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asteroid

v0.7.0

Install

slnode install asteroid -g

Server API

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:

app.model(Model)

Expose a Model to remote clients.

var memory = asteroid.createDataSource({connector: 'memory'});
var Color = memory.defineModel({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.name); // color
});

Model

An Asteroid Model is a vanilla JavaScript class constructor with an attached set of properties and settings. A Model instance is created by passing a data object containing properties to the Model constructor.

var Color = asteroid.createModel({name: 'string'});
var red = new Color({name: 'red'});

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().

Settings

Some DataSources may support additional Model settings.

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: '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);
    }
  });
}

Expose the static model method to clients as a remote method.

asteroid.remoteMethod(
  User,
  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, 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(Model, fn, [options]);

Expose a remote method.

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

asteroid.remoteMethod(
  Product,
  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.

Hooks

Run a function before or after a model method is called.

User.before('save', function(user, next) {
  console.log('about to save', user);
  
  next();
});

Prevent the method from being called by passing an error to next().

User.before('delete', function(user, next) {
  // prevent all delete calls
  next(new Error('deleting is disabled'));
});

Remote Hooks

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

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

Context

Remote hooks are provided with a Context ctx that contains raw access to the transport specific objects. The ctx object also has a set of consistent apis that are consistent across transports.

ctx.me

The id of the user calling the method remotely. Note: this is undefined if a user is not logged in.

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

Model.availableHooks()

Return a list of available hooks.

console.log(User.availableHooks()); // ['save', ...]

Shared Methods

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

Model.availableMethods()

Returns the currently available api of a model as well as descriptions of any modified behavior or methods from attached data sources.

User.attachTo(oracle);
console.log(User.availableMethods());

Output:

{
  'User.all': {
    accepts: [{arg: 'filter', type: 'object', description: '...'}],
    returns: [{arg: 'users', type: ['User']}]
  },
  'User.find': {
    accepts: [{arg: 'id', type: 'any'}],
    returns: [{arg: 'items', type: 'User'}]
  },
  ...
}

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, options, settings)

Define a model and attach it to a DataSource.

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

dataSource.discover(options, fn)

Discover an object containing properties and settings for an existing data source.

oracle.discover({owner: 'MYORG'}, function(err, tables) {
  var productSchema = tables.PRODUCTS;
  var ProductModel = oracle.createModel('product', productSchema.properties, productSchema.settings);
});

dataSource.discoverSync(options)

Synchronously discover an object containing properties and settings for an existing data source tables or collections.

var tables = oracle.discover({owner: 'MYORG'});
var productSchema = tables.PRODUCTS;
var ProductModel = oracle.createModel('product', productSchema.properties, productSchema.settings);

dataSource.discoverModels(options, fn)

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

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

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

dataSource.discoverModelsSync(options)

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

var models = oracle.discoverModels({owner: 'MYORG'});
var ProductModel = models.Product;

dataSource.enable(operation)

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

// enable an operation
twitter.enable('find');

// enable remote access
twitter.enableRemote('find')

Notes:

  • only enabled operations will be added to attached models
  • data sources must enable / disable operations before attaching or creating models

dataSource.disable(operation)

Disable 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: '...',
  ...
});

// disable an operation completely
oracle.disable('destroyAll');

// 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: {
    allowRemote: 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: require('asteroid-memory')
});

Available Connectors

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);