{ "type": "module", "source": "doc/api/report.md", "introduced_in": "v11.8.0", "stability": 2, "stabilityText": "Stable", "miscs": [ { "textRaw": "Diagnostic report", "name": "report", "introduced_in": "v11.8.0", "type": "misc", "stability": 2, "stabilityText": "Stable", "desc": "<p>Delivers a JSON-formatted diagnostic summary, written to a file.</p>\n<p>The report is intended for development, test, and production use, to capture\nand preserve information for problem determination. It includes JavaScript\nand native stack traces, heap statistics, platform information, resource\nusage etc. With the report option enabled, diagnostic reports can be triggered\non unhandled exceptions, fatal errors and user signals, in addition to\ntriggering programmatically through API calls.</p>\n<p>A complete example report that was generated on an uncaught exception\nis provided below for reference.</p>\n<pre><code class=\"language-json\">{\n \"header\": {\n \"reportVersion\": 1,\n \"event\": \"exception\",\n \"trigger\": \"Exception\",\n \"filename\": \"report.20181221.005011.8974.0.001.json\",\n \"dumpEventTime\": \"2018-12-21T00:50:11Z\",\n \"dumpEventTimeStamp\": \"1545371411331\",\n \"processId\": 8974,\n \"cwd\": \"/home/nodeuser/project/node\",\n \"commandLine\": [\n \"/home/nodeuser/project/node/out/Release/node\",\n \"--report-uncaught-exception\",\n \"/home/nodeuser/project/node/test/report/test-exception.js\",\n \"child\"\n ],\n \"nodejsVersion\": \"v12.0.0-pre\",\n \"glibcVersionRuntime\": \"2.17\",\n \"glibcVersionCompiler\": \"2.17\",\n \"wordSize\": \"64 bit\",\n \"arch\": \"x64\",\n \"platform\": \"linux\",\n \"componentVersions\": {\n \"node\": \"12.0.0-pre\",\n \"v8\": \"7.1.302.28-node.5\",\n \"uv\": \"1.24.1\",\n \"zlib\": \"1.2.11\",\n \"ares\": \"1.15.0\",\n \"modules\": \"68\",\n \"nghttp2\": \"1.34.0\",\n \"napi\": \"3\",\n \"llhttp\": \"1.0.1\",\n \"openssl\": \"1.1.0j\"\n },\n \"release\": {\n \"name\": \"node\"\n },\n \"osName\": \"Linux\",\n \"osRelease\": \"3.10.0-862.el7.x86_64\",\n \"osVersion\": \"#1 SMP Wed Mar 21 18:14:51 EDT 2018\",\n \"osMachine\": \"x86_64\",\n \"cpus\": [\n {\n \"model\": \"Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz\",\n \"speed\": 2700,\n \"user\": 88902660,\n \"nice\": 0,\n \"sys\": 50902570,\n \"idle\": 241732220,\n \"irq\": 0\n },\n {\n \"model\": \"Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz\",\n \"speed\": 2700,\n \"user\": 88902660,\n \"nice\": 0,\n \"sys\": 50902570,\n \"idle\": 241732220,\n \"irq\": 0\n }\n ],\n \"networkInterfaces\": [\n {\n \"name\": \"en0\",\n \"internal\": false,\n \"mac\": \"13:10:de:ad:be:ef\",\n \"address\": \"10.0.0.37\",\n \"netmask\": \"255.255.255.0\",\n \"family\": \"IPv4\"\n }\n ],\n \"host\": \"test_machine\"\n },\n \"javascriptStack\": {\n \"message\": \"Error: *** test-exception.js: throwing uncaught Error\",\n \"stack\": [\n \"at myException (/home/nodeuser/project/node/test/report/test-exception.js:9:11)\",\n \"at Object.&#x3C;anonymous> (/home/nodeuser/project/node/test/report/test-exception.js:12:3)\",\n \"at Module._compile (internal/modules/cjs/loader.js:718:30)\",\n \"at Object.Module._extensions..js (internal/modules/cjs/loader.js:729:10)\",\n \"at Module.load (internal/modules/cjs/loader.js:617:32)\",\n \"at tryModuleLoad (internal/modules/cjs/loader.js:560:12)\",\n \"at Function.Module._load (internal/modules/cjs/loader.js:552:3)\",\n \"at Function.Module.runMain (internal/modules/cjs/loader.js:771:12)\",\n \"at executeUserCode (internal/bootstrap/node.js:332:15)\"\n ]\n },\n \"nativeStack\": [\n {\n \"pc\": \"0x000055b57f07a9ef\",\n \"symbol\": \"report::GetNodeReport(v8::Isolate*, node::Environment*, char const*, char const*, v8::Local&#x3C;v8::String>, std::ostream&#x26;) [./node]\"\n },\n {\n \"pc\": \"0x000055b57f07cf03\",\n \"symbol\": \"report::GetReport(v8::FunctionCallbackInfo&#x3C;v8::Value> const&#x26;) [./node]\"\n },\n {\n \"pc\": \"0x000055b57f1bccfd\",\n \"symbol\": \" [./node]\"\n },\n {\n \"pc\": \"0x000055b57f1be048\",\n \"symbol\": \"v8::internal::Builtin_HandleApiCall(int, v8::internal::Object**, v8::internal::Isolate*) [./node]\"\n },\n {\n \"pc\": \"0x000055b57feeda0e\",\n \"symbol\": \" [./node]\"\n }\n ],\n \"javascriptHeap\": {\n \"totalMemory\": 5660672,\n \"executableMemory\": 524288,\n \"totalCommittedMemory\": 5488640,\n \"availableMemory\": 4341379928,\n \"totalGlobalHandlesMemory\": 8192,\n \"usedGlobalHandlesMemory\": 3136,\n \"usedMemory\": 4816432,\n \"memoryLimit\": 4345298944,\n \"mallocedMemory\": 254128,\n \"externalMemory\": 315644,\n \"peakMallocedMemory\": 98752,\n \"nativeContextCount\": 1,\n \"detachedContextCount\": 0,\n \"doesZapGarbage\": 0,\n \"heapSpaces\": {\n \"read_only_space\": {\n \"memorySize\": 524288,\n \"committedMemory\": 39208,\n \"capacity\": 515584,\n \"used\": 30504,\n \"available\": 485080\n },\n \"new_space\": {\n \"memorySize\": 2097152,\n \"committedMemory\": 2019312,\n \"capacity\": 1031168,\n \"used\": 985496,\n \"available\": 45672\n },\n \"old_space\": {\n \"memorySize\": 2273280,\n \"committedMemory\": 1769008,\n \"capacity\": 1974640,\n \"used\": 1725488,\n \"available\": 249152\n },\n \"code_space\": {\n \"memorySize\": 696320,\n \"committedMemory\": 184896,\n \"capacity\": 152128,\n \"used\": 152128,\n \"available\": 0\n },\n \"map_space\": {\n \"memorySize\": 536576,\n \"committedMemory\": 344928,\n \"capacity\": 327520,\n \"used\": 327520,\n \"available\": 0\n },\n \"large_object_space\": {\n \"memorySize\": 0,\n \"committedMemory\": 0,\n \"capacity\": 1520590336,\n \"used\": 0,\n \"available\": 1520590336\n },\n \"new_large_object_space\": {\n \"memorySize\": 0,\n \"committedMemory\": 0,\n \"capacity\": 0,\n \"used\": 0,\n \"available\": 0\n }\n }\n },\n \"resourceUsage\": {\n \"userCpuSeconds\": 0.069595,\n \"kernelCpuSeconds\": 0.019163,\n \"cpuConsumptionPercent\": 0.000000,\n \"maxRss\": 18079744,\n \"pageFaults\": {\n \"IORequired\": 0,\n \"IONotRequired\": 4610\n },\n \"fsActivity\": {\n \"reads\": 0,\n \"writes\": 0\n }\n },\n \"uvthreadResourceUsage\": {\n \"userCpuSeconds\": 0.068457,\n \"kernelCpuSeconds\": 0.019127,\n \"cpuConsumptionPercent\": 0.000000,\n \"fsActivity\": {\n \"reads\": 0,\n \"writes\": 0\n }\n },\n \"libuv\": [\n {\n \"type\": \"async\",\n \"is_active\": true,\n \"is_referenced\": false,\n \"address\": \"0x0000000102910900\",\n \"details\": \"\"\n },\n {\n \"type\": \"timer\",\n \"is_active\": false,\n \"is_referenced\": false,\n \"address\": \"0x00007fff5fbfeab0\",\n \"repeat\": 0,\n \"firesInMsFromNow\": 94403548320796,\n \"expired\": true\n },\n {\n \"type\": \"check\",\n \"is_active\": true,\n \"is_referenced\": false,\n \"address\": \"0x00007fff5fbfeb48\"\n },\n {\n \"type\": \"idle\",\n \"is_active\": false,\n \"is_referenced\": true,\n \"address\": \"0x00007fff5fbfebc0\"\n },\n {\n \"type\": \"prepare\",\n \"is_active\": false,\n \"is_referenced\": false,\n \"address\": \"0x00007fff5fbfec38\"\n },\n {\n \"type\": \"check\",\n \"is_active\": false,\n \"is_referenced\": false,\n \"address\": \"0x00007fff5fbfecb0\"\n },\n {\n \"type\": \"async\",\n \"is_active\": true,\n \"is_referenced\": false,\n \"address\": \"0x000000010188f2e0\"\n },\n {\n \"type\": \"tty\",\n \"is_active\": false,\n \"is_referenced\": true,\n \"address\": \"0x000055b581db0e18\",\n \"width\": 204,\n \"height\": 55,\n \"fd\": 17,\n \"writeQueueSize\": 0,\n \"readable\": true,\n \"writable\": true\n },\n {\n \"type\": \"signal\",\n \"is_active\": true,\n \"is_referenced\": false,\n \"address\": \"0x000055b581d80010\",\n \"signum\": 28,\n \"signal\": \"SIGWINCH\"\n },\n {\n \"type\": \"tty\",\n \"is_active\": true,\n \"is_referenced\": true,\n \"address\": \"0x000055b581df59f8\",\n \"width\": 204,\n \"height\": 55,\n \"fd\": 19,\n \"writeQueueSize\": 0,\n \"readable\": true,\n \"writable\": true\n },\n {\n \"type\": \"loop\",\n \"is_active\": true,\n \"address\": \"0x000055fc7b2cb180\",\n \"loopIdleTimeSeconds\": 22644.8\n }\n ],\n \"workers\": [],\n \"environmentVariables\": {\n \"REMOTEHOST\": \"REMOVED\",\n \"MANPATH\": \"/opt/rh/devtoolset-3/root/usr/share/man:\",\n \"XDG_SESSION_ID\": \"66126\",\n \"HOSTNAME\": \"test_machine\",\n \"HOST\": \"test_machine\",\n \"TERM\": \"xterm-256color\",\n \"SHELL\": \"/bin/csh\",\n \"SSH_CLIENT\": \"REMOVED\",\n \"PERL5LIB\": \"/opt/rh/devtoolset-3/root//usr/lib64/perl5/vendor_perl:/opt/rh/devtoolset-3/root/usr/lib/perl5:/opt/rh/devtoolset-3/root//usr/share/perl5/vendor_perl\",\n \"OLDPWD\": \"/home/nodeuser/project/node/src\",\n \"JAVACONFDIRS\": \"/opt/rh/devtoolset-3/root/etc/java:/etc/java\",\n \"SSH_TTY\": \"/dev/pts/0\",\n \"PCP_DIR\": \"/opt/rh/devtoolset-3/root\",\n \"GROUP\": \"normaluser\",\n \"USER\": \"nodeuser\",\n \"LD_LIBRARY_PATH\": \"/opt/rh/devtoolset-3/root/usr/lib64:/opt/rh/devtoolset-3/root/usr/lib\",\n \"HOSTTYPE\": \"x86_64-linux\",\n \"XDG_CONFIG_DIRS\": \"/opt/rh/devtoolset-3/root/etc/xdg:/etc/xdg\",\n \"MAIL\": \"/var/spool/mail/nodeuser\",\n \"PATH\": \"/home/nodeuser/project/node:/opt/rh/devtoolset-3/root/usr/bin:/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin\",\n \"PWD\": \"/home/nodeuser/project/node\",\n \"LANG\": \"en_US.UTF-8\",\n \"PS1\": \"\\\\u@\\\\h : \\\\[\\\\e[31m\\\\]\\\\w\\\\[\\\\e[m\\\\] > \",\n \"SHLVL\": \"2\",\n \"HOME\": \"/home/nodeuser\",\n \"OSTYPE\": \"linux\",\n \"VENDOR\": \"unknown\",\n \"PYTHONPATH\": \"/opt/rh/devtoolset-3/root/usr/lib64/python2.7/site-packages:/opt/rh/devtoolset-3/root/usr/lib/python2.7/site-packages\",\n \"MACHTYPE\": \"x86_64\",\n \"LOGNAME\": \"nodeuser\",\n \"XDG_DATA_DIRS\": \"/opt/rh/devtoolset-3/root/usr/share:/usr/local/share:/usr/share\",\n \"LESSOPEN\": \"||/usr/bin/lesspipe.sh %s\",\n \"INFOPATH\": \"/opt/rh/devtoolset-3/root/usr/share/info\",\n \"XDG_RUNTIME_DIR\": \"/run/user/50141\",\n \"_\": \"./node\"\n },\n \"userLimits\": {\n \"core_file_size_blocks\": {\n \"soft\": \"\",\n \"hard\": \"unlimited\"\n },\n \"data_seg_size_kbytes\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n },\n \"file_size_blocks\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n },\n \"max_locked_memory_bytes\": {\n \"soft\": \"unlimited\",\n \"hard\": 65536\n },\n \"max_memory_size_kbytes\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n },\n \"open_files\": {\n \"soft\": \"unlimited\",\n \"hard\": 4096\n },\n \"stack_size_bytes\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n },\n \"cpu_time_seconds\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n },\n \"max_user_processes\": {\n \"soft\": \"unlimited\",\n \"hard\": 4127290\n },\n \"virtual_memory_kbytes\": {\n \"soft\": \"unlimited\",\n \"hard\": \"unlimited\"\n }\n },\n \"sharedObjects\": [\n \"/lib64/libdl.so.2\",\n \"/lib64/librt.so.1\",\n \"/lib64/libstdc++.so.6\",\n \"/lib64/libm.so.6\",\n \"/lib64/libgcc_s.so.1\",\n \"/lib64/libpthread.so.0\",\n \"/lib64/libc.so.6\",\n \"/lib64/ld-linux-x86-64.so.2\"\n ]\n}\n</code></pre>", "miscs": [ { "textRaw": "Usage", "name": "usage", "desc": "<pre><code class=\"language-bash\">node --report-uncaught-exception --report-on-signal \\\n--report-on-fatalerror app.js\n</code></pre>\n<ul>\n<li>\n<p><code>--report-uncaught-exception</code> Enables report to be generated on\nun-caught exceptions. Useful when inspecting JavaScript stack in conjunction\nwith native stack and other runtime environment data.</p>\n</li>\n<li>\n<p><code>--report-on-signal</code> Enables report to be generated upon receiving\nthe specified (or predefined) signal to the running Node.js process. (See\nbelow on how to modify the signal that triggers the report.) Default signal is\n<code>SIGUSR2</code>. Useful when a report needs to be triggered from another program.\nApplication monitors may leverage this feature to collect report at regular\nintervals and plot rich set of internal runtime data to their views.</p>\n</li>\n</ul>\n<p>Signal based report generation is not supported in Windows.</p>\n<p>Under normal circumstances, there is no need to modify the report triggering\nsignal. However, if <code>SIGUSR2</code> is already used for other purposes, then this\nflag helps to change the signal for report generation and preserve the original\nmeaning of <code>SIGUSR2</code> for the said purposes.</p>\n<ul>\n<li>\n<p><code>--report-on-fatalerror</code> Enables the report to be triggered on fatal errors\n(internal errors within the Node.js runtime, such as out of memory)\nthat leads to termination of the application. Useful to inspect various\ndiagnostic data elements such as heap, stack, event loop state, resource\nconsumption etc. to reason about the fatal error.</p>\n</li>\n<li>\n<p><code>--report-compact</code> Write reports in a compact format, single-line JSON, more\neasily consumable by log processing systems than the default multi-line format\ndesigned for human consumption.</p>\n</li>\n<li>\n<p><code>--report-directory</code> Location at which the report will be\ngenerated.</p>\n</li>\n<li>\n<p><code>--report-filename</code> Name of the file to which the report will be\nwritten.</p>\n</li>\n<li>\n<p><code>--report-signal</code> Sets or resets the signal for report generation\n(not supported on Windows). Default signal is <code>SIGUSR2</code>.</p>\n</li>\n</ul>\n<p>A report can also be triggered via an API call from a JavaScript application:</p>\n<pre><code class=\"language-js\">process.report.writeReport();\n</code></pre>\n<p>This function takes an optional additional argument <code>filename</code>, which is\nthe name of a file into which the report is written.</p>\n<pre><code class=\"language-js\">process.report.writeReport('./foo.json');\n</code></pre>\n<p>This function takes an optional additional argument <code>err</code> which is an <code>Error</code>\nobject that will be used as the context for the JavaScript stack printed in the\nreport. When using report to handle errors in a callback or an exception\nhandler, this allows the report to include the location of the original error as\nwell as where it was handled.</p>\n<pre><code class=\"language-js\">try {\n process.chdir('/non-existent-path');\n} catch (err) {\n process.report.writeReport(err);\n}\n// Any other code\n</code></pre>\n<p>If both filename and error object are passed to <code>writeReport()</code> the\nerror object must be the second parameter.</p>\n<pre><code class=\"language-js\">try {\n process.chdir('/non-existent-path');\n} catch (err) {\n process.report.writeReport(filename, err);\n}\n// Any other code\n</code></pre>\n<p>The content of the diagnostic report can be returned as a JavaScript Object\nvia an API call from a JavaScript application:</p>\n<pre><code class=\"language-js\">const report = process.report.getReport();\nconsole.log(typeof report === 'object'); // true\n\n// Similar to process.report.writeReport() output\nconsole.log(JSON.stringify(report, null, 2));\n</code></pre>\n<p>This function takes an optional additional argument <code>err</code>, which is an <code>Error</code>\nobject that will be used as the context for the JavaScript stack printed in the\nreport.</p>\n<pre><code class=\"language-js\">const report = process.report.getReport(new Error('custom error'));\nconsole.log(typeof report === 'object'); // true\n</code></pre>\n<p>The API versions are useful when inspecting the runtime state from within\nthe application, in expectation of self-adjusting the resource consumption,\nload balancing, monitoring etc.</p>\n<p>The content of the report consists of a header section containing the event\ntype, date, time, PID, and Node.js version, sections containing JavaScript and\nnative stack traces, a section containing V8 heap information, a section\ncontaining <code>libuv</code> handle information, and an OS platform information section\nshowing CPU and memory usage and system limits. An example report can be\ntriggered using the Node.js REPL:</p>\n<pre><code class=\"language-console\">$ node\n> process.report.writeReport();\nWriting Node.js report to file: report.20181126.091102.8480.0.001.json\nNode.js report completed\n>\n</code></pre>\n<p>When a report is written, start and end messages are issued to stderr\nand the filename of the report is returned to the caller. The default filename\nincludes the date, time, PID, and a sequence number. The sequence number helps\nin associating the report dump with the runtime state if generated multiple\ntimes for the same Node.js process.</p>", "type": "misc", "displayName": "Usage" }, { "textRaw": "Configuration", "name": "configuration", "desc": "<p>Additional runtime configuration of report generation is available via\nthe following properties of <code>process.report</code>:</p>\n<p><code>reportOnFatalError</code> triggers diagnostic reporting on fatal errors when <code>true</code>.\nDefaults to <code>false</code>.</p>\n<p><code>reportOnSignal</code> triggers diagnostic reporting on signal when <code>true</code>. This is\nnot supported on Windows. Defaults to <code>false</code>.</p>\n<p><code>reportOnUncaughtException</code> triggers diagnostic reporting on uncaught exception\nwhen <code>true</code>. Defaults to <code>false</code>.</p>\n<p><code>signal</code> specifies the POSIX signal identifier that will be used\nto intercept external triggers for report generation. Defaults to\n<code>'SIGUSR2'</code>.</p>\n<p><code>filename</code> specifies the name of the output file in the file system.\nSpecial meaning is attached to <code>stdout</code> and <code>stderr</code>. Usage of these\nwill result in report being written to the associated standard streams.\nIn cases where standard streams are used, the value in <code>directory</code> is ignored.\nURLs are not supported. Defaults to a composite filename that contains\ntimestamp, PID, and sequence number.</p>\n<p><code>directory</code> specifies the filesystem directory where the report will be written.\nURLs are not supported. Defaults to the current working directory of the\nNode.js process.</p>\n<pre><code class=\"language-js\">// Trigger report only on uncaught exceptions.\nprocess.report.reportOnFatalError = false;\nprocess.report.reportOnSignal = false;\nprocess.report.reportOnUncaughtException = true;\n\n// Trigger report for both internal errors as well as external signal.\nprocess.report.reportOnFatalError = true;\nprocess.report.reportOnSignal = true;\nprocess.report.reportOnUncaughtException = false;\n\n// Change the default signal to 'SIGQUIT' and enable it.\nprocess.report.reportOnFatalError = false;\nprocess.report.reportOnUncaughtException = false;\nprocess.report.reportOnSignal = true;\nprocess.report.signal = 'SIGQUIT';\n</code></pre>\n<p>Configuration on module initialization is also available via\nenvironment variables:</p>\n<pre><code class=\"language-bash\">NODE_OPTIONS=\"--report-uncaught-exception \\\n --report-on-fatalerror --report-on-signal \\\n --report-signal=SIGUSR2 --report-filename=./report.json \\\n --report-directory=/home/nodeuser\"\n</code></pre>\n<p>Specific API documentation can be found under\n<a href=\"process.html\"><code>process API documentation</code></a> section.</p>", "type": "misc", "displayName": "Configuration" }, { "textRaw": "Interaction with workers", "name": "interaction_with_workers", "meta": { "changes": [ { "version": [ "v13.9.0", "v12.16.2" ], "pr-url": "https://github.com/nodejs/node/pull/31386", "description": "Workers are now included in the report." } ] }, "desc": "<p><a href=\"worker_threads.html\"><code>Worker</code></a> threads can create reports in the same way that the main thread\ndoes.</p>\n<p>Reports will include information on any Workers that are children of the current\nthread as part of the <code>workers</code> section, with each Worker generating a report\nin the standard report format.</p>\n<p>The thread which is generating the report will wait for the reports from Worker\nthreads to finish. However, the latency for this will usually be low, as both\nrunning JavaScript and the event loop are interrupted to generate the report.</p>", "type": "misc", "displayName": "Interaction with workers" } ] } ] }