mongo-mock     

This is an in-memory 'pretend' mongodb. The goal is to make the interface compatible with the real mongodb module so they are interchangeable.

There are a TON of features for mongo and I can't write them all myself- so pull requests are encouraged! My initial goal was to provide basic CRUD operations to enable this to work as a throw-something-together tool.

Why?

Maybe you don't want to (or can't) connect to a MongoDB instance for your tests?
Maybe you want to throw together a quick example app?

Demo code

var mongodb = require('mongo-mock');
mongodb.max_delay = 0;//you can choose to NOT pretend to be async (default is 400ms)
var MongoClient = mongodb.MongoClient;
MongoClient.persist="mongo.js";//persist the data to disk

// Connection URL
var url = 'mongodb://localhost:27017/myproject';
// Use connect method to connect to the Server
MongoClient.connect(url, {}, function(err, client) {
  var db = client.db();
  // Get the documents collection
  var collection = db.collection('documents');
  // Insert some documents
  var docs = [ {a : 1}, {a : 2}, {a : 3}];
  collection.insertMany(docs, function(err, result) {
    console.log('inserted',result);

    collection.updateOne({ a : 2 }, { $set: { b : 1 } }, function(err, result) {
      console.log('updated',result);

      collection.findOne({a:2}, {b:1}, function(err, doc) {
        console.log('foundOne', doc);

        collection.removeOne({ a : 3 }, function(err, result) {
          console.log('removed',result);

          collection.find({}, {_id:-1}).toArray(function(err, docs) {
            console.log('found',docs);
            
            function cleanup(){            
              var state = collection.toJSON();
              // Do whatever you want. It's just an Array of Objects.
              state.documents.push({a : 2});
              
              // truncate
              state.documents.length = 0;
              
              // closing connection
              db.close();
            }
            
            setTimeout(cleanup, 1000);
          });
        });
      });
    });
  });
});

Install

Well, you know.. the usual:

$ npm install mongo-mock