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# ownership. Elasticsearch B.V. licenses this file to you under
# the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#	http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

module Elasticsearch
  module API
    module Indices
      module Actions

        # Return the mapping definition for specific field (or fields)
        #
        # @example Get mapping for a specific field across all indices
        #
        #     client.indices.get_field_mapping field: 'foo'
        #
        # @example Get mapping for a specific field in an index
        #
        #     client.indices.get_field_mapping index: 'foo', field: 'bar'
        #
        # @example Get mappings for multiple fields in an index
        #
        #     client.indices.get_field_mapping index: 'foo', field: ['bar', 'bam']
        #
        # @option arguments [List] :index A comma-separated list of index names
        # @option arguments [List] :type A comma-separated list of document types
        # @option arguments [List] :fields A comma-separated list of fields (*Required*)
        # @option arguments [Boolean] :include_type_name Whether a type should be returned in the body of the mappings.
        # @option arguments [Boolean] :include_defaults Whether the default mapping values should be returned as well
        # @option arguments [Boolean] :ignore_unavailable Whether specified concrete indices should be ignored when unavailable (missing or closed)
        # @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, none, all)
        # @option arguments [Boolean] :local Return local information, do not retrieve the state from master node (default: false)
        #
        # @see http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/indices-get-field-mapping.html
        #
        def get_field_mapping(arguments={})
          arguments = arguments.clone
          fields = arguments.delete(:field) || arguments.delete(:fields)
          raise ArgumentError, "Required argument 'field' missing" unless fields
          method = HTTP_GET
          path   = Utils.__pathify(
                     Utils.__listify(arguments[:index]),
                     '_mapping',
                     Utils.__listify(arguments[:type]),
                     'field',
                     Utils.__listify(fields)
                   )
          params = Utils.__validate_and_extract_params arguments, ParamsRegistry.get(__method__)
          body   = nil

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

        # Register this action with its valid params when the module is loaded.
        #
        # @since 6.1.1
        ParamsRegistry.register(:get_field_mapping, [
            :include_type_name,
            :include_defaults,
            :ignore_unavailable,
            :allow_no_indices,
            :expand_wildcards,
            :local ].freeze)
      end
    end
  end
end