```ruby
require 'rest-client'
require 'json'

module Polr
  API_VERSION = 'v2'

  Error = Class.new StandardError

  module Api
    def self.api_url path = nil
      %Q(#{Polr.configuration.api_url}/api/#{API_VERSION}/action/#{path})
    end

    def self.api_key
      Polr.configuration.api_key
    end

    def self.process
      JSON.parse yield
    rescue Errno::ECONNREFUSED, Errno::EHOSTUNREACH => e # API unreachable
      raise Polr::Error.new 'Polr API is unreachable'
    rescue RestClient::Exception => e # HTTP status error
      result = (JSON.parse(e.response) rescue {})
      raise Polr::Error.new(result['error'] || 'undefined error')
    rescue JSON::ParserError => e # JSON error
      raise Polr::Error.new e.message
    end

    def self.request path, params
      RestClient.get( Api::api_url(path.to_s), { params: params.merge(key: Api::api_key, response_type: :json), content_type: :json, accept: :json, timeout: 10 } )
    end
  end

  # Actions to use

  def self.shorten url, **options
    Api::process { Api::request(:shorten, { url: url }.merge(options)) }
  end

  def self.lookup url_ending, **options
    Api::process { Api::request(:lookup, { url_ending: url_ending }.merge(options)) }
  end
end
```

Add indifferent access to hash response
user
```ruby
require 'rest-client'
require 'json'

module Polr
  API_VERSION = 'v2'

  Error = Class.new StandardError

  module Api
    def self.api_url path = nil
      %Q(#{Polr.configuration.api_url}/api/#{API_VERSION}/action/#{path})
    end

    def self.api_key
      Polr.configuration.api_key
    end

    def self.process
      JSON.parse(yield).with_indifferent_access
    rescue Errno::ECONNREFUSED, Errno::EHOSTUNREACH => e # API unreachable
      raise Polr::Error.new 'Polr API is unreachable'
    rescue RestClient::Exception => e # HTTP status error
      result = (JSON.parse(e.response) rescue {})
      raise Polr::Error.new(result['error'] || 'undefined error')
    rescue JSON::ParserError => e # JSON error
      raise Polr::Error.new e.message
    end

    def self.request path, params
      RestClient.get( Api::api_url(path.to_s), { params: params.merge(key: Api::api_key, response_type: :json), content_type: :json, accept: :json, timeout: 10 } )
    end
  end

  # Actions to use

  def self.shorten url, **options
    Api::process { Api::request(:shorten, { url: url }.merge(options)) }
  end

  def self.lookup url_ending, **options
    Api::process { Api::request(:lookup, { url_ending: url_ending }.merge(options)) }
  end
end
```
assistant