[CLIENT] Centralize header handling into one method

Author: estolfo

elasticsearch-transport/lib/elasticsearch/transport/transport/base.rb

@@ -401,6 +401,7 @@ def apply_headers(client, options)
           headers = options[:headers] || {}
           headers[CONTENT_TYPE_STR] = find_value(headers, CONTENT_TYPE_REGEX) || DEFAULT_CONTENT_TYPE
           headers[USER_AGENT_STR] = find_value(headers, USER_AGENT_REGEX) || user_agent_header(client)
+          client.headers[ACCEPT_ENCODING] = GZIP if use_compression?
           client.headers.merge!(headers)
         end
 

elasticsearch-transport/lib/elasticsearch/transport/transport/http/curb.rb

@@ -104,18 +104,6 @@ def host_unreachable_exceptions
 
           private
 
-          def apply_headers(client, options)
-            super
-
-            if use_compression?
-              if client.headers
-                client.headers[ACCEPT_ENCODING] = GZIP
-              else
-                client.headers = { ACCEPT_ENCODING => GZIP }
-              end
-            end
-          end
-
           def user_agent_header(client)
             @user_agent ||= begin
               meta = ["RUBY_VERSION: #{RUBY_VERSION}"]

elasticsearch-transport/lib/elasticsearch/transport/transport/http/faraday.rb

@@ -51,7 +51,6 @@ def perform_request(method, path, params={}, body=nil, headers=nil)
           # @return [Connections::Connection]
           #
           def __build_connection(host, options={}, block=nil)
-            options.merge!(headers: { accept_encoding: GZIP }) if use_compression?
             client = ::Faraday.new(__full_url(host), options, &block)
             apply_headers(client, options)
             Connections::Connection.new :host => host, :connection => client