Work towards 4.0

examples/using-winston-transport.js

@@ -0,0 +1,27 @@
+var winston = require('winston'),
+    WinstonCloudWatch = require('../index');
+
+function format(message, ...rest) {
+  // I am inventing a custom formatter
+  return `
+    ${message}
+    ${rest.map(r => ` * ${r}`).join('\n')}
+  `
+}
+
+function customFormatter({level, message, [Symbol.for('splat')]: args = []}) {
+  return `${level} - ${format(message, ...args)}`;
+}
+
+var transport = winston.createLogger({
+  exitOnError: false,
+  transports: [
+    new WinstonCloudWatch({
+      logGroupName: 'testing',
+      logStreamName: 'first',
+      awsRegion: 'us-east-1',
+    })],
+  format: winston.format.printf(customFormatter)
+});
+
+transport.info('some text', {foo: 'bar'}, new Error('wtf'));

index.js

@@ -1,150 +1,146 @@
-'use strict';
-
-var util = require('util'),
-    winston = require('winston'),
-    AWS = require('aws-sdk'),
-    cloudWatchIntegration = require('./lib/cloudwatch-integration'),
-    isEmpty = require('lodash.isempty'),
-    assign = require('lodash.assign'),
-    isError = require('lodash.iserror'),
-    stringify = require('./lib/utils').stringify,
-    debug = require('./lib/utils').debug,
-    defaultFlushTimeoutMs = 10000;
-
-var WinstonCloudWatch = function(options) {
-  winston.Transport.call(this, options);
-  this.level = options.level || 'info';
-  this.name = options.name || 'CloudWatch';
-  this.logGroupName = options.logGroupName;
-  this.retentionInDays = options.retentionInDays || 0;
-  this.logStreamName = options.logStreamName;
-
-  var awsAccessKeyId = options.awsAccessKeyId;
-  var awsSecretKey = options.awsSecretKey;
-  var awsRegion = options.awsRegion;
-  var messageFormatter = options.messageFormatter ? options.messageFormatter : function(log) {
-    return [ log.level, log.message ].join(' - ')
-  };
-  this.formatMessage = options.jsonMessage ? stringify : messageFormatter;
-  this.proxyServer = options.proxyServer;
-  this.uploadRate = options.uploadRate || 2000;
-  this.logEvents = [];
-  this.errorHandler = options.errorHandler;
-
-  if (options.cloudWatchLogs) {
-    this.cloudwatchlogs = options.cloudWatchLogs;
-  } else {
-    if (this.proxyServer) {
-      AWS.config.update({
-        httpOptions: {
-          agent: require('proxy-agent')(this.proxyServer)
-        }
-      });
-    }
-
-    var config = {};
+const winston = require('winston'),
+      Transport = require('winston-transport'),
+      AWS = require('aws-sdk'),
+      { LEVEL, MESSAGE } = require('triple-beam'),
+      cloudWatchIntegration = require('./lib/cloudwatch-integration'),
+      isEmpty = require('lodash.isempty'),
+      assign = require('lodash.assign'),
+      isError = require('lodash.iserror'),
+      stringify = require('./lib/utils').stringify,
+      debug = require('./lib/utils').debug
+
+const defaultFlushTimeoutMs = 10000
+
+
+module.exports = class WinstonCloudwatch extends Transport {
+  constructor(opts) {
+    super(opts)
+    this.setOptions(opts)
+    debug('constructor finished')
+  }
 
-    if (awsAccessKeyId && awsSecretKey && awsRegion) {
-      config = { accessKeyId: awsAccessKeyId, secretAccessKey: awsSecretKey, region: awsRegion };
-    } else if (awsRegion && !awsAccessKeyId && !awsSecretKey) {
-      // Amazon SDK will automatically pull access credentials
-      // from IAM Role when running on EC2 but region still
-      // needs to be configured
-      config = { region: awsRegion };
+  log(info, callback) {
+    debug('log (called by winston)', info);
+    if (!isEmpty(info.message) || isError(info.message)) { 
+      this.add(info);
     }
 
-    if (options.awsOptions) {
-      config = assign(config, options.awsOptions);
+    if (!/^uncaughtException: /.test(info.message)) {
+      // do not wait, just return right away
+      return callback(null, true);
     }
 
-    this.cloudwatchlogs = new AWS.CloudWatchLogs(config);
-  }
+    debug('message not empty, proceeding')
 
-  debug('constructor finished');
-};
-
-util.inherits(WinstonCloudWatch, winston.Transport);
-
-WinstonCloudWatch.prototype.log = function (info, callback) {
-  debug('log (called by winston)', info);
-
-  if (!isEmpty(info.message) || isError(info.message)) { 
-    this.add(info);
+    // clear interval and send logs immediately
+    // as Winston is about to end the process
+    clearInterval(this.intervalId);
+    this.intervalId = null;
+    this.submit(callback);
   }
 
-  if (!/^uncaughtException: /.test(info.message)) {
-    // do not wait, just return right away
-    return callback(null, true);
-  }
+  add(log) {
+    debug('add log to queue', log);
 
-  debug('message not empty, proceeding')
+    if (!isEmpty(log.message) || isError(log.message)) {
+      this.logEvents.push({
+        message: this.formatMessage(log),
+        timestamp: new Date().getTime()
+      });
+    }
 
-  // clear interval and send logs immediately
-  // as Winston is about to end the process
-  clearInterval(this.intervalId);
-  this.intervalId = null;
-  this.submit(callback);
-};
+    if (!this.intervalId) {
+      debug('creating interval');
+      this.intervalId = setInterval(() => {
+        this.submit((err) => {
+          if (err) {
+            debug('error during submit', err, true);
+            this.errorHandler ? this.errorHandler(err) : console.error(err);
+          }
+        });
+      }, this.uploadRate);
+    }
+  }
 
-WinstonCloudWatch.prototype.add = function(log) {
-  debug('add log to queue', log);
+  submit(callback) {
+    var groupName = typeof this.logGroupName === 'function' ?
+        this.logGroupName() : this.logGroupName
+    var streamName = typeof this.logStreamName === 'function' ?
+        this.logStreamName() : this.logStreamName
+    var retentionInDays = this.retentionInDays
 
-  var self = this;
+    if (isEmpty(this.logEvents)) {
+      return callback()
+    }
 
-  if (!isEmpty(log.message) || isError(log.message)) {
-    self.logEvents.push({
-      message: self.formatMessage(log),
-      timestamp: new Date().getTime()
-    });
+    cloudWatchIntegration.upload(
+      this.cloudwatchlogs,
+      groupName,
+      streamName,
+      this.logEvents,
+      retentionInDays,
+      callback
+    )
   }
 
-  if (!self.intervalId) {
-    debug('creating interval');
-    self.intervalId = setInterval(function() {
-      self.submit(function(err) {
-        if (err) {
-          debug('error during submit', err, true);
-          self.errorHandler ? self.errorHandler(err) : console.error(err);
-        }
-      });
-    }, self.uploadRate);
+  kthxbye(callback) {
+    clearInterval(this.intervalId);
+    this.intervalId = null;
+    this.flushTimeout = this.flushTimeout || (Date.now() + defaultFlushTimeoutMs);
+
+    this.submit(((error) => {    
+      if (error) return callback(error);
+      if (isEmpty(this.logEvents)) return callback();
+      if (Date.now() > this.flushTimeout) return callback(new Error('Timeout reached while waiting for logs to submit'));
+      else setTimeout(this.kthxbye.bind(this, callback), 0);
+    }));
   }
-};
-
-WinstonCloudWatch.prototype.submit = function(callback) {
-  var groupName = typeof this.logGroupName === 'function' ?
-    this.logGroupName() : this.logGroupName;
-  var streamName = typeof this.logStreamName === 'function' ?
-    this.logStreamName() : this.logStreamName;
-  var retentionInDays = this.retentionInDays;
 
-  if (isEmpty(this.logEvents)) {
-    return callback();
+  setOptions(options) {
+    this.level = options.level || 'info';
+    this.name = options.name || 'CloudWatch';
+    this.logGroupName = options.logGroupName;
+    this.retentionInDays = options.retentionInDays || 0;
+    this.logStreamName = options.logStreamName;
+
+    var awsAccessKeyId = options.awsAccessKeyId;
+    var awsSecretKey = options.awsSecretKey;
+    var awsRegion = options.awsRegion;
+    var messageFormatter = options.messageFormatter ?
+        options.messageFormatter : (log) => log[MESSAGE]
+    this.formatMessage = options.jsonMessage ? stringify : messageFormatter;
+    this.proxyServer = options.proxyServer;
+    this.uploadRate = options.uploadRate || 2000;
+    this.logEvents = [];
+    this.errorHandler = options.errorHandler;
+
+    if (options.cloudWatchLogs) {
+      this.cloudwatchlogs = options.cloudWatchLogs;
+    } else {
+      if (this.proxyServer) {
+        AWS.config.update({
+          httpOptions: {
+            agent: require('proxy-agent')(this.proxyServer)
+          }
+        });
+      }
+
+      var config = {};
+
+      if (awsAccessKeyId && awsSecretKey && awsRegion) {
+        config = { accessKeyId: awsAccessKeyId, secretAccessKey: awsSecretKey, region: awsRegion };
+      } else if (awsRegion && !awsAccessKeyId && !awsSecretKey) {
+        // Amazon SDK will automatically pull access credentials
+        // from IAM Role when running on EC2 but region still
+        // needs to be configured
+        config = { region: awsRegion };
+      }
+
+      if (options.awsOptions) {
+        config = assign(config, options.awsOptions);
+      }
+
+      this.cloudwatchlogs = new AWS.CloudWatchLogs(config);
+    }
   }
-
-  cloudWatchIntegration.upload(
-    this.cloudwatchlogs,
-    groupName,
-    streamName,
-    this.logEvents,
-    retentionInDays,
-    callback
-  );
-};
-
-WinstonCloudWatch.prototype.kthxbye = function(callback) {  
-  clearInterval(this.intervalId);
-  this.intervalId = null;
-  this.flushTimeout = this.flushTimeout || (Date.now() + defaultFlushTimeoutMs);
-
-  this.submit((function(error) {    
-    if (error) return callback(error);
-    if (isEmpty(this.logEvents)) return callback();
-    if (Date.now() > this.flushTimeout) return callback(new Error('Timeout reached while waiting for logs to submit'));
-    else setTimeout(this.kthxbye.bind(this, callback), 0);
-  }).bind(this));
-};
-
-winston.transports.CloudWatch = WinstonCloudWatch;
-
-module.exports = WinstonCloudWatch;
+}

package.json

@@ -20,7 +20,8 @@
   "license": "MIT",
   "typings": "typescript/winston-cloudwatch.d.ts",
   "peerDependencies": {
-    "winston": "^3.0.0"
+    "winston": "^3.0.0",
+    "winston-transport": "^4.3.0"
   },
   "dependencies": {
     "async": "^3.1.0",
@@ -31,7 +32,8 @@
     "lodash.find": "^4.6.0",
     "lodash.isempty": "^4.4.0",
     "lodash.iserror": "^3.1.1",
-    "proxy-agent": "^3.1.1"
+    "proxy-agent": "^3.1.1",
+    "triple-beam": "^1.3.0"
   },
   "devDependencies": {
     "@types/node": "13.11.0",

test/index.js

@@ -1,9 +1,27 @@
-describe('index', function() {
+var sinon = require('sinon'),
+    should = require('should'),
+    mockery = require('mockery');
+
+
+// the following does not, and should not, mock winston,
+// to actually test the transport
+describe.only('Transport', function() {
 
-  var sinon = require('sinon'),
-      should = require('should'),
-      mockery = require('mockery');
+  var winston = require('winston'),
+      WinstonCloudWatch = require('../index.js'),
+      clock = sinon.useFakeTimers(),
+      Transport = require('winston-transport'),
+      transport;
 
+  it('should derive from Winston transport', function() {
+    transport = new WinstonCloudWatch({});
+    transport.should.be.an.instanceOf(Transport)
+  });
+});
+
+describe('index', function() {
+
+  // TODO check that the API is still this one
   var stubbedWinston = {
     transports: {},
     Transport: function() {}
@@ -303,5 +321,4 @@ describe('index', function() {
       clock.tick(1);
     });
   });
-
 });