFunction exclamation = <span class="hljs-keyword">new</span> JavaNativeExclamationFunction();
   String output = exclamation.apply(<span class="hljs-string">"foo"</span>);
   Assert.assertEquals(output, <span class="hljs-string">"foo!"</span>);
}
</code></pre>
<p>The following Pulsar Function implements the <code>org.apache.pulsar.functions.api.Function</code> interface.</p>
<pre><code class="hljs css language-java"><span class="hljs-keyword">import</span> org.apache.pulsar.functions.api.Context;
<span class="hljs-keyword">import</span> org.apache.pulsar.functions.api.Function;

<span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">ExclamationFunction</span> <span class="hljs-keyword">implements</span> <span class="hljs-title">Function</span>&lt;<span class="hljs-title">String</span>, <span class="hljs-title">String</span>&gt; </span>{
   <span class="hljs-meta">@Override</span>
   <span class="hljs-function"><span class="hljs-keyword">public</span> String <span class="hljs-title">process</span><span class="hljs-params">(String input, Context context)</span> </span>{
       <span class="hljs-keyword">return</span> String.format(<span class="hljs-string">"%s!"</span>, input);
   }
}
</code></pre>
<p>In this situation, you can write a unit test for this function as well. Remember to mock the <code>Context</code> parameter. The following is an example.</p>
<pre><code class="hljs css language-java"><span class="hljs-meta">@Test</span>
<span class="hljs-function"><span class="hljs-keyword">public</span> <span class="hljs-keyword">void</span> <span class="hljs-title">testExclamationFunction</span><span class="hljs-params">()</span> </span>{
   ExclamationFunction exclamation = <span class="hljs-keyword">new</span> ExclamationFunction();
   String output = exclamation.process(<span class="hljs-string">"foo"</span>, mock(Context<span class="hljs-class">.<span class="hljs-keyword">class</span>))</span>;
   Assert.assertEquals(output, <span class="hljs-string">"foo!"</span>);
}
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="debug-with-localrun-mode"></a><a href="#debug-with-localrun-mode" 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>Debug with localrun mode</h2>
<p>When you run a Pulsar Function in localrun mode, it launches an instance of the Function on your local machine as a thread.</p>
<p>In this mode, a Pulsar Function consumes and produces actual data to a Pulsar cluster, and mirrors how the function actually runs in a Pulsar cluster.</p>
<blockquote>
<p>Note<br>
Currently, debugging with localrun mode is only supported by Pulsar Functions written in Java. You need Pulsar version 2.4.0 or later to do the following. Even though localrun is available in versions earlier than Pulsar 2.4.0, you cannot debug with localrun mode programmatically or run Functions as threads.</p>
</blockquote>
<p>You can launch your function in the following manner.</p>
<pre><code class="hljs css language-java">FunctionConfig functionConfig = <span class="hljs-keyword">new</span> FunctionConfig();
functionConfig.setName(functionName);
functionConfig.setInputs(Collections.singleton(sourceTopic));
functionConfig.setClassName(ExclamationFunction<span class="hljs-class">.<span class="hljs-keyword">class</span>.<span class="hljs-title">getName</span>())</span>;
functionConfig.setRuntime(FunctionConfig.Runtime.JAVA);
functionConfig.setOutput(sinkTopic);

LocalRunner localRunner = LocalRunner.builder().functionConfig(functionConfig).build();
localRunner.start(<span class="hljs-keyword">true</span>);
</code></pre>
<p>So you can debug functions using an IDE easily. Set breakpoints and manually step through a function to debug with real data.</p>
<p>The following example illustrates how to programmatically launch a function in localrun mode.</p>
<pre><code class="hljs css language-java"><span class="hljs-keyword">public</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">ExclamationFunction</span> <span class="hljs-keyword">implements</span> <span class="hljs-title">Function</span>&lt;<span class="hljs-title">String</span>, <span class="hljs-title">String</span>&gt; </span>{

   <span class="hljs-meta">@Override</span>
   <span class="hljs-function"><span class="hljs-keyword">public</span> String <span class="hljs-title">process</span><span class="hljs-params">(String s, Context context)</span> <span class="hljs-keyword">throws</span> Exception </span>{
       <span class="hljs-keyword">return</span> s + <span class="hljs-string">"!"</span>;
   }

<span class="hljs-function"><span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title">main</span><span class="hljs-params">(String[] args)</span> <span class="hljs-keyword">throws</span> Exception </span>{
    FunctionConfig functionConfig = <span class="hljs-keyword">new</span> FunctionConfig();
    functionConfig.setName(<span class="hljs-string">"exclamation"</span>);
    functionConfig.setInputs(Collections.singleton(<span class="hljs-string">"input"</span>));
    functionConfig.setClassName(ExclamationFunction<span class="hljs-class">.<span class="hljs-keyword">class</span>.<span class="hljs-title">getName</span>())</span>;
    functionConfig.setRuntime(FunctionConfig.Runtime.JAVA);
    functionConfig.setOutput(<span class="hljs-string">"output"</span>);

    LocalRunner localRunner = LocalRunner.builder().functionConfig(functionConfig).build();
    localRunner.start(<span class="hljs-keyword">false</span>);
}
</code></pre>
<p>To use localrun mode programmatically, add the following dependency.</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-functions-local-runner<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>
<p>For complete code samples, see <a href="https://github.com/jerrypeng/pulsar-functions-demos/tree/master/debugging">here</a>.</p>
<blockquote>
<p>Note<br>
Debugging with localrun mode for Pulsar Functions written in other languages will be supported soon.</p>
</blockquote>
<h2><a class="anchor" aria-hidden="true" id="use-log-topic"></a><a href="#use-log-topic" 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>Use log topic</h2>
<p>In Pulsar Functions, you can generate log information defined in functions to a specified log topic. You can configure consumers to consume messages from a specified log topic to check the log information.</p>
<p><img src="/docs/assets/pulsar-functions-overview.png" alt="Pulsar Functions core programming model"></p>
<p><strong>Example</strong></p>
<pre><code class="hljs css language-text">import org.apache.pulsar.functions.api.Context;
import org.apache.pulsar.functions.api.Function;
import org.slf4j.Logger;

public class LoggingFunction implements Function<String, Void> {
    @Override
    public void apply(String input, Context context) {
        Logger LOG = context.getLogger();
        String messageId = new String(context.getMessageId());

        if (input.contains("danger")) {
            LOG.warn("A warning was received in message {}", messageId);
        } else {
            LOG.info("Message {} received\nContent: {}", messageId, input);
        }

        return null;
    }
}
</code></pre>
<p>As shown in the example above, you can get the logger via <code>context.getLogger()</code> and assign the logger to the <code>LOG</code> variable of <code>slf4j</code>, so you can define your desired log information in a function using the <code>LOG</code> variable. Meanwhile, you need to specify the topic to which the log information is produced.</p>
<p><strong>Example</strong></p>
<pre><code class="hljs">$ bin/pulsar-admin functions create \
  --<span class="hljs-built_in">log</span>-topic persistent://<span class="hljs-keyword">public</span>/<span class="hljs-keyword">default</span>/logging-<span class="hljs-function"><span class="hljs-keyword">function</span></span>-logs \
  # Other <span class="hljs-function"><span class="hljs-keyword">function</span></span> configs
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="use-functions-cli"></a><a href="#use-functions-cli" 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>Use Functions CLI</h2>
<p>With <a href="/docs/en/2.4.2/reference-pulsar-admin#functions">Pulsar Functions CLI</a>, you can debug Pulsar Functions with the following subcommands:</p>
<ul>
<li><code>get</code></li>
<li><code>status</code></li>
<li><code>stats</code></li>
<li><code>list</code></li>
<li><code>trigger</code></li>
</ul>
<blockquote>
<p><strong>Tip</strong></p>
<p>For complete commands of <strong>Pulsar Functions CLI</strong>, see <a href="/docs/en/2.4.2/reference-pulsar-admin#functions">here</a>。</p>
</blockquote>
<h3><a class="anchor" aria-hidden="true" id="get"></a><a href="#get" 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><code>get</code></h3>
<p>Get information about a Pulsar Function.</p>
<p><strong>Usage</strong></p>
<pre><code class="hljs css language-text">$ pulsar-admin functions get options
</code></pre>
<p><strong>Options</strong></p>
<table>
<thead>
<tr><th>Flag</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>--fqfn</code></td><td>The Fully Qualified Function Name (FQFN) of a Pulsar Function.</td></tr>
<tr><td><code>--name</code></td><td>The name of a Pulsar Function.</td></tr>
<tr><td><code>--namespace</code></td><td>The namespace of a Pulsar Function.</td></tr>
<tr><td><code>--tenant</code></td><td>The tenant of a Pulsar Function.</td></tr>
</tbody>
</table>
<blockquote>
<p><strong>Tip</strong></p>
<p><code>--fqfn</code> consists of <code>--name</code>, <code>--namespace</code> and <code>--tenant</code>, so you can specify either <code>--fqfn</code> or <code>--name</code>, <code>--namespace</code> and <code>--tenant</code>.</p>
</blockquote>
<p><strong>Example</strong></p>
<p>You can specify <code>--fqfn</code> to get information about a Pulsar Function.</p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions get public/default/ExclamationFunctio6
</code></pre>
<p>Optionally, you can specify <code>--name</code>, <code>--namespace</code> and <code>--tenant</code> to get information about a Pulsar Function.</p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions get \
    --tenant public \
    --namespace default \
    --name ExclamationFunctio6
</code></pre>
<p>As shown below, the <code>get</code> command shows input, output, runtime, and other information about the <em>ExclamationFunctio6</em> function.</p>
<pre><code class="hljs css language-text">{
  "tenant": "public",
  "namespace": "default",
  "name": "ExclamationFunctio6",
  "className": "org.example.test.ExclamationFunction",
  "inputSpecs": {
    "persistent://public/default/my-topic-1": {
      "isRegexPattern": false
    }
  },
  "output": "persistent://public/default/test-1",
  "processingGuarantees": "ATLEAST_ONCE",
  "retainOrdering": false,
  "userConfig": {},
  "runtime": "JAVA",
  "autoAck": true,
  "parallelism": 1
}
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="status"></a><a href="#status" 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><code>status</code></h3>
<p>Check the current status of a Pulsar Function.</p>
<p><strong>Usage</strong></p>
<pre><code class="hljs css language-text">$ pulsar-admin functions status options
</code></pre>
<p><strong>Options</strong></p>
<table>
<thead>
<tr><th>Flag</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>--fqfn</code></td><td>The Fully Qualified Function Name (FQFN) of a Pulsar Function.</td></tr>
<tr><td><code>--instance-id</code></td><td>The instance ID of a Pulsar Function <br>If the <code>--instance-id</code> is not specified, it gets the IDs of all instances.<br></td></tr>
<tr><td><code>--name</code></td><td>The name of a Pulsar Function.</td></tr>
<tr><td><code>--namespace</code></td><td>The namespace of a Pulsar Function.</td></tr>
<tr><td><code>--tenant</code></td><td>The tenant of a Pulsar Function.</td></tr>
</tbody>
</table>
<p><strong>Example</strong></p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions status \
    --tenant public \
    --namespace default \
    --name ExclamationFunctio6 \
</code></pre>
<p>As shown below, the <code>status</code> command shows the number of instances, running instances, the instance running under the <em>ExclamationFunctio6</em> function, received messages, successfully processed messages, system exceptions, the average latency and so on.</p>
<pre><code class="hljs css language-text">{
  "numInstances" : 1,
  "numRunning" : 1,
  "instances" : [ {
    "instanceId" : 0,
    "status" : {
      "running" : true,
      "error" : "",
      "numRestarts" : 0,
      "numReceived" : 1,
      "numSuccessfullyProcessed" : 1,
      "numUserExceptions" : 0,
      "latestUserExceptions" : [ ],
      "numSystemExceptions" : 0,
      "latestSystemExceptions" : [ ],
      "averageLatency" : 0.8385,
      "lastInvocationTime" : 1557734137987,
      "workerId" : "c-standalone-fw-23ccc88ef29b-8080"
    }
  } ]
}
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="stats"></a><a href="#stats" 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><code>stats</code></h3>
<p>Get the current stats of a Pulsar Function.</p>
<p><strong>Usage</strong></p>
<pre><code class="hljs css language-text">$ pulsar-admin functions stats options
</code></pre>
<p><strong>Options</strong></p>
<table>
<thead>
<tr><th>Flag</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>--fqfn</code></td><td>The Fully Qualified Function Name (FQFN) of a Pulsar Function.</td></tr>
<tr><td><code>--instance-id</code></td><td>The instance ID of a Pulsar Function. <br>If the <code>--instance-id</code> is not specified, it gets the IDs of all instances.<br></td></tr>
<tr><td><code>--name</code></td><td>The name of a Pulsar Function.</td></tr>
<tr><td><code>--namespace</code></td><td>The namespace of a Pulsar Function.</td></tr>
<tr><td><code>--tenant</code></td><td>The tenant of a Pulsar Function.</td></tr>
</tbody>
</table>
<p><strong>Example</strong></p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions stats \
    --tenant public \
    --namespace default \
    --name ExclamationFunctio6 \
</code></pre>
<p>The output is shown as follows:</p>
<pre><code class="hljs css language-text">{
  "receivedTotal" : 1,
  "processedSuccessfullyTotal" : 1,
  "systemExceptionsTotal" : 0,
  "userExceptionsTotal" : 0,
  "avgProcessLatency" : 0.8385,
  "1min" : {
    "receivedTotal" : 0,
    "processedSuccessfullyTotal" : 0,
    "systemExceptionsTotal" : 0,
    "userExceptionsTotal" : 0,
    "avgProcessLatency" : null
  },
  "lastInvocation" : 1557734137987,
  "instances" : [ {
    "instanceId" : 0,
    "metrics" : {
      "receivedTotal" : 1,
      "processedSuccessfullyTotal" : 1,
      "systemExceptionsTotal" : 0,
      "userExceptionsTotal" : 0,
      "avgProcessLatency" : 0.8385,
      "1min" : {
        "receivedTotal" : 0,
        "processedSuccessfullyTotal" : 0,
        "systemExceptionsTotal" : 0,
        "userExceptionsTotal" : 0,
        "avgProcessLatency" : null
      },
      "lastInvocation" : 1557734137987,
      "userMetrics" : { }
    }
  } ]
}
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="list"></a><a href="#list" 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><code>list</code></h3>
<p>List all Pulsar Functions running under a specific tenant and namespace.</p>
<p><strong>Usage</strong></p>
<pre><code class="hljs css language-text">$ pulsar-admin functions list options
</code></pre>
<p><strong>Options</strong></p>
<table>
<thead>
<tr><th>Flag</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>--namespace</code></td><td>The namespace of a Pulsar Function.</td></tr>
<tr><td><code>--tenant</code></td><td>The tenant of a Pulsar Function.</td></tr>
</tbody>
</table>
<p><strong>Example</strong></p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions list \
    --tenant public \
    --namespace default
</code></pre>
<p>As shown below, the <code>list</code> command returns three functions running under the <em>public</em> tenant and the <em>default</em> namespace.</p>
<pre><code class="hljs css language-text">ExclamationFunctio1
ExclamationFunctio2
ExclamationFunctio3
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="trigger"></a><a href="#trigger" 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><code>trigger</code></h3>
<p>Trigger a specified Pulsar Function with a supplied value. This command simulates the execution process of a Pulsar Function and verifies it.</p>
<p><strong>Usage</strong></p>
<pre><code class="hljs css language-text">$ pulsar-admin functions trigger options
</code></pre>
<p><strong>Options</strong></p>
<table>
<thead>
<tr><th>Flag</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>--fqfn</code></td><td>The Fully Qualified Function Name (FQFN) of a Pulsar Function.</td></tr>
<tr><td><code>--name</code></td><td>The name of a Pulsar Function.</td></tr>
<tr><td><code>--namespace</code></td><td>The namespace of a Pulsar Function.</td></tr>
<tr><td><code>--tenant</code></td><td>The tenant of a Pulsar Function.</td></tr>
<tr><td><code>--topic</code></td><td>The topic name that a Pulsar Function consumes from.</td></tr>
<tr><td><code>--trigger-file</code></td><td>The path to a file that contains the data to trigger a Pulsar Function.</td></tr>
<tr><td><code>--trigger-value</code></td><td>The value to trigger a Pulsar Function.</td></tr>
</tbody>
</table>
<p><strong>Example</strong></p>
<pre><code class="hljs css language-text">$ ./bin/pulsar-admin functions trigger \
    --tenant public \
    --namespace default \
    --name ExclamationFunctio6 \
    --topic persistent://public/default/my-topic-1 \
    --trigger-value "hello pulsar functions"
</code></pre>
<p>As shown below, the <code>trigger</code> command returns the following result:</p>
<pre><code class="hljs css language-text">This is my function!
</code></pre>
<blockquote>
<h4><a class="anchor" aria-hidden="true" id="note"></a><a href="#note" 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><strong>Note</strong></h4>
<p>You must specify the <a href="/docs/en/2.4.2/pulsar-2.0#topic-names">entire topic name</a> when using the <code>--topic</code> option. Otherwise, the following error occurs.</p>
<pre><code class="hljs css language-text">Function in trigger function has unidentified topic

Reason: Function in trigger function has unidentified topic
</code></pre>
</blockquote>
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