YamlConvertor

Ruby gem that converts a YAML hash structure to a simple hash consisting of key:value only, and vice versa

a YAML hash structure could look like this:

{"fruit"=> {
    "lemon"=>"yellow", 
    "apple"=>{ "red_apples"=>"red" }
  }
}

The resulting simple key:value hash looks like this:

{"fruit.lemon"=>"yellow", "fruit.apple.red_apples"=>"red"}

This works the other way around, too: if you had the simple hash; you can reconstruct the YAML hash structure.

Installation

Add this line to your application's Gemfile:

    gem 'yaml_convertor'

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install yaml_convertor

Usage

There are two methods you can use:

• flattener converts the structured nested YAML hash to a simple key:value

YamlConvertor.flattener(yml_hash)

• builder rebuilds the simple hash to a nested YAML structure

YamlConvertor.builder(flat_hash)

Example

Let's assume we have a YAML file called file.yml:

en:
  errors:
    messages:
      not_locked: "was not locked"
      not_saved:
        other: "other error"
  devise:
    failure:
      already_authenticated: 'You are already signed in.'
    sessions:
      signed_in: 'Signed in successfully.'

We open this file using Psych (Ruby's YAML parser), and it will return a nested YAML hash structure

yml_hash = Psych.load_file('file.yml')

yml_hash looks like this:

{"en"=>{
  "errors"=>{
    "messages"=>{
      "not_locked"=>"was not locked", 
      "not_saved"=>{"other"=>"other error"}
    }
  }, 
  "devise"=>{
    "failure"=>{"already_authenticated"=>"You are already signed in."}, 
    "sessions"=>{"signed_in"=>"Signed in successfully."}}
  }
}

Now! If we use flattener:

flat_hash = YamlConvertor.flattener(yml_hash)

flat_hash will look like this:

{
  "en.errors.messages.not_locked"=>"was not locked", 
  "en.errors.messages.not_saved.other"=>"other error", 
  "en.devise.failure.already_authenticated"=>"You are already signed in.", 
  "en.devise.sessions.signed_in"=>"Signed in successfully."
}

Example 2

Now let's assume we have a flat hash and we want to rebuild it to a YAML file. Here's our flat_hash from our example above:

flat_hash = {"en.errors.messages.not_locked"=>"was not locked", "en.errors.messages.not_saved.other"=>"other error", "en.devise.failure.already_authenticated"=>"You are already signed in.", "en.devise.sessions.signed_in"=>"Signed in successfully."}
nested_hash = YamlConvertor.builder(flat_hash)

nested_hash is now:

{"en"=>{
  "errors"=>{
    "messages"=>{
      "not_locked"=>"was not locked", 
      "not_saved"=>{"other"=>"other error"}
    }
  }, 
  "devise"=>{
    "failure"=>{"already_authenticated"=>"You are already signed in."}, 
    "sessions"=>{"signed_in"=>"Signed in successfully."}}
  }
}

Dump it with Pysch..

Psych.dump(nested_hash)

The output will be:

---
en:
  errors:
    messages:
      not_locked: was not locked
      not_saved:
        other: other error
  devise:
    failure:
      already_authenticated: You are already signed in.
    sessions:
      signed_in: Signed in successfully.

Note

These methods only work properly if you have valid YAML structure. I didn't test that yet but I assume so!

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Added some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request