DEPRECATED - please use motion-resource

Maglev

Faster, smoother iOS development. Pushing RubyMotion as hard as we can.

It's a Rails pun.

Still baking.

Models

Connect your models to your backend insanely fast.

Imagine http://thiswebsite.com/users/1.json returns something like:

{
    "id": "123",
    "name": "Clay",
    "posts": [{
        "id": "321",
        "name": "My First Post",
        "body": "Maglev is super neat"
    }]
}

We can define our models like this:

class User < Maglev::Model
  remote_attributes :id, :name

  has_many :posts

  collection_path '/users'
  member_path '/users/:id'
end

class Post < Maglev::Model
  remote_attributes :id, :name, :body

  belongs_to :user
end

Hook up our API like this:

Maglev::API.setup do
  root 'http://thiswebsite.com'
end

And grab all of our objects with nifty methods:

User.find(1) do |user|
  p user.posts.first.body
  # => Maglev is super neat
end

What about /users.json? It returns a structure like this:

{
    "users": [{
        "id": "123",
        "name": "Clay",
        "posts": [...]
    }]
}

User.find_all do |users| works out of the box.

Nested Collections

It is possible to do nested collections like this:

class Event < Maglev::Model
  remote_attributes :id, :name

  has_many :photos,
    collection_path: "/events/:id/photos",
    member_path: "/events/:event_id/photos/:id"

  def event_id
    self.id
  end
end

class Photo < Maglev::Model
  remote_attributes :id, :event_id, :url
  belongs_to :event
end

event = Event.new(...)

event.photos.find_all do |photos|
end

event.photos.find(13) do |photo|
end

Handeling Irregular Structure

Most JSON APIs return keys that don't always correspond to resource names. Maglev handles these flawlessly with the json_path property on most resources:

class User < Maglev::Model
  remote_attribute :city, json_path: "address.city"

  has_many :posts, json_path: "data"

  collection_path '/users', json_path: "members"
end

Thus, our /users would return something like:

{
    "members": [{
        "id": "123",
        "name": "Clay",
        "address": {
            "city": "San Francisco",
            "state": "CA"
        }
        "data": [...]
    }]
}

Notice how User#city is a nested resource inside the JSON; you can dig through the JSON with the value-path syntax.

Support Classes

The Maglev::Support module contains many wrappers and shortcuts that you could find useful in your project.

Transformer

A wrapper for NSValueTransformer:

# Creates a non-reversable NSValueTransformer
string_to_color = Maglev::Support::Transformer.to(NSString) do |value|
  UIColor.send("#{value.downcase}Color")
end

# Creates a reversable NSValueTransformer
bidirectional = Maglev::Suport::Transformer.to(NSString) do |value, reversed_value|
  if reversed_value
    get_string_for_color(reversed_value)
  else
    UIColor.send("#{value.downcase}Color")
  end
end

Examples

Please check the examples