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href="#event-inspector-protocol-method">Event: <code><inspector-protocol-method></code>;</a></li> 135<li><a href="#sessionconnect"><code>session.connect()</code></a></li> 136<li><a href="#sessionconnecttomainthread"><code>session.connectToMainThread()</code></a></li> 137<li><a href="#sessiondisconnect"><code>session.disconnect()</code></a></li> 138<li><a href="#sessionpostmethod-params-callback"><code>session.post(method[, params][, callback])</code></a> 139<ul> 140<li><a href="#example-usage">Example usage</a></li> 141</ul> 142</li> 143<li><a href="#cpu-profiler">CPU profiler</a></li> 144<li><a href="#heap-profiler">Heap profiler</a></li> 145</ul> 146</li> 147</ul> 148</li> 149</ul></div></div> 150 </li> 151 152 153 <li class="picker-header"> 154 <a href="#"> 155 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 156 Index 157 </a> 158 159 <div class="picker"><ul> 160<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> 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class="nav-querystring">Query strings</a></li> 209<li><a href="readline.html" class="nav-readline">Readline</a></li> 210<li><a href="repl.html" class="nav-repl">REPL</a></li> 211<li><a href="report.html" class="nav-report">Report</a></li> 212<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li> 213<li><a href="stream.html" class="nav-stream">Stream</a></li> 214<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> 215<li><a href="test.html" class="nav-test">Test runner</a></li> 216<li><a href="timers.html" class="nav-timers">Timers</a></li> 217<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> 218<li><a href="tracing.html" class="nav-tracing">Trace events</a></li> 219<li><a href="tty.html" class="nav-tty">TTY</a></li> 220<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> 221<li><a href="url.html" class="nav-url">URL</a></li> 222<li><a href="util.html" class="nav-util">Utilities</a></li> 223<li><a href="v8.html" class="nav-v8">V8</a></li> 224<li><a href="vm.html" class="nav-vm">VM</a></li> 225<li><a href="wasi.html" class="nav-wasi">WASI</a></li> 226<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> 227<li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li> 228<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> 229<li><a href="zlib.html" class="nav-zlib">Zlib</a></li> 230</ul> 231<hr class="line"> 232<ul> 233<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> 234</ul></div> 235 </li> 236 237 238 <li class="picker-header"> 239 <a href="#"> 240 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 241 Other versions 242 </a> 243 <div class="picker"><ol id="alt-docs"><li><a href="https://nodejs.org/docs/latest-v21.x/api/inspector.html">21.x</a></li> 244<li><a href="https://nodejs.org/docs/latest-v20.x/api/inspector.html">20.x <b>LTS</b></a></li> 245<li><a href="https://nodejs.org/docs/latest-v19.x/api/inspector.html">19.x</a></li> 246<li><a href="https://nodejs.org/docs/latest-v18.x/api/inspector.html">18.x <b>LTS</b></a></li> 247<li><a href="https://nodejs.org/docs/latest-v17.x/api/inspector.html">17.x</a></li> 248<li><a href="https://nodejs.org/docs/latest-v16.x/api/inspector.html">16.x</a></li> 249<li><a href="https://nodejs.org/docs/latest-v15.x/api/inspector.html">15.x</a></li> 250<li><a href="https://nodejs.org/docs/latest-v14.x/api/inspector.html">14.x</a></li> 251<li><a href="https://nodejs.org/docs/latest-v13.x/api/inspector.html">13.x</a></li> 252<li><a href="https://nodejs.org/docs/latest-v12.x/api/inspector.html">12.x</a></li> 253<li><a href="https://nodejs.org/docs/latest-v11.x/api/inspector.html">11.x</a></li> 254<li><a href="https://nodejs.org/docs/latest-v10.x/api/inspector.html">10.x</a></li> 255<li><a href="https://nodejs.org/docs/latest-v9.x/api/inspector.html">9.x</a></li> 256<li><a href="https://nodejs.org/docs/latest-v8.x/api/inspector.html">8.x</a></li></ol></div> 257 </li> 258 259 <li class="picker-header"> 260 <a href="#"> 261 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 262 Options 263 </a> 264 265 <div class="picker"> 266 <ul> 267 <li> 268 <a href="all.html">View on single page</a> 269 </li> 270 <li> 271 <a href="inspector.json">View as JSON</a> 272 </li> 273 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/inspector.md">Edit on GitHub</a></li> 274 </ul> 275 </div> 276 </li> 277 </ul> 278 </div> 279 <hr> 280 </header> 281 282 <details id="toc" open><summary>Table of contents</summary><ul> 283<li><span class="stability_2"><a href="#inspector">Inspector</a></span> 284<ul> 285<li><a href="#inspectorclose"><code>inspector.close()</code></a></li> 286<li><a href="#inspectorconsole"><code>inspector.console</code></a></li> 287<li><a href="#inspectoropenport-host-wait"><code>inspector.open([port[, host[, wait]]])</code></a></li> 288<li><a href="#inspectorurl"><code>inspector.url()</code></a></li> 289<li><a href="#inspectorwaitfordebugger"><code>inspector.waitForDebugger()</code></a></li> 290<li><a href="#class-inspectorsession">Class: <code>inspector.Session</code></a> 291<ul> 292<li><a href="#new-inspectorsession"><code>new inspector.Session()</code></a></li> 293<li><a href="#event-inspectornotification">Event: <code>'inspectorNotification'</code></a></li> 294<li><a href="#event-inspector-protocol-method">Event: <code><inspector-protocol-method></code>;</a></li> 295<li><a href="#sessionconnect"><code>session.connect()</code></a></li> 296<li><a href="#sessionconnecttomainthread"><code>session.connectToMainThread()</code></a></li> 297<li><a href="#sessiondisconnect"><code>session.disconnect()</code></a></li> 298<li><a href="#sessionpostmethod-params-callback"><code>session.post(method[, params][, callback])</code></a> 299<ul> 300<li><a href="#example-usage">Example usage</a></li> 301</ul> 302</li> 303<li><a href="#cpu-profiler">CPU profiler</a></li> 304<li><a href="#heap-profiler">Heap profiler</a></li> 305</ul> 306</li> 307</ul> 308</li> 309</ul></details> 310 311 <div id="apicontent"> 312 <h2>Inspector<span><a class="mark" href="#inspector" id="inspector">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector"></a></h2> 313 314<p></p><div class="api_stability api_stability_2"><a href="documentation.html#stability-index">Stability: 2</a> - Stable</div><p></p> 315<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v18.20.1/lib/inspector.js">lib/inspector.js</a></p> 316<p>The <code>node:inspector</code> module provides an API for interacting with the V8 317inspector.</p> 318<p>It can be accessed using:</p> 319<pre><code class="language-js"><span class="hljs-keyword">const</span> inspector = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:inspector'</span>);</code> <button class="copy-button">copy</button></pre> 320<section><h3><code>inspector.close()</code><span><a class="mark" href="#inspectorclose" id="inspectorclose">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector_close"></a></h3> 321<div class="api_metadata"> 322<details class="changelog"><summary>History</summary> 323<table> 324<tbody><tr><th>Version</th><th>Changes</th></tr> 325<tr><td>v18.10.0</td> 326<td><p>The API is exposed in the worker threads.</p></td></tr> 327<tr><td>v9.0.0</td> 328<td><p><span>Added in: v9.0.0</span></p></td></tr> 329</tbody></table> 330</details> 331</div> 332<p>Deactivate the inspector. Blocks until there are no active connections.</p> 333<p>When using <code>Session</code>, the object outputted by the console API will not be 334released, unless we performed manually <code>Runtime.DiscardConsoleEntries</code> 335command.</p> 336</section><section><h3><code>inspector.console</code><span><a class="mark" href="#inspectorconsole" id="inspectorconsole">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector_console"></a></h3> 337<ul> 338<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> An object to send messages to the remote inspector console.</li> 339</ul> 340<pre><code class="language-js"><span class="hljs-built_in">require</span>(<span class="hljs-string">'node:inspector'</span>).<span class="hljs-property">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'a message'</span>);</code> <button class="copy-button">copy</button></pre> 341<p>The inspector console does not have API parity with Node.js 342console.</p> 343</section><section><h3><code>inspector.open([port[, host[, wait]]])</code><span><a class="mark" href="#inspectoropenport-host-wait" id="inspectoropenport-host-wait">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector_open_port_host_wait"></a></h3> 344<ul> 345<li><code>port</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Port to listen on for inspector connections. Optional. 346<strong>Default:</strong> what was specified on the CLI.</li> 347<li><code>host</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Host to listen on for inspector connections. Optional. 348<strong>Default:</strong> what was specified on the CLI.</li> 349<li><code>wait</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Block until a client has connected. Optional. 350<strong>Default:</strong> <code>false</code>.</li> 351</ul> 352<p>Activate inspector on host and port. Equivalent to 353<code>node --inspect=[[host:]port]</code>, but can be done programmatically after node has 354started.</p> 355<p>If wait is <code>true</code>, will block until a client has connected to the inspect port 356and flow control has been passed to the debugger client.</p> 357<p>See the <a href="cli.html#warning-binding-inspector-to-a-public-ipport-combination-is-insecure">security warning</a> regarding the <code>host</code> 358parameter usage.</p> 359</section><section><h3><code>inspector.url()</code><span><a class="mark" href="#inspectorurl" id="inspectorurl">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector_url"></a></h3> 360<ul> 361<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 362</ul> 363<p>Return the URL of the active inspector, or <code>undefined</code> if there is none.</p> 364<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">node --inspect -p <span class="hljs-string">'inspector.url()'</span></span> 365Debugger listening on ws://127.0.0.1:9229/166e272e-7a30-4d09-97ce-f1c012b43c34 366For help, see: https://nodejs.org/en/docs/inspector 367ws://127.0.0.1:9229/166e272e-7a30-4d09-97ce-f1c012b43c34 368<span class="hljs-meta prompt_"> 369$ </span><span class="language-bash">node --inspect=localhost:3000 -p <span class="hljs-string">'inspector.url()'</span></span> 370Debugger listening on ws://localhost:3000/51cf8d0e-3c36-4c59-8efd-54519839e56a 371For help, see: https://nodejs.org/en/docs/inspector 372ws://localhost:3000/51cf8d0e-3c36-4c59-8efd-54519839e56a 373<span class="hljs-meta prompt_"> 374$ </span><span class="language-bash">node -p <span class="hljs-string">'inspector.url()'</span></span> 375undefined</code> <button class="copy-button">copy</button></pre> 376</section><section><h3><code>inspector.waitForDebugger()</code><span><a class="mark" href="#inspectorwaitfordebugger" id="inspectorwaitfordebugger">#</a></span><a aria-hidden="true" class="legacy" id="inspector_inspector_waitfordebugger"></a></h3> 377<div class="api_metadata"> 378<span>Added in: v12.7.0</span> 379</div> 380<p>Blocks until a client (existing or connected later) has sent 381<code>Runtime.runIfWaitingForDebugger</code> command.</p> 382<p>An exception will be thrown if there is no active inspector.</p> 383</section><section><h3>Class: <code>inspector.Session</code><span><a class="mark" href="#class-inspectorsession" id="class-inspectorsession">#</a></span><a aria-hidden="true" class="legacy" id="inspector_class_inspector_session"></a></h3> 384<ul> 385<li>Extends: <a href="events.html#class-eventemitter" class="type"><EventEmitter></a></li> 386</ul> 387<p>The <code>inspector.Session</code> is used for dispatching messages to the V8 inspector 388back-end and receiving message responses and notifications.</p> 389<h4><code>new inspector.Session()</code><span><a class="mark" href="#new-inspectorsession" id="new-inspectorsession">#</a></span><a aria-hidden="true" class="legacy" id="inspector_new_inspector_session"></a></h4> 390<div class="api_metadata"> 391<span>Added in: v8.0.0</span> 392</div> 393<p>Create a new instance of the <code>inspector.Session</code> class. The inspector session 394needs to be connected through <a href="#sessionconnect"><code>session.connect()</code></a> before the messages 395can be dispatched to the inspector backend.</p> 396<p>When using <code>Session</code>, the object outputted by the console API will not be 397released, unless we performed manually <code>Runtime.DiscardConsoleEntries</code> 398command.</p> 399<h4>Event: <code>'inspectorNotification'</code><span><a class="mark" href="#event-inspectornotification" id="event-inspectornotification">#</a></span><a aria-hidden="true" class="legacy" id="inspector_event_inspectornotification"></a></h4> 400<div class="api_metadata"> 401<span>Added in: v8.0.0</span> 402</div> 403<ul> 404<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> The notification message object</li> 405</ul> 406<p>Emitted when any notification from the V8 Inspector is received.</p> 407<pre><code class="language-js">session.<span class="hljs-title function_">on</span>(<span class="hljs-string">'inspectorNotification'</span>, <span class="hljs-function">(<span class="hljs-params">message</span>) =></span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(message.<span class="hljs-property">method</span>)); 408<span class="hljs-comment">// Debugger.paused</span> 409<span class="hljs-comment">// Debugger.resumed</span></code> <button class="copy-button">copy</button></pre> 410<p>It is also possible to subscribe only to notifications with specific method:</p> 411<h4>Event: <code><inspector-protocol-method></code>;<span><a class="mark" href="#event-inspector-protocol-method" id="event-inspector-protocol-method">#</a></span><a aria-hidden="true" class="legacy" id="inspector_event_inspector_protocol_method"></a></h4> 412<div class="api_metadata"> 413<span>Added in: v8.0.0</span> 414</div> 415<ul> 416<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> The notification message object</li> 417</ul> 418<p>Emitted when an inspector notification is received that has its method field set 419to the <code><inspector-protocol-method></code> value.</p> 420<p>The following snippet installs a listener on the <a href="https://chromedevtools.github.io/devtools-protocol/v8/Debugger#event-paused"><code>'Debugger.paused'</code></a> 421event, and prints the reason for program suspension whenever program 422execution is suspended (through breakpoints, for example):</p> 423<pre><code class="language-js">session.<span class="hljs-title function_">on</span>(<span class="hljs-string">'Debugger.paused'</span>, <span class="hljs-function">(<span class="hljs-params">{ params }</span>) =></span> { 424 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(params.<span class="hljs-property">hitBreakpoints</span>); 425}); 426<span class="hljs-comment">// [ '/the/file/that/has/the/breakpoint.js:11:0' ]</span></code> <button class="copy-button">copy</button></pre> 427<h4><code>session.connect()</code><span><a class="mark" href="#sessionconnect" id="sessionconnect">#</a></span><a aria-hidden="true" class="legacy" id="inspector_session_connect"></a></h4> 428<div class="api_metadata"> 429<span>Added in: v8.0.0</span> 430</div> 431<p>Connects a session to the inspector back-end.</p> 432<h4><code>session.connectToMainThread()</code><span><a class="mark" href="#sessionconnecttomainthread" id="sessionconnecttomainthread">#</a></span><a aria-hidden="true" class="legacy" id="inspector_session_connecttomainthread"></a></h4> 433<div class="api_metadata"> 434<span>Added in: v12.11.0</span> 435</div> 436<p>Connects a session to the main thread inspector back-end. An exception will 437be thrown if this API was not called on a Worker thread.</p> 438<h4><code>session.disconnect()</code><span><a class="mark" href="#sessiondisconnect" id="sessiondisconnect">#</a></span><a aria-hidden="true" class="legacy" id="inspector_session_disconnect"></a></h4> 439<div class="api_metadata"> 440<span>Added in: v8.0.0</span> 441</div> 442<p>Immediately close the session. All pending message callbacks will be called 443with an error. <a href="#sessionconnect"><code>session.connect()</code></a> will need to be called to be able to send 444messages again. Reconnected session will lose all inspector state, such as 445enabled agents or configured breakpoints.</p> 446<h4><code>session.post(method[, params][, callback])</code><span><a class="mark" href="#sessionpostmethod-params-callback" id="sessionpostmethod-params-callback">#</a></span><a aria-hidden="true" class="legacy" id="inspector_session_post_method_params_callback"></a></h4> 447<div class="api_metadata"> 448<details class="changelog"><summary>History</summary> 449<table> 450<tbody><tr><th>Version</th><th>Changes</th></tr> 451<tr><td>v18.0.0</td> 452<td><p>Passing an invalid callback to the <code>callback</code> argument now throws <code>ERR_INVALID_ARG_TYPE</code> instead of <code>ERR_INVALID_CALLBACK</code>.</p></td></tr> 453<tr><td>v8.0.0</td> 454<td><p><span>Added in: v8.0.0</span></p></td></tr> 455</tbody></table> 456</details> 457</div> 458<ul> 459<li><code>method</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 460<li><code>params</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 461<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 462</ul> 463<p>Posts a message to the inspector back-end. <code>callback</code> will be notified when 464a response is received. <code>callback</code> is a function that accepts two optional 465arguments: error and message-specific result.</p> 466<pre><code class="language-js">session.<span class="hljs-title function_">post</span>(<span class="hljs-string">'Runtime.evaluate'</span>, { <span class="hljs-attr">expression</span>: <span class="hljs-string">'2 + 2'</span> }, 467 <span class="hljs-function">(<span class="hljs-params">error, { result }</span>) =></span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(result)); 468<span class="hljs-comment">// Output: { type: 'number', value: 4, description: '4' }</span></code> <button class="copy-button">copy</button></pre> 469<p>The latest version of the V8 inspector protocol is published on the 470<a href="https://chromedevtools.github.io/devtools-protocol/v8/">Chrome DevTools Protocol Viewer</a>.</p> 471<p>Node.js inspector supports all the Chrome DevTools Protocol domains declared 472by V8. Chrome DevTools Protocol domain provides an interface for interacting 473with one of the runtime agents used to inspect the application state and listen 474to the run-time events.</p> 475<p>You can not set <code>reportProgress</code> to <code>true</code> when sending a 476<code>HeapProfiler.takeHeapSnapshot</code> or <code>HeapProfiler.stopTrackingHeapObjects</code> 477command to V8.</p> 478<h5>Example usage<span><a class="mark" href="#example-usage" id="example-usage">#</a></span><a aria-hidden="true" class="legacy" id="inspector_example_usage"></a></h5> 479<p>Apart from the debugger, various V8 Profilers are available through the DevTools 480protocol.</p> 481<h4>CPU profiler<span><a class="mark" href="#cpu-profiler" id="cpu-profiler">#</a></span><a aria-hidden="true" class="legacy" id="inspector_cpu_profiler"></a></h4> 482<p>Here's an example showing how to use the <a href="https://chromedevtools.github.io/devtools-protocol/v8/Profiler">CPU Profiler</a>:</p> 483<pre><code class="language-js"><span class="hljs-keyword">const</span> inspector = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:inspector'</span>); 484<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:fs'</span>); 485<span class="hljs-keyword">const</span> session = <span class="hljs-keyword">new</span> inspector.<span class="hljs-title class_">Session</span>(); 486session.<span class="hljs-title function_">connect</span>(); 487 488session.<span class="hljs-title function_">post</span>(<span class="hljs-string">'Profiler.enable'</span>, <span class="hljs-function">() =></span> { 489 session.<span class="hljs-title function_">post</span>(<span class="hljs-string">'Profiler.start'</span>, <span class="hljs-function">() =></span> { 490 <span class="hljs-comment">// Invoke business logic under measurement here...</span> 491 492 <span class="hljs-comment">// some time later...</span> 493 session.<span class="hljs-title function_">post</span>(<span class="hljs-string">'Profiler.stop'</span>, <span class="hljs-function">(<span class="hljs-params">err, { profile }</span>) =></span> { 494 <span class="hljs-comment">// Write profile to disk, upload, etc.</span> 495 <span class="hljs-keyword">if</span> (!err) { 496 fs.<span class="hljs-title function_">writeFileSync</span>(<span class="hljs-string">'./profile.cpuprofile'</span>, <span class="hljs-title class_">JSON</span>.<span class="hljs-title function_">stringify</span>(profile)); 497 } 498 }); 499 }); 500});</code> <button class="copy-button">copy</button></pre> 501<h4>Heap profiler<span><a class="mark" href="#heap-profiler" id="heap-profiler">#</a></span><a aria-hidden="true" class="legacy" id="inspector_heap_profiler"></a></h4> 502<p>Here's an example showing how to use the <a href="https://chromedevtools.github.io/devtools-protocol/v8/HeapProfiler">Heap Profiler</a>:</p> 503<pre><code class="language-js"><span class="hljs-keyword">const</span> inspector = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:inspector'</span>); 504<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:fs'</span>); 505<span class="hljs-keyword">const</span> session = <span class="hljs-keyword">new</span> inspector.<span class="hljs-title class_">Session</span>(); 506 507<span class="hljs-keyword">const</span> fd = fs.<span class="hljs-title function_">openSync</span>(<span class="hljs-string">'profile.heapsnapshot'</span>, <span class="hljs-string">'w'</span>); 508 509session.<span class="hljs-title function_">connect</span>(); 510 511session.<span class="hljs-title function_">on</span>(<span class="hljs-string">'HeapProfiler.addHeapSnapshotChunk'</span>, <span class="hljs-function">(<span class="hljs-params">m</span>) =></span> { 512 fs.<span class="hljs-title function_">writeSync</span>(fd, m.<span class="hljs-property">params</span>.<span class="hljs-property">chunk</span>); 513}); 514 515session.<span class="hljs-title function_">post</span>(<span class="hljs-string">'HeapProfiler.takeHeapSnapshot'</span>, <span class="hljs-literal">null</span>, <span class="hljs-function">(<span class="hljs-params">err, r</span>) =></span> { 516 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'HeapProfiler.takeHeapSnapshot done:'</span>, err, r); 517 session.<span class="hljs-title function_">disconnect</span>(); 518 fs.<span class="hljs-title function_">closeSync</span>(fd); 519});</code> <button class="copy-button">copy</button></pre></section> 520 <!-- API END --> 521 </div> 522 </div> 523 </div> 524</body> 525</html> 526