StructureMapper

Structure mapper is a generic mapper of nested data structures (Hash, Array, ...) to ruby objects using very simple but powerful syntax. Unlike other mappers that are tightly coupled with persistence (ActiceRecord, Mongomapper), StructureMapper does only one thing, but does it well.

Installation

Add this line to your application's Gemfile:

gem 'structure_mapper'

And then execute:

$ bundle

Or install it yourself as:

$ gem install structure_mapper

Usage

require 'structure_mapper'

class MappedObject

  include StructureMapper::Hash

  attribute test: String
end

mapped=MappedObject.from_structure({'test' => 'some value'})
mapped.test       # 'some value'
mapped.to_structure  # {'test' => 'some value'}

Example for Parsing JSON and Mapping to Objects

require 'json'
require 'structure_mapper'
require 'pp'

data = '''
{
  "name": "rails",
  "downloads": 32904409,
  "version": "4.0.3",
  "version_downloads": 154351,
  "platform": "ruby",
  "authors": "David Heinemeier Hansson",
  "info": "Ruby on Rails is a full-stack web framework optimized for programmer happiness and sustainable productivity. It encourages beautiful code by favoring convention over configuration.",
  "licenses": [
    "MIT"
  ],
  "project_uri": "http://rubygems.org/gems/rails",
  "gem_uri": "http://rubygems.org/gems/rails-4.0.3.gem",
  "homepage_uri": "http://www.rubyonrails.org",
  "wiki_uri": "http://wiki.rubyonrails.org",
  "documentation_uri": "http://api.rubyonrails.org",
  "mailing_list_uri": "http://groups.google.com/group/rubyonrails-talk",
  "source_code_uri": "http://github.com/rails/rails",
  "bug_tracker_uri": "http://github.com/rails/rails/issues",
  "dependencies": {
    "development": [],
    "runtime": [
      {
        "name": "actionmailer",
        "requirements": "= 4.0.3"
      },
      {
        "name": "actionpack",
        "requirements": "= 4.0.3"
      },
      {
        "name": "activerecord",
        "requirements": "= 4.0.3"
      },
      {
        "name": "activesupport",
        "requirements": "= 4.0.3"
      },
      {
        "name": "bundler",
        "requirements": "< 2.0, >= 1.3.0"
      },
      {
        "name": "railties",
        "requirements": "= 4.0.3"
      },
      {
        "name": "sprockets-rails",
        "requirements": "~> 2.0.0"
      }
    ]
  }

}
'''

class Dependency
  include StructureMapper::Hash
  attribute name: String
  attribute requirements: String
end

class RubyGemInfo
  include StructureMapper::Hash
  attribute name: String
  attribute downloads: Fixnum
  attribute version: String
  attribute version_downloads: Fixnum
  attribute platform: String
  attribute authors: String
  attribute info: String
  attribute licenses: []
  attribute project_uri: String
  attribute gem_uri: String
  attribute homepage_uri: String
  attribute wiki_uri: String
  attribute documentation_uri: String
  attribute mailing_list_uri: String
  attribute source_code_uri: String
  attribute bug_tracker_uri: String
  attribute dependencies: {String => [Dependency]}
end

info=RubyGemInfo.from_structure(JSON.parse data)

Contributing

1. Fork it ( http://github.com//structure_mapper/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 new Pull Request