Add handleRejections support (winstonjs#1462)

* Add handleRejections suppot

* Correct typo

Author: drazisil

lib/winston.js

@@ -51,6 +51,11 @@ winston.createLogger = require('./winston/create-logger');
  * @type {Object}
  */
 winston.ExceptionHandler = require('./winston/exception-handler');
+/**
+ * Expose core Logging-related prototypes.
+ * @type {Object}
+ */
+winston.RejectionHandler = require('./winston/rejection-handler');
 /**
  * Expose core Logging-related prototypes.
  * @type {Container}
@@ -85,21 +90,25 @@ winston.loggers = new winston.Container();
 const defaultLogger = winston.createLogger();
 
 // Pass through the target methods onto `winston.
-Object.keys(winston.config.npm.levels).concat([
-  'log',
-  'query',
-  'stream',
-  'add',
-  'remove',
-  'clear',
-  'profile',
-  'startTimer',
-  'handleExceptions',
-  'unhandleExceptions',
-  'configure'
-]).forEach(method => (
-  winston[method] = (...args) => defaultLogger[method](...args)
-));
+Object.keys(winston.config.npm.levels)
+  .concat([
+    'log',
+    'query',
+    'stream',
+    'add',
+    'remove',
+    'clear',
+    'profile',
+    'startTimer',
+    'handleExceptions',
+    'unhandleExceptions',
+    'handleRejections',
+    'unhandleRejections',
+    'configure'
+  ])
+  .forEach(
+    method => (winston[method] = (...args) => defaultLogger[method](...args))
+  );
 
 /**
  * Define getter / setter for the default logger level which need to be exposed
@@ -131,9 +140,7 @@ Object.defineProperty(winston, 'exceptions', {
  * which need to be exposed by winston.
  * @type {Logger}
  */
-[
-  'exitOnError'
-].forEach(prop => {
+['exitOnError'].forEach(prop => {
   Object.defineProperty(winston, prop, {
     get() {
       return defaultLogger[prop];
@@ -152,6 +159,7 @@ Object.defineProperty(winston, 'default', {
   get() {
     return {
       exceptionHandlers: defaultLogger.exceptionHandlers,
+      rejectionHandlers: defaultLogger.rejectionHandlers,
       transports: defaultLogger.transports
     };
   }
@@ -160,20 +168,14 @@ Object.defineProperty(winston, 'default', {
 // Have friendlier breakage notices for properties that were exposed by default
 // on winston < 3.0.
 warn.deprecated(winston, 'setLevels');
-warn.forFunctions(winston,  'useFormat',  ['cli']);
-warn.forProperties(winston, 'useFormat',  [
-  'padLevels',
-  'stripColors'
-]);
-warn.forFunctions(winston,  'deprecated', [
+warn.forFunctions(winston, 'useFormat', ['cli']);
+warn.forProperties(winston, 'useFormat', ['padLevels', 'stripColors']);
+warn.forFunctions(winston, 'deprecated', [
   'addRewriter',
   'addFilter',
   'clone',
   'extend'
 ]);
-warn.forProperties(winston, 'deprecated', [
-  'emitErrs',
-  'levelLength'
-]);
+warn.forProperties(winston, 'deprecated', ['emitErrs', 'levelLength']);
 // Throw a useful error when users attempt to run `new winston.Logger`.
 warn.moved(winston, 'createLogger', 'Logger');

lib/winston/logger.js

@@ -12,6 +12,7 @@ const asyncForEach = require('async/forEach');
 const { LEVEL, SPLAT } = require('triple-beam');
 const isStream = require('is-stream');
 const ExceptionHandler = require('./exception-handler');
+const RejectionHandler = require('./rejection-handler');
 const LegacyTransportStream = require('winston-transport/legacy');
 const Profiler = require('./profiler');
 const { warn } = require('./common');
@@ -88,7 +89,8 @@ class Logger extends Transform {
     padLevels,
     rewriters,
     stripColors,
-    exceptionHandlers
+    exceptionHandlers,
+    rejectionHandlers
   } = {}) {
     // Reset transports if we already have them
     if (this.transports.length) {
@@ -103,6 +105,7 @@ class Logger extends Transform {
     this.levels = levels || this.levels || config.npm.levels;
     this.level = level;
     this.exceptions = new ExceptionHandler(this);
+    this.rejections = new RejectionHandler(this);
     this.profilers = {};
     this.exitOnError = exitOnError;
 
@@ -113,19 +116,28 @@ class Logger extends Transform {
     }
 
     if (
-      colors || emitErrs || formatters ||
-      padLevels || rewriters || stripColors
+      colors ||
+      emitErrs ||
+      formatters ||
+      padLevels ||
+      rewriters ||
+      stripColors
     ) {
-      throw new Error([
-        '{ colors, emitErrs, formatters, padLevels, rewriters, stripColors } were removed in [email protected].',
-        'Use a custom winston.format(function) instead.',
-        'See: https://github.com/winstonjs/winston/tree/master/UPGRADE-3.0.md'
-      ].join('\n'));
+      throw new Error(
+        [
+          '{ colors, emitErrs, formatters, padLevels, rewriters, stripColors } were removed in [email protected].',
+          'Use a custom winston.format(function) instead.',
+          'See: https://github.com/winstonjs/winston/tree/master/UPGRADE-3.0.md'
+        ].join('\n')
+      );
     }
 
     if (exceptionHandlers) {
       this.exceptions.handle(exceptionHandlers);
     }
+    if (rejectionHandlers) {
+      this.rejections.handle(rejectionHandlers);
+    }
   }
 
   isLevelEnabled(level) {
@@ -183,7 +195,8 @@ class Logger extends Transform {
    *
    */
   /* eslint-enable valid-jsdoc */
-  log(level, msg, ...splat) { // eslint-disable-line max-params
+  log(level, msg, ...splat) {
+    // eslint-disable-line max-params
     // Optimize for the hotpath of logging JSON literals
     if (arguments.length === 1) {
       // Yo dawg, I heard you like levels ... seriously ...
@@ -276,7 +289,10 @@ class Logger extends Transform {
     // Remark: not sure if we should simply error here.
     if (!this._readableState.pipes) {
       // eslint-disable-next-line no-console
-      console.error('[winston] Attempt to write logs with no transports %j', info);
+      console.error(
+        '[winston] Attempt to write logs with no transports %j',
+        info
+      );
     }
 
     // Here we write to the `format` pipe-chain, which on `readable` above will
@@ -300,11 +316,15 @@ class Logger extends Transform {
    */
   _final(callback) {
     const transports = this.transports.slice();
-    asyncForEach(transports, (transport, next) => {
-      if (!transport || transport.finished) return setImmediate(next);
-      transport.once('finish', next);
-      transport.end();
-    }, callback);
+    asyncForEach(
+      transports,
+      (transport, next) => {
+        if (!transport || transport.finished) return setImmediate(next);
+        transport.once('finish', next);
+        transport.end();
+      },
+      callback
+    );
   }
 
   /**
@@ -318,12 +338,15 @@ class Logger extends Transform {
     // 1. They inherit from winston.Transport in  < 3.x.x which is NOT a stream.
     // 2. They expose a log method which has a length greater than 2 (i.e. more then
     //    just `log(info, callback)`.
-    const target = !isStream(transport) || transport.log.length > 2
-      ? new LegacyTransportStream({ transport })
-      : transport;
+    const target =
+      !isStream(transport) || transport.log.length > 2
+        ? new LegacyTransportStream({ transport })
+        : transport;
 
     if (!target._writableState || !target._writableState.objectMode) {
-      throw new Error('Transports must WritableStreams in objectMode. Set { objectMode: true }.');
+      throw new Error(
+        'Transports must WritableStreams in objectMode. Set { objectMode: true }.'
+      );
     }
 
     // Listen for the `error` event and the `warn` event on the new Transport.
@@ -335,6 +358,10 @@ class Logger extends Transform {
       this.exceptions.handle();
     }
 
+    if (transport.handleRejections) {
+      this.rejections.handle();
+    }
+
     return this;
   }
 
@@ -346,11 +373,14 @@ class Logger extends Transform {
   remove(transport) {
     let target = transport;
     if (!isStream(transport) || transport.log.length > 2) {
-      target = this.transports
-        .filter(match => match.transport === transport)[0];
+      target = this.transports.filter(
+        match => match.transport === transport
+      )[0];
     }
 
-    if (target) { this.unpipe(target); }
+    if (target) {
+      this.unpipe(target);
+    }
     return this;
   }
 
@@ -523,7 +553,9 @@ class Logger extends Transform {
       // Attempt to be kind to users if they are still using older APIs.
       if (typeof args[args.length - 2] === 'function') {
         // eslint-disable-next-line no-console
-        console.warn('Callback function no longer supported as of [email protected]');
+        console.warn(
+          'Callback function no longer supported as of [email protected]'
+        );
         args.pop();
       }
 
@@ -546,7 +578,9 @@ class Logger extends Transform {
    */
   handleExceptions(...args) {
     // eslint-disable-next-line no-console
-    console.warn('Deprecated: .handleExceptions() will be removed in winston@4. Use .exceptions.handle()');
+    console.warn(
+      'Deprecated: .handleExceptions() will be removed in winston@4. Use .exceptions.handle()'
+    );
     this.exceptions.handle(...args);
   }
 
@@ -557,7 +591,9 @@ class Logger extends Transform {
    */
   unhandleExceptions(...args) {
     // eslint-disable-next-line no-console
-    console.warn('Deprecated: .unhandleExceptions() will be removed in winston@4. Use .exceptions.unhandle()');
+    console.warn(
+      'Deprecated: .unhandleExceptions() will be removed in winston@4. Use .exceptions.unhandle()'
+    );
     this.exceptions.unhandle(...args);
   }
 
@@ -566,11 +602,13 @@ class Logger extends Transform {
    * @throws {Error} - TODO: add throws description.
    */
   cli() {
-    throw new Error([
-      'Logger.cli() was removed in [email protected]',
-      'Use a custom winston.formats.cli() instead.',
-      'See: https://github.com/winstonjs/winston/tree/master/UPGRADE-3.0.md'
-    ].join('\n'));
+    throw new Error(
+      [
+        'Logger.cli() was removed in [email protected]',
+        'Use a custom winston.formats.cli() instead.',
+        'See: https://github.com/winstonjs/winston/tree/master/UPGRADE-3.0.md'
+      ].join('\n')
+    );
   }
 
   /**