| For more information, see <a href="https://github.com/apache/pulsar/blob/master/pip/pip-318.md" target="_blank" rel="noopener noreferrer">PIP-318</a>.</p></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="when-should-i-use-compacted-topics">When should I use compacted topics?<a href="#when-should-i-use-compacted-topics" class="hash-link" aria-label="Direct link to When should I use compacted topics?" title="Direct link to When should I use compacted topics?"></a></h2><p>The classic example of a topic that could benefit from compaction would be a stock ticker topic through which consumers can access up-to-date values for specific stocks. Imagine a scenario in which messages carrying stock value data use the stock symbol as the key (<code>GOOG</code>, <code>AAPL</code>, <code>TWTR</code>, etc.). Compacting this topic would give consumers on the topic two options:</p><ul><li>They can read from the "original," non-compacted topic in case they need access to "historical" values, i.e. the entirety of the topic's messages.</li><li>They can read from the compacted topic if they only want to see the most up-to-date messages.</li></ul><p>Thus, if you're using a Pulsar topic called <code>stock-values</code>, some consumers could have access to all messages in the topic (perhaps because they're performing some kind of number crunching of all values in the last hour) while the consumers used to power the real-time stock ticker only see the compacted topic (and thus aren't forced to process outdated messages). Which variant of the topic any given consumer pulls messages from is determined by the consumer's <a href="#configure-consumers">configuration</a>.</p><blockquote><p>One of the benefits of compaction in Pulsar is that you aren't forced to choose between compacted and non-compacted topics, as the compaction process leaves the original topic as-is and essentially adds an alternate topic. In other words, you can run compaction on a topic and consumers that need access to the non-compacted version of the topic will not be adversely affected.</p></blockquote><h2 class="anchor anchorWithStickyNavbar_LWe7" id="configure-compaction-to-run-automatically">Configure compaction to run automatically<a href="#configure-compaction-to-run-automatically" class="hash-link" aria-label="Direct link to Configure compaction to run automatically" title="Direct link to Configure compaction to run automatically"></a></h2><p>Compaction policy specifies how large the topic backlog can grow before compaction is triggered.</p><p>Tenant administrators can configure a compaction policy at namespace or topic levels. Configuring the compaction policy at the namespace level applies to all topics within that namespace.</p><p>For example, to trigger compaction in a namespace when the backlog reaches 100MB:</p><div class="language-bash codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-bash codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">bin/pulsar-admin namespaces set-compaction-threshold </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--threshold 100M my-tenant/my-namespace</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="trigger-compaction-manually">Trigger compaction manually<a href="#trigger-compaction-manually" class="hash-link" aria-label="Direct link to Trigger compaction manually" title="Direct link to Trigger compaction manually"></a></h2><p>To run compaction on a topic, you need to use the <a href="/reference/#/next/pulsar-admin/topics?id=compact" target="_blank" rel="noopener noreferrer"><code>topics compact</code></a> command for the <a href="/reference/#/next/pulsar-admin/" target="_blank" rel="noopener noreferrer"><code>pulsar-admin</code></a> CLI tool. Here's an example:</p><div class="language-bash codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-bash codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">bin/pulsar-admin topics compact </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">persistent://my-tenant/my-namespace/my-topic</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>The <code>pulsar-admin</code> tool runs compaction via the Pulsar <a href="https://pulsar.apache.org/admin-rest-api#/" target="_blank" rel="noopener noreferrer">REST</a> API. To run compaction in its own dedicated process, i.e. <em>not</em> through the REST API, you can use the <a href="/docs/next/reference-cli-tools/"><code>pulsar compact-topic</code></a> command. Here's an example:</p><div class="language-bash codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-bash codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">bin/pulsar compact-topic </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--topic persistent://my-tenant-namespace/my-topic</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><blockquote><p>Running compaction in its own process is recommended when you want to avoid interfering with the broker's performance. Broker performance should only be affected, however, when running compaction on topics with a large keyspace (i.e when there are many keys on the topic). The first phase of the compaction process keeps a copy of each key in the topic, which can create memory pressure as the number of keys grows. Using the <code>pulsar-admin topics compact</code> command to run compaction through the REST API should present no issues in the overwhelming majority of cases; using <code>pulsar compact-topic</code> should correspondingly be considered an edge case.</p></blockquote><p>The <code>pulsar compact-topic</code> command communicates with <a href="https://zookeeper.apache.org" target="_blank" rel="noopener noreferrer">ZooKeeper</a> directly. To establish communication with ZooKeeper, though, the <code>pulsar</code> CLI tool will need to have a valid <a href="/docs/next/reference-configuration/#broker">broker configuration</a>. You can either supply a proper configuration in <code>conf/broker.conf</code> or specify a non-default location for the configuration:</p><div class="language-bash codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-bash codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">bin/pulsar compact-topic </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--broker-conf /path/to/broker.conf </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--topic persistent://my-tenant/my-namespace/my-topic</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)"># If the configuration is in conf/broker.conf</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">bin/pulsar compact-topic </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--topic persistent://my-tenant/my-namespace/my-topic</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><div class="theme-admonition theme-admonition-tip alert alert--success admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 12 16"><path fill-rule="evenodd" d="M6.5 0C3.48 0 1 2.19 1 5c0 .92.55 2.25 1 3 1.34 2.25 1.78 2.78 2 4v1h5v-1c.22-1.22.66-1.75 2-4 .45-.75 1-2.08 1-3 0-2.81-2.48-5-5.5-5zm3.64 7.48c-.25.44-.47.8-.67 1.11-.86 1.41-1.25 2.06-1.45 3.23-.02.05-.02.11-.02.17H5c0-.06 0-.13-.02-.17-.2-1.17-.59-1.83-1.45-3.23-.2-.31-.42-.67-.67-1.11C2.44 6.78 2 5.65 2 5c0-2.2 2.02-4 4.5-4 1.22 0 2.36.42 3.22 1.19C10.55 2.94 11 3.94 11 5c0 .66-.44 1.78-.86 2.48zM4 14h5c-.23 1.14-1.3 2-2.5 2s-2.27-.86-2.5-2z"></path></svg></span>tip</div><div class="admonitionContent_S0QG"><p>The frequency to trigger topic compaction varies widely based on use cases. If you want a compacted topic to be extremely speedy on read, then you need to run compaction fairly frequently.</p></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="configure-consumers">Configure consumers<a href="#configure-consumers" class="hash-link" aria-label="Direct link to Configure consumers" title="Direct link to Configure consumers"></a></h2><p>Pulsar consumers and readers need to be configured to read from compacted topics. The section below introduces how to enable compacted topic reads for Java clients.</p><p>To read from a compacted topic using a Java consumer, the <code>readCompacted</code> parameter must be set to <code>true</code>. Here's an example consumer for a compacted topic:</p><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token class-name">Consumer</span><span class="token operator"><</span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">byte</span><span class="token punctuation" style="color:rgb(248, 248, 242)">[</span><span class="token punctuation" style="color:rgb(248, 248, 242)">]</span><span class="token operator">></span><span class="token plain"> compactedTopicConsumer </span><span class="token operator">=</span><span class="token plain"> client</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">newConsumer</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">topic</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">"some-compacted-topic"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">readCompacted</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>As mentioned above, topic compaction in Pulsar works on a <em>per-key basis</em>. That means that messages that you produce on compacted topics need to have keys (the content of the key will depend on your use case). Messages that don't have keys will be ignored by the compaction process. Here's an example Pulsar message with a key:</p><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token import namespace">org</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">apache</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">pulsar</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">client</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">api</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import class-name">TypedMessageBuilder</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token class-name">TypedMessageBuilder</span><span class="token operator"><</span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">byte</span><span class="token punctuation" style="color:rgb(248, 248, 242)">[</span><span class="token punctuation" style="color:rgb(248, 248, 242)">]</span><span class="token operator">></span><span class="token plain"> msg </span><span class="token operator">=</span><span class="token plain"> producer</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">newMessage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">key</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">"some-key"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">value</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">someByteArray</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>The example below shows a message with a key being produced on a compacted Pulsar topic:</p><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token import namespace">org</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">apache</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">pulsar</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">client</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">api</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import class-name">Producer</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token import namespace">org</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">apache</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">pulsar</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">client</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import namespace">api</span><span class="token import namespace punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token import class-name">PulsarClient</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token class-name">PulsarClient</span><span class="token plain"> client </span><span class="token operator">=</span><span class="token plain"> </span><span class="token class-name">PulsarClient</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">builder</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">serviceUrl</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">"pulsar://localhost:6650"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">build</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token class-name">Producer</span><span class="token operator"><</span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">byte</span><span class="token punctuation" style="color:rgb(248, 248, 242)">[</span><span class="token punctuation" style="color:rgb(248, 248, 242)">]</span><span class="token operator">></span><span class="token plain"> compactedTopicProducer </span><span class="token operator">=</span><span class="token plain"> client</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">newProducer</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">topic</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">"some-compacted-topic"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">create</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">compactedTopicProducer</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">newMessage</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">key</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">"some-key"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">value</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">someByteArray</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">send</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="theme-doc-footer-edit-meta-row row"><div class="col"><a 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