asteroid

v0.7.0

Install

slnode install asteroid -g

Server API

• App
• Model
• DataSource
• Connectors
• GeoPoint
• Asteroid Types
• REST Router

Client API

TODO

App

Create an asteroid application.

var asteroid = require('asteroid');
var app = asteroid();

app.get('/', function(req, res){
  res.send('hello world');
});

app.listen(3000);

Notes:

• extends express
• see express docs for details
• supports express / connect middleware

app.model(Model)

Expose a Model to remote clients.

var memory = asteroid.createDataSource({connector: asteroid.Memory});
var Color = memory.createModel('color', {name: String});

app.model(Color);
app.use(asteroid.rest());

Note: this will expose all shared methods on the model.

app.models()

Get the app's exposed models.

var models = app.models();

models.forEach(function (Model) {
  console.log(Model.modelName); // color
});

Model

An Asteroid Model is a vanilla JavaScript class constructor with an attached set of properties and options. A Model instance is created by passing a data object containing properties to the Model constructor. A Model constructor will clean the object passed to it and only set the values matching the properties you define.

// valid color
var Color = asteroid.createModel('color', {name: String});
var red = new Color({name: 'red'});
console.log(red.name); // red

// invalid color
var foo = new Color({bar: 'bat baz'});
console.log(foo.bar); // undefined

Properties

A model defines a list of property names, types and other validation metadata. A DataSource uses this definition to validate a Model during operations such as save().

Options

Some DataSources may support additional Model options.

Define an asteroid model.

var User = asteroid.createModel('user', {
  first: String,
  last: String,
  age: Number
});

Model.validatesPresenceOf(properties...)

Require a model to include a property to be considered valid.

User.validatesPresenceOf('first', 'last', 'age');

Model.validatesLengthOf(property, options)

Require a property length to be within a specified range.

User.validatesLengthOf('password', {min: 5, message: {min: 'Password is too short'}});

Model.validatesInclusionOf(property, options)

Require a value for property to be in the specified array.

User.validatesInclusionOf('gender', {in: ['male', 'female']});

Model.validatesExclusionOf(property, options)

Require a value for property to not exist in the specified array.

User.validatesExclusionOf('domain', {in: ['www', 'billing', 'admin']});

Model.validatesNumericalityOf(property, options)

Require a value for property to be a specific type of Number.

User.validatesNumericalityOf('age', {int: true});

Model.validatesUniquenessOf(property, options)

Ensure the value for property is unique.

User.validatesUniquenessOf('email', {message: 'email is not unique'});

Note: not available for all connectors.

myModel.isValid()

Validate the model instance.

user.isValid(function (valid) {
    if (!valid) {
        user.errors // hash of errors {attr: [errmessage, errmessage, ...], attr: ...}    
    }
});

Model.attachTo(dataSource)

Attach a model to a DataSource. Attaching a DataSource updates the model with additional methods and behaviors.

var oracle = asteroid.createDataSource({
  connector: require('asteroid-oracle'),
  host: '111.22.333.44',
  database: 'MYDB',
  username: 'username',
  password: 'password'
});

User.attachTo(oracle);

Note: until a model is attached to a data source it will not have any attached methods.

Attached Methods

Attached methods are added by attaching a vanilla model to a data source with a connector. Each connector enables its own set of operations that are attached to a Model as methods. To see available methods for a data source with a connector call dataSource.operations().

Model.create([data], [callback])

Create an instance of Model with given data and save to the attached data source.

User.create({first: 'Joe', last: 'Bob'}, function(err, user) {
  console.log(user instanceof User); // true
});

model.save([options], [callback])

Save an instance of a Model to the attached data source.

var joe = new User({first: 'Joe', last: 'Bob'});
joe.save(function(err, user) {
  if(user.errors) {
    console.log(user.errors);
  } else {
    console.log(user.id);
  }
});

model.updateAttributes(data, [callback])

Save specified attributes to the attached data source.

user.updateAttributes({
  first: 'updatedFirst',
  name: 'updatedLast'
}, fn);

Model.upsert(data, callback)

Update when record with id=data.id found, insert otherwise. Note: no setters, validations or hooks applied when using upsert.

model.destroy([callback])

Remove a model from the attached data source.

model.destroy(function(err) {
  // model instance destroyed
});

Model.destroyAll(callback)

Delete all Model instances from data source. Note: destroyAll method does not perform destroy hooks.

Model.find(id, callback)

Find instance by id.

User.find(23, function(err, user) {
  console.info(user.id); // 23
});

Model.all(filter, callback);

Find all instances of Model, matched by query. Fields used for filter and sort should be declared with {index: true} in model definition.

filter

• where Object { key: val, key2: {gt: 'val2'}}
• include String, Object or Array.
• order String
• limit Number
• skip Number

Find the second page of 10 users over age 21 in descending order.

User.all({where: {age: {gt: 21}}, order: 'age DESC', limit: 10, skip: 10})

Note: See the specific connector's docs for more info.

Model.count([query], callback)

Query count of Model instances in data source. Optional query param allows to count filtered set of Model instances.

User.count({approved: true}, function(err, count) {
  console.log(count); // 2081
});

Static Methods

Define a static model method.

User.login = function (username, password, fn) {
  var passwordHash = hashPassword(password);
  this.findOne({username: username}, function (err, user) {
    var failErr = new Error('login failed');

    if(err) {
      fn(err);
    } else if(!user) {
      fn(failErr);
    } else if(user.password === passwordHash) {
      MySessionModel.create({userId: user.id}, function (err, session) {
        fn(null, session.id);
      });
    } else {
      fn(failErr);
    }
  });
}

Setup the static model method to be exposed to clients as a remote method.

asteroid.remoteMethod(
  User.login,
  {
    accepts: [
      {arg: 'username', type: 'string', required: true},
      {arg: 'password', type: 'string', required: true}
    ],
    returns: {arg: 'sessionId', type: 'any'},
    http: {path: '/sign-in'}
  }
);

Instance Methods

Define an instance method.

User.prototype.logout = function (fn) {
  MySessionModel.destroyAll({userId: this.id}, fn);
}

Define a remote model instance method.

asteroid.remoteMethod(User.prototype.logout);

Remote Methods

Both instance and static methods can be exposed to clients. A remote method must accept a callback with the conventional fn(err, result, ...) signature.

asteroid.remoteMethod(fn, [options]);

Expose a remote method.

Product.stats = function(fn) {
  myApi.getStats('products', fn);
}

asteroid.remoteMethod(
  Product.stats,
  {
    returns: {arg: 'stats', type: 'array'},
    http: {path: '/info', verb: 'get'}
  }
);

Options

• accepts - (optional) an arguments description specifying the remote method's arguments. A
• returns - (optional) an arguments description specifying the remote methods callback arguments.
• http - (advanced / optional, object) http routing info
• http.path - the relative path the method will be exposed at. May be a path fragment (eg. '/:myArg') which will be populated by an arg of the same name in the accepts description.
• http.verb - (get, post, put, del, all) - the route verb the method will be available from.

Argument Description

An arguments description defines either a single argument as an object or an ordered set of arguments as an array.

// examples
{arg: 'myArg', type: 'number'}

[
  {arg: 'arg1', type: 'number', required: true},
  {arg: 'arg2', type: 'array'}
]

Types

Each argument may define any of the asteroid types.

Notes:

• The callback is an assumed argument and does not need to be specified in the accepts array.
• The err argument is also assumed and does not need to be specified in the returns array.

Remote Hooks

Run a function before or after a remote method is called by a client.

// *.save === prototype.save
User.beforeRemote('*.save', function(ctx, user, next) {
  if(ctx.user) {
    next();
  } else {
    next(new Error('must be logged in to update'))
  }
});

User.afterRemote('*.save', function(ctx, user, next) {
  console.log('user has been saved', user);
  next();
});

Remote hooks also support wildcards. Run a function before any remote method is called.

// ** will match both prototype.* and *.*
User.beforeRemote('**', function(ctx, user, next) {
  console.log(ctx.methodString, 'was invoked remotely'); // users.prototype.save was invoked remotely
  next();
});

Other wildcard examples

// run before any static method eg. User.all
User.beforeRemote('*', ...);

// run before any instance method eg. User.prototype.save
User.beforeRemote('prototype.*', ...);

// prevent password hashes from being sent to clients
User.afterRemote('**', function (ctx, user, next) {
  if(ctx.result) {
    if(Array.isArray(ctx.result)) {
      ctx.result.forEach(function (result) {
        result.password = undefined;
      });
    } else {
      ctx.result.password = undefined;
    }
  }

  next();
});

Context

Remote hooks are provided with a Context ctx object which contains transport specific data (eg. for http: req and res). The ctx object also has a set of consistent apis across transports.

ctx.user

A Model representing the user calling the method remotely. Note: this is undefined if the remote method is not invoked by a logged in user.

ctx.result

During afterRemote hooks, ctx.result will contain the data about to be sent to a client. Modify this object to transform data before it is sent.

Rest

When asteroid.rest is used the following ctx properties are available.

ctx.req

The express ServerRequest object. See full documentation.

ctx.res

The express ServerResponse object. See full documentation.

Access the raw req object for the remote method call.

Relationships

Model.hasMany(Model)

Define a "one to many" relationship.

// by referencing model
Book.hasMany(Chapter);
// specify the name
Book.hasMany('chapters', {model: Chapter});

Query and create the related models.

Book.create(function(err, book) {
  // using 'chapters' scope for build:
  var c = book.chapters.build({name: 'Chapter 1'});
  
  // same as:
  c = new Chapter({name: 'Chapter 1', bookId: book.id});
  
  // using 'chapters' scope for create:
  book.chapters.create();
  
  // same as:
  Chapter.create({bookId: book.id});

  // using scope for querying:
  book.chapters(function(err, chapters) {
    /* all chapters with bookId = book.id */
  });
  
  book.chapters({where: {name: 'test'}, function(err, chapters) {
    // all chapters with bookId = book.id and name = 'test'
  });
});

Model.hasAndBelongsToMany()

TODO: implement / document

Shared Methods

Any static or instance method can be decorated as shared. These methods are exposed over the provided transport (eg. asteroid.rest).

Data Source

An Asteroid DataSource provides Models with the ability to manipulate data. Attaching a DataSource to a Model adds instance methods and static methods to the Model. The added methods may be remote methods.

Define a data source for persisting models.

var oracle = asteroid.createDataSource({
  connector: 'oracle',
  host: '111.22.333.44',
  database: 'MYDB',
  username: 'username',
  password: 'password'
});

dataSource.createModel(name, properties, options)

Define a model and attach it to a DataSource.

var Color = oracle.createModel('color', {name: String});

dataSource.discoverAndBuildModels(owner, tableOrView, options, fn)

Discover a set of models based on tables or collections in a data source.

oracle.discoverAndBuildModels('MYORG', function(err, models) {
  var ProductModel = models.Product;
});

Note: The models will contain all properties and options discovered from the data source. It will also automatically discover and create relationships.

dataSource.discoverAndBuildModelsSync(owner, tableOrView, options)

Synchronously Discover a set of models based on tables or collections in a data source.

var models = oracle.discoverAndBuildModelsSync('MYORG');
var ProductModel = models.Product;

dataSource.discoverModelDefinitions([owner], fn)

Discover a set of model definitions based on tables or collections in a data source.

oracle.discoverModelDefinitions(null, function (err, models) {
  models.forEach(function (def) {
    // def.name ~ the model name
    oracle.discoverSchema(null, def.name, function (err, schema) {
      console.log(schema);
    });
  });
});

dataSource.discoverSchema([owner], name, fn)

Discover the schema of a data source.

dataSource.defineOperation(name, options, fn)

Define a new operation available to all model's attached to the data source.

var maps = asteroid.createDataSource({
  connector: require('asteroid-rest'),
  url: 'http://api.googleapis.com/maps/api'
});

rest.defineOperation('geocode', {
  url: '/geocode/json',
  verb: 'get',
  accepts: [
    {arg: 'address', type: 'string'},
    {arg: 'sensor', default: 'true'}
  ],
  returns: {arg: 'location', type: asteroid.GeoPoint, transform: transform},
  json: true,
  enableRemote: true
});

function transform(res) {
  var geo = res.body.results[0].geometry;
  return new asteroid.GeoPoint({lat: geo.lat, long: geo.lng});
}

var GeoCoder = rest.createModel('geocoder');

GeoCoder.geocode('123 fake street', function(err, point) {
  console.log(point.lat, point.long); // 24.224424 44.444445
});

dataSource.enableRemote(operation)

Enable remote access to a data source operation. Each connector has its own set of set remotely enabled and disabled operations. You can always list these by calling dataSource.operations().

dataSource.disableRemote(operation)

Disable remote access to a data source operation. Each connector has its own set of set enabled and disabled operations. You can always list these by calling dataSource.operations().

// all rest data source operations are
// disabled by default
var oracle = asteroid.createDataSource({
  connector: require('asteroid-oracle'),
  host: '...',
  ...
});

// or only disable it as a remote method
oracle.disableRemote('destroyAll');

Notes:

• disabled operations will not be added to attached models
• disabling the remoting for a method only affects client access (it will still be available from server models)
• data sources must enable / disable operations before attaching or creating models

dataSource.operations()

List the enabled and disabled operations.

console.log(oracle.operations());

Output:

{
  find: {
    remoteEnabled: true,
    accepts: [...],
    returns: [...]
    enabled: true
  },
  save: {
    remoteEnabled: true,
    prototype: true,
    accepts: [...],
    returns: [...],
    enabled: true
  },
  ...
}

Connectors

Create a data source with a specific connector. See available connectors for specific connector documentation.

var memory = asteroid.createDataSource({
  connector: asteroid.Memory
});

Available Connectors

• Oracle
• In Memory
• TODO - REST
• TODO - MySQL
• TODO - SQLite3
• TODO - Postgres
• TODO - Redis
• TODO - MongoDB
• TODO - CouchDB
• TODO - Firebird

Installing Connectors

Include the connector in your package.json dependencies and run npm install.

{
  "dependencies": {
    "asteroid-oracle": "latest"
  }
}

GeoPoint

Embed a latitude / longitude point in a Model.

var CoffeeShop = asteroid.createModel('coffee-shop', {
  location: 'GeoPoint'
});

Asteroid Model's with a GeoPoint property and an attached DataSource may be queried using geo spatial filters and sorting.

Find the 3 nearest coffee shops.

CoffeeShop.attach(oracle);
var here = new GeoPoint({lat: 10.32424, long: 5.84978});
CoffeeShop.all({where: {location: {near: here}}}, function(err, nearbyShops) {
  console.info(nearbyShops); // [CoffeeShop, ...]
});

geoPoint.distanceTo(geoPoint, options)

Get the distance to another GeoPoint.

var here = new GeoPoint({lat: 10, long: 10});
var there = new GeoPoint({lat: 5, long: 5});
console.log(here.distanceTo(there, {type: 'miles'})); // 438

GeoPoint.distanceBetween(a, b, options)

Get the distance between two points.

GeoPoint.distanceBetween(here, there, {type: 'miles'}) // 438

Distance Types

• miles
• radians
• kilometers

geoPoint.lat

The latitude point in degrees. Range: -90 to 90.

geoPoint.long

The longitude point in degrees. Range: -180 to 180.

Asteroid Types

Various APIs in Asteroid accept type descriptions (eg. remote methods, asteroid.createModel()). The following is a list of supported types.

• null - JSON null
• Boolean - JSON boolean
• Number - JSON number
• String - JSON string
• Object - JSON object
• Array - JSON array
• Date - a JavaScript date object
• Buffer - a node.js Buffer object
• GeoPoint - an asteroid GeoPoint object.

REST Router

Expose models over rest using the asteroid.rest router.

app.use(asteroid.rest());

REST Documentation

View generated REST documentation by visiting: http://localhost:3000/_docs.

SocketIO Middleware Not Available

Coming Soon - Expose models over socket.io using the asteroid.sio() middleware.

app.use(asteroid.sio);