Version 1.1.0 released:

* added support of passing promises objects which will be resolved with
pre-connected db object in options.db;
* fixed issue when events logged sometime between authorizeDb and
processOpQuery calls may be lost;
* renamed default log collection to 'log' because it makes more sense than
'logs' ('log' is a list of messages already, plural form would imply
multiple of such lists);
* this.mainDb renamed to this.logDb;
* this._opQuery renamed to this._opQueue;
* added test to promises support (bluebird added to devDependencies as A+ promises implementation).

Author: yurijmikhalevich

README.md

@@ -34,11 +34,12 @@ The MongoDB transport takes the following options. 'db' is required:
 'info'.
 * __silent:__ Boolean flag indicating whether to suppress output, defaults to
 false.
-* __db:__ MongoDB connection uri or preconnected db object.
+* __db:__ MongoDB connection uri, pre-connected db object or promise object
+which will be resolved with pre-connected db object.
 * __options:__ MongoDB connection parameters (optional, defaults to
 `{db: {native_parser: true}, server: {poolSize: 2, socketOptions: {autoReconnect: true}}}`).
 * __collection__: The name of the collection you want to store log messages in,
-defaults to 'logs'.
+defaults to 'log'.
 * __storeHost:__ Boolean indicating if you want to store machine hostname in
 logs entry, if set to true it populates MongoDB entry with 'hostname' field,
 which stores os.hostname() value.
@@ -74,11 +75,21 @@ settled by mongodb, defaults to `false`.
 
 ## Changelog
 
+### Brief 1.1.0 changelog
+
+* added support of passing promises objects which will be resolved with
+pre-connected db object in options.db;
+* fixed issue when events logged sometime between authorizeDb and
+processOpQuery calls may be lost;
+* renamed default log collection to 'log' because it makes more sense than
+'logs' ('log' is a list of messages already, plural form would imply
+multiple of such lists).
+
 ### Brief 1.0.0 changelog
 
 * migrated to mongodb 2.x driver;
 * changed configuration format to MongoDB uri string;
-* added support of passing preconnected db object instead of MongoDB uri string;
+* added support of passing pre-connected db object instead of MongoDB uri string;
 * added support of passing MongoDB connection parameters in options property;
 * added support of replica sets through new options and db properties;
 * migrated to [Semantic Versioning](http://semver.org/) in package versions names;

lib/winston-mongodb.js

@@ -63,7 +63,7 @@ var MongoDB = exports.MongoDB = function(options) {
       }
     };
   }
-  this.collection = (options.collection || 'logs');
+  this.collection = (options.collection || 'log');
   this.level = (options.level || 'info');
   this.silent = options.silent;
   this.username = options.username;
@@ -77,47 +77,55 @@ var MongoDB = exports.MongoDB = function(options) {
     this.hostname = os.hostname();
   }
 
-
-  this._opQuery = [];
+  this._opQueue = [];
 
   var self = this;
 
-  function processOpQuery() {
-    self._opQuery.forEach(function(operation) {
+  function setupDatabaseAndEmptyQueue(db) {
+    authorizeDb(db, function(err, db) {
+      createCollection(db, function(err, db) {
+        self.logDb = db;
+        processOpQueue();
+      });
+    });
+  }
+
+  function processOpQueue() {
+    self._opQueue.forEach(function(operation) {
       self[operation.method].apply(self, operation.args);
     });
-    delete self._opQuery;
+    delete self._opQueue;
   }
 
-  function createCollection(cb) {
+  function createCollection(db, cb) {
     var opts = {};
     if (self.capped) {
       opts = {capped: true, size: self.cappedSize};
     }
-    self.mainDb.createCollection(self.collection, opts, function() {
-      cb(null);
+    db.createCollection(self.collection, opts, function() {
+      cb(null, db);
     });
   }
 
-  function authorizeDb(cb) {
+  function authorizeDb(db, cb) {
     if (self.username && self.password) {
-      self.mainDb.authenticate(self.username, self.password,
+      db.authenticate(self.username, self.password,
           function(err, result) {
             if (err) {
               console.error('winston-mongodb: error initialising logger', err);
-              self.mainDb.close();
+              db.close();
               return;
             }
             if (!result) {
               console.error('winston-mongodb: invalid username or password');
-              self.mainDb.close();
+              db.close();
               return;
             }
-            cb(null);
+            cb(null, db);
           }
       );
     }
-    cb(null);
+    cb(null, db);
   }
 
   if ('string' === typeof this.db) {
@@ -126,16 +134,17 @@ var MongoDB = exports.MongoDB = function(options) {
         console.error('winston-mongodb: error initialising logger', err);
         return;
       }
-      self.mainDb = db;
-      authorizeDb(function() {
-        createCollection(processOpQuery);
-      });
+      setupDatabaseAndEmptyQueue(db);
     });
-  } else {
-    this.mainDb = this.db;
-    authorizeDb(function() {
-      createCollection(processOpQuery);
+  } else if ('function' === typeof this.db.then) {
+    this.db.then(function(db) {
+      setupDatabaseAndEmptyQueue(db);
+    }, function(err) {
+      console.error(
+          'winston-mongodb: error initialising logger from promise', err);
     });
+  } else {
+    setupDatabaseAndEmptyQueue(this.db);
   }
 };
 
@@ -161,8 +170,8 @@ winston.transports.MongoDB = MongoDB;
  * @param {Function} callback Continuation to respond to when complete.
  */
 MongoDB.prototype.log = function(level, msg, opt_meta, callback) {
-  if (!this.mainDb) {
-    this._opQuery.push({
+  if (!this.logDb) {
+    this._opQueue.push({
       method: 'log',
       args: arguments
     });
@@ -186,7 +195,7 @@ MongoDB.prototype.log = function(level, msg, opt_meta, callback) {
       callback(err, null);
     }
 
-    self.mainDb.collection(self.collection, function(err, col) {
+    self.logDb.collection(self.collection, function(err, col) {
       if (err) {
         onError(err);
         return;
@@ -225,8 +234,8 @@ MongoDB.prototype.log = function(level, msg, opt_meta, callback) {
  * @return {*}
  */
 MongoDB.prototype.query = function(opt_options, callback) {
-  if (!this.mainDb) {
-    this._opQuery.push({
+  if (!this.logDb) {
+    this._opQueue.push({
       method: 'query',
       args: arguments
     });
@@ -257,7 +266,7 @@ MongoDB.prototype.query = function(opt_options, callback) {
     opt.fields = options.fields;
   }
 
-  this.mainDb.collection(this.collection, function(err, col) {
+  this.logDb.collection(this.collection, function(err, col) {
     if (err) {
       callback(err);
       return;
@@ -293,8 +302,8 @@ MongoDB.prototype.stream = function(options, stream) {
   var self = this;
   var start = options.start;
 
-  if (!this.mainDb) {
-    this._opQuery.push({
+  if (!this.logDb) {
+    this._opQueue.push({
       method: 'stream',
       args: [options, stream]
     });
@@ -310,7 +319,7 @@ MongoDB.prototype.stream = function(options, stream) {
   }
 
   if (start != null) {
-    this.mainDb.collection(this.collection, function(err, col) {
+    this.logDb.collection(this.collection, function(err, col) {
       if (err) {
         stream.emit('error', err);
         return;
@@ -334,7 +343,7 @@ MongoDB.prototype.stream = function(options, stream) {
     return stream;
   }
 
-  this.mainDb.collection(this.collection, function(err, col) {
+  this.logDb.collection(this.collection, function(err, col) {
     if (err) {
       stream.emit('error', err);
       return;
@@ -387,8 +396,8 @@ MongoDB.prototype.streamPoll = function(options, stream) {
   var start = options.start;
   var last;
 
-  if (!this.mainDb) {
-    this._opQuery.push({
+  if (!this.logDb) {
+    this._opQueue.push({
       method: 'streamPoll',
       args: [options, stream]
     });
@@ -408,7 +417,7 @@ MongoDB.prototype.streamPoll = function(options, stream) {
   };
 
   (function check() {
-    self.mainDb.collection(self.collection, function(err, col) {
+    self.logDb.collection(self.collection, function(err, col) {
       if (err) {
         stream.emit('error', err);
         return;

package.json

@@ -1,7 +1,7 @@
 {
   "name": "winston-mongodb",
   "license": "MIT",
-  "version": "1.0.1",
+  "version": "1.1.0",
   "description": "A MongoDB transport for winston",
   "author": "Charlie Robbins <[email protected]>",
   "contributors": [
@@ -19,7 +19,8 @@
   },
   "devDependencies": {
     "winston": "0.9.x",
-    "vows": "0.8.x"
+    "vows": "0.8.x",
+    "bluebird": "2.9.x"
   },
   "main": "./lib/winston-mongodb",
   "scripts": { "test": "vows test/*-test.js --spec" }

test/winston-mongodb-test.js

@@ -7,17 +7,33 @@
  */
 
 var vows = require('vows');
+var mongodb = require('mongodb');
+var Promise = require('bluebird');
 var transport = require('winston/test/transports/transport');
 var MongoDB = require('../lib/winston-mongodb').MongoDB;
 
 vows.describe('winston-mongodb').addBatch({
   'An instance of the MongoDB Transport': transport(MongoDB, {
     db: 'mongodb://localhost/winston'
   }),
-  'And instance of the MongoDB Transport on capped collection':
+  'An instance of the MongoDB Transport on capped collection':
       transport(MongoDB, {
         db: 'mongodb://localhost/winston',
         capped: true,
-        collection: 'cappedLogs'
+        collection: 'cappedLog'
+      })
+}).addBatch({
+  'An instance of the MongoDB Transport with promise':
+      transport(MongoDB, {
+        db: new Promise(function(resolve, reject) {
+          mongodb.MongoClient.connect('mongodb://localhost/winston',
+              function(err, db) {
+                if (err) {
+                  reject(err);
+                } else {
+                  resolve(db);
+                }
+              });
+        })
       })
 }).export(module);