mongo-select

Module to help create projection objects when working with mongodb.

Installing

npm install mongo-select

Introduction

var select = require('mongo-select').select();
var mongodb = require('mongodb');
 
var MongoClient = mongodb.MongoClient;
 
MongoClient.connect('mongodb://127.0.0.1:27017/test', function(err, db) {
  if(err) throw err;
 
  var users = db.collection('users');
  scripts = users.find({}, select.include(['name', 'email']), 
    function(err, result){
      // code here, access to only result[i]._id, result[i].name and result[i].email
    });
});

Examples

Including fields

var select = require('mongo-select').select();
 
var projection = select.include(['name', 'email', 'children.name']).make();
 
console.log(projection); // { 'name': false, 'email': false, 'children.name': false };

Excluding fields

var select = require('mongo-select').select();
 
var projection = select.exclude(['name', 'email', 'children.name']);
 
console.log(projection); // { 'name': false, 'email': false, 'children.name': false };

Excluding _id

var select = require('mongo-select').select();
 
var projection = select.noId();
 
console.log(projection); // { '_id': false };

Chaining

To provide a fluent interface the chaining methods begin with _. Otherwise this might affect documents with fields named exclude, include, noId.

var select = require('mongo-select').select();
 
var projection = select.noId()._exclude(['name', 'email', 'children.name']);
 
console.log(projection); // { '_id': false, 'name': false, 'email': false, 'children.name': false };

var select = require('mongo-select').select();
 
var projection = select.include(['name', 'email', 'children.name'])._noId();
 
console.log(projection); // { '_id': false, 'name': true, 'email': true, 'children.name': true };

Permanent exclusion/inclusion

Sometimes it is important to always exclude or include a set of fields. That means that if they are permanently excluded and then specifically included they won't make it into the projection and viceversa:

var select = require('mongo-select').select();
 
select.exclude(['name', 'email', 'children.name'])._always();
 
var exclusion = select.exclude(['address']);
 
console.log(exclusion); // { 'name': false, 'email': false, 'children.name': false };
 
var inclusion = select.include(['name', 'email']);
 
console.log(inclusion); // { };

To clear permanent registrations simply

select.clear();

Contributing

Pull requests and issues are more than welcome. When submitting a PR make sure to run the tests:

npm test