bole-mongodb

MongoDB stream for the bole logger

Plugin for the bole logger. Saves the logs to a MongoDB collection, log by default.

var bole = require ("bole");
var boleMongo = require ("bole-mongodb");

var url = ...

MongoClient.connect (url, function (error, db){
  if (error) return console.error (error);
  
  var boleMongoStream = boleMongo ({ db: db, capped: true })
    //The error handler shouldn't be called. If it is called, then something is
    //wrong with the database url or connection options, so it's up to you
    //how to handle these kind of errors: crashing the server (without
    //registering this error handler) or logging it somewhere
    .on ("error", console.error);
  
  bole.output ([
    { level: 'error', stream: boleMongoStream }
  ]);
  
  ...
 });

The Db object is required. Instead of opening a new connection from inside the plugin, the user is responsible for the connection's lifecycle. Therefore, this plugin assumes that the connection is already open. However, it won't fail if it's not.

MongoDB has the concept of a Capped collection and it can be used for logging purposes. This plugin tries to create a capped collection for the first time a message is logged, and it can be forced to convert an existing one into a capped collection.

module(options) : Writable

Returns a new Writable stream instance.

Options:

• db - Object
  MongoDB Db instance. This option is mandatory.
• collection - String
  Name of the collection. Default "log".
• capped - Boolean
  If the collection doesn't exist, creates a new capped collection. Default false.
• size - Number
  Size of the capped collection. Default 10000000 (10MB rounded up to the nearest multiple of 256).
• max - Number
  Maximum number of documents allowed in the capped collection. Default undefined.
• force - Boolean
  If the collection already exists, it is converted into a capped collection. Default false.