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# license agreements. See the NOTICE file distributed with
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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.

# frozen_string_literal: true

module ElasticAPM
  # @api private
  module Spies
    # @api private
    class HTTPSpy
      TYPE = 'ext'
      SUBTYPE = 'http_rb'
      def install
        ::HTTP::Client.class_eval do
          alias perform_without_apm perform

          def perform(req, options)
            unless (transaction = ElasticAPM.current_transaction)
              return perform_without_apm(req, options)
            end

            method = req.verb.to_s.upcase
            host = req.uri.host

            destination =
              ElasticAPM::Span::Context::Destination.from_uri(req.uri)
            context = ElasticAPM::Span::Context.new(
              http: { url: req.uri, method: method },
              destination: destination
            )

            name = "#{method} #{host}"

            ElasticAPM.with_span(
              name,
              TYPE,
              subtype: SUBTYPE,
              action: method,
              context: context
            ) do |span|
              trace_context = span&.trace_context || transaction.trace_context
              trace_context.apply_headers { |key, value| req[key] = value }

              result = perform_without_apm(req, options)

              if (http = span&.context&.http)
                http.status_code = result.status.to_s
              end

              result
            end
          end
        end
      end
    end

    register 'HTTP', 'http', HTTPSpy.new
  end
end