module Elasticsearch
  module API
    module Indices
      module Actions

        # Get information about a specific alias.
        #
        # @example Return all indices an alias points to
        #
        #     client.indices.get_alias name: '2013'
        #
        # @example Return all indices matching a wildcard pattern an alias points to
        #
        #     client.indices.get_alias index: 'log*', name: '2013'
        #
        # @option arguments [List] :index A comma-separated list of index names to filter aliases
        # @option arguments [List] :name A comma-separated list of alias names to return (*Required*)
        # @option arguments [Boolean] :allow_no_indices Whether to ignore if a wildcard indices expression resolves into
        #                                               no concrete indices. (This includes `_all` string or when no
        #                                               indices have been specified)
        # @option arguments [String] :expand_wildcards Whether to expand wildcard expression to concrete indices that
        #                                              are open, closed or both. (options: open, closed)
        # @option arguments [String] :ignore_indices When performed on multiple indices, allows to ignore
        #                                            `missing` ones (options: none, missing) @until 1.0
        # @option arguments [Boolean] :ignore_unavailable Whether specified concrete indices should be ignored when
        #                                                 unavailable (missing, closed, etc)
        #
        # @see http://www.elasticsearch.org/guide/reference/api/admin-indices-aliases/
        #
        def get_alias(arguments={})
          raise ArgumentError, "Required argument 'name' missing" unless arguments[:name]
          valid_params = [
            :ignore_indices,
            :ignore_unavailable,
            :allow_no_indices,
            :expand_wildcards
          ]

          method = 'GET'
          path   = Utils.__pathify Utils.__listify(arguments[:index]), '_alias', Utils.__escape(arguments[:name])

          params = Utils.__validate_and_extract_params arguments, valid_params
          body   = nil

          perform_request(method, path, params, body).body
        end
      end
    end
  end
end