sequelize-connect

sequelize-connect

Formerly sequelize-singleton.

sequelize-connect is a simple singleton wrapper for the sequelize ORM, making it easier to configure and build models with Sequelize.

• Configuring sequelize-connect
  • Connection String
• Custom Matcher
• Accessing Sequelize
• Defining Models
• Logging
• Contributing

Configuring sequelize-connect

NOTE: sequelize-connect must be configured upon app initialization, prior to accessing your models

The sequelize-connect connect() method accepts the same parameters as the Sequelize() object database, username, password, options.

// app.js
var Connection 		= require('sequelize-connect');

var orm = new Connection(
  'test-db',
  'test-user',
  'secret1234',
  {
    dialect: "mysql",
    port:    3306
  }
)
.then(function(instance){
  // Connection is completed
});

It is important to configure the discover array of the set of paths where your models should be discovered.

// app.js
var Connection 		= require('sequelize-connect');

var discover = [__dirname + '/models', ...];
var orm = new Connection(
  'test-db',
  'test-user',
  'secret1234',
  {
    dialect: "mysql",
    port:    3306
  },
  discover,
)
.then(function(instance){
  // Connection is completed
});

Upon the first initialization of the Connection e.g. new Connection(...); sequelize-connect will ASYNCHRONOUSLY recurse through all of the subfolders located at the provided file paths looking for any files with the naming default convention *.model.js. Connect will return a Promise that is called on it's completion.

Connection String

You can use a connection string to connect as well:

new Connection(
  'MyConnectionString',
  {
    dialect: "mysql",
    port:    3306
  })
  .then(function(){
    // Connection is completed
  });

Custom matcher

If you prefer to define your own naming convention instead of the default you can create a custom matching function which receives the file name as the parameter returns a boolean indicating if sequelize-connect should attempt to load the file as a model.

This function should be injected to Connection like so:

var matcher = function(file){
  if(//some condition or regex here)
    return true;

  return false;
};

new Connection(
  'test-db',
  'test-user',
  'secret1234',
  {
    dialect: "mysql",
    port:    3306
  },
  discover,
  matcher
)

Accessing sequelize

After connecting you can access the sequelize instance and models wherever you need!

// somefile.js

var Connection = require('sequelize-connect');
var orm = new Connection(); // singleton pattern - returns the created instance
var sequelize = orm.sequelize;
var Sequelize = orm.Sequelize;
var models    = orm.models;
var User      = models.User;

If you prefer, rather than waiting for the connection to load before initializing every part of your application, you can wrap the code that has dependencies on your models in a then. e.g.

// app.js
new Connection(
  'MyConnectionString',
  {
    dialect: "mysql",
    port:    3306
  })

// foobar.js

var Promise = require('bluebird');
var Connection = require('sequelize-connect');
var orm = new Connection();

// This will ensure that the connection has been established
// if you load foobar.js before you wait for your initial connection
// to return
var Promise.resolve(orm)
  .then(function(instance) {
    var User = instance.models.Foo;

    /**
     * Get list of users
     * restriction: 'admin'
     */
    var index = function(req, res) {
      Foo.bar()
    };
  })

Defining Models

Models are defined as per the suggestion the article here: http://sequelizejs.com/articles/express. All associations are done via the class method associate which is injected with the models object.

// user.model.js
"use strict";

module.exports = function(sequelize, DataTypes) {
  var User = sequelize.define("User", {
    username: DataTypes.STRING
  });

  // class association method
  User.associate = function(models) {
    User.hasMany(models.Task);
  }

  return User;
};

Logging

Logging is optional, but is turned off by default. In order to enable logging, simply inject the logger of your choice:

myLogger = console;
// myLogger = winston;
// myLogger = ...;

new Connection(
  'test-db',
  'test-user',
  'secret1234',
  {
    dialect: "mysql",
    port:    3306
  },
  discover,
  matcher,
  myLogger
)

Your logger must comply with the following interface:

logger.log(level, message);

Contributing

Please read the contributing guidlines