feat: use data Error for callStack information

Zachary Haber · Zachary Haber · commit e7ea4039ab54 · 2022-06-17T14:31:54.000-05:00
use the first data value if an Error to get callstack info. Only 1 line will be stripped from it by default Refs: #1268
diff --git a/lib/logger.js b/lib/logger.js
@@ -1,17 +1,39 @@
 /* eslint no-underscore-dangle: ["error", { "allow": ["_log"] }] */
 
-const debug = require("debug")("log4js:logger");
-const LoggingEvent = require("./LoggingEvent");
-const levels = require("./levels");
-const clustering = require("./clustering");
-const categories = require("./categories");
-const configuration = require("./configuration");
+const debug = require('debug')('log4js:logger');
+const LoggingEvent = require('./LoggingEvent');
+const levels = require('./levels');
+const clustering = require('./clustering');
+const categories = require('./categories');
+const configuration = require('./configuration');
 
 const stackReg = /at (?:(.+)\s+\()?(?:(.+?):(\d+)(?::(\d+))?|([^)]+))\)?/;
+/**
+ * The top entry is the Error
+ */
+const baseCallStackSkip = 1;
+/**
+ * The _log function is 3 levels deep, we need to skip those to make it to the callSite
+ */
+const defaultErrorCallStackSkip = 3;
 
-function defaultParseCallStack(data, skipIdx = 4) {
+/**
+ *
+ * @param {Error} data
+ * @param {number} skipIdx
+ * @returns {import('../types/log4js').CallStack | null}
+ */
+function defaultParseCallStack(
+  data,
+  skipIdx = defaultErrorCallStackSkip + baseCallStackSkip
+) {
   try {
-    const stacklines = data.stack.split("\n").slice(skipIdx);
+    const stacklines = data.stack.split('\n').slice(skipIdx);
+    if (!stacklines.length) {
+      // There's no stack in this stack
+      // Should we try a previous index if skipIdx was set?
+      return null;
+    }
     const lineMatch = stackReg.exec(stacklines[0]);
     /* istanbul ignore else: failsafe */
     if (lineMatch && lineMatch.length === 6) {
@@ -20,14 +42,14 @@ function defaultParseCallStack(data, skipIdx = 4) {
         fileName: lineMatch[2],
         lineNumber: parseInt(lineMatch[3], 10),
         columnNumber: parseInt(lineMatch[4], 10),
-        callStack: stacklines.join("\n")
+        callStack: stacklines.join('\n'),
       };
-    } else { // eslint-disable-line no-else-return
+      // eslint-disable-next-line no-else-return
+    } else {
       // will never get here unless nodejs has changes to Error
       console.error('log4js.logger - defaultParseCallStack error'); // eslint-disable-line no-console
     }
-  }
-  catch (err) {
+  } catch (err) {
     // will never get error unless nodejs has breaking changes to Error
     console.error('log4js.logger - defaultParseCallStack error', err); // eslint-disable-line no-console
   }
@@ -49,10 +71,11 @@ function defaultParseCallStack(data, skipIdx = 4) {
 class Logger {
   constructor(name) {
     if (!name) {
-      throw new Error("No category provided.");
+      throw new Error('No category provided.');
     }
     this.category = name;
     this.context = {};
+    /** @private */
     this.parseCallStack = defaultParseCallStack;
     debug(`Logger created (${this.category}, ${this.level})`);
   }
@@ -84,7 +107,11 @@ class Logger {
     if (!logLevel) {
       if (configuration.validIdentifier(level) && args.length > 0) {
         // logLevel not found but of valid signature, WARN before fallback to INFO
-        this.log(levels.WARN, 'log4js:logger.log: valid log-level not found as first parameter given:', level);
+        this.log(
+          levels.WARN,
+          'log4js:logger.log: valid log-level not found as first parameter given:',
+          level
+        );
         this.log(levels.INFO, `[${level}]`, ...args);
       } else {
         // apart from fallback, allow .log(...args) to be synonym with .log("INFO", ...args)
@@ -101,12 +128,28 @@ class Logger {
 
   _log(level, data) {
     debug(`sending log data (${level}) to appenders`);
+    let callStack;
+    if (this.useCallStack) {
+      try {
+        if (data[0] instanceof Error) {
+          callStack = this.parseCallStack(data[0], baseCallStackSkip);
+        }
+      } catch (_err) {
+        // Ignore Error
+      }
+      callStack =
+        callStack ||
+        this.parseCallStack(
+          new Error(),
+          defaultErrorCallStackSkip + baseCallStackSkip
+        );
+    }
     const loggingEvent = new LoggingEvent(
       this.category,
       level,
       data,
       this.context,
-      this.useCallStack && this.parseCallStack(new Error())
+      callStack
     );
     clustering.send(loggingEvent);
   }
@@ -132,7 +175,7 @@ function addLevelMethods(target) {
   const level = levels.getLevel(target);
 
   const levelStrLower = level.toString().toLowerCase();
-  const levelMethod = levelStrLower.replace(/_([a-z])/g, g =>
+  const levelMethod = levelStrLower.replace(/_([a-z])/g, (g) =>
     g[1].toUpperCase()
   );
   const isLevelMethod = levelMethod[0].toUpperCase() + levelMethod.slice(1);
