mambo

The best document mapper for DynamoDB.

Example

var mambo = require('mambo'),
    Schema = mambo.Schema,
    StringField = mambo.StringField,
    NumberField = mambo.NumberField,
    JSONField = mambo.JSONField,
    DateField = mambo.DateField;

var Comment = new mambo.Model(new Schema(
        'Comments', 'comments', ['post_id', 'created'],
        {
            'post_id': NumberField,
            'created': DateField,
            'comment': StringField,
            'author': StringField,
            'liked_by': JSONField
        }
    ), new Schema('Users', 'users', 'username', {
        'username': StringField,
        'name': StringField,
        'lastCommentPosted': DateField
    })
);

Comment.getAll = function(postId){
    this.objects('comments', postId)
        .limit(5)
        .fetch(function(err, comments){
            console.log('Comments for post ' + postId + ':\n'); console.log(JSON.stringify(comments, null, 4));
        });
};

Comment.post = function(postId, author, comment){
    this.insert('comments', {
        'post_id': postId,
        'created': new Date(),
        'author': author,
        'comment': comment,
        'liked_by': []
    })
    .commit(function(err, res){
        console.log('Comment added!');
    });
};

module.exports = Comment;

Plugins

Distributed Locks

Mutex provides a simple TTL lock like ddbsync, as described in Distributed Locking With DynamoDB

var Mutex = require('mambo').Mutex,
    mutex = new Mutex('some-name', 10);
mutex.lock(function(err){
    if(err) return console.error('Couldn\'t accquire lock');
    // Do some stuff
    mutex.unlock(function(){
        console.log('Unlocked.  Lock away.');
    });
});

Experimental

Sorted Sets

Thanks to the new local secondary indexes, you can implement a sorted set in dynamo like you can with Redis.

var SortedSet = require('mambo').SortedSet,
    d = new Date(),
    songLoves = new SortedSet('loves-' + [
        d.getYear(), d.getMonth(), d.getDay()].join('-'));

songLoves.incryby(1, 2, function(){
    songLoves.incryby(2, 1, function(){
        songLoves.incryby(3, 9, function(){
            songLoves.incryby(3, 1, function(){
                songLoves.range(0, 3, function(err, ids){
                    assert.deepEqual(ids, [3, 1, 2]);
                });
            });
        });
    });
});

Install

 npm install mambo

Testing

git clone
npm install
npm test