transpose

Transpose

Simple object transpositions using hash map of attributes. Particularly useful when working with remote apis, and mapping from a remote structure, to a localized structure.

Example

You want to map a remote post model with mostly camel cased method names, to a local active record model.

class RemotePost < ::OpenStruct
  include ::Transpose::Transposable

  transposer "Post", {
    :Id => :remote_id,
    :Title => :title,
  }
end

And back again

class Post < ::ActiveRecord::Base
  include ::Transpose::Transposable

  transposer "RemotePost", {
    :remote_id => :Id,
    :title => :Title
  }
end

So you do

remote = ::RemotePost.new(:Id => '1234', :Title => "Nocturne In e Flat Op 9 No.2" )
local = remote.transpose(Post).save
#=> #<Post id="1234", title="Nocturne In e Flat Op 9 No.2">

Transposing already initialized instances

Supports passing an instance as well via transpose_instance

post = Post.new(:title => "prebuilt title")
remote_post = ::RemotePost.new(:Id => 1234)
remote_post.transpose_instance(post)
#=> #<Post id="1234", title="prebuilt title">

Roadmap

1. Implementing a good solution for working with external api gems, when classes have already been defined. I.E. abstracting injecting the transposer into remote model.

2. Maybe support for getter and setter value strategies, i.e. right now you cant map an object to a hash, since it sets/gets via send. However, Im not sure that should be a concern of this gem, as that would likely kill much of the simplicity which Id like to keep.

3. Maybe coercion of attributes via passing lambda as value

Installation

Add this line to your application's Gemfile:

gem 'transpose'

And then execute:

$ bundle

Or install it yourself as:

$ gem install transpose

Usage

TODO: Write usage instructions here

Contributing

1. Fork it ( https://github.com/[my-github-username]/transpose/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request