[RAILS] Refactored and updated the instrumentation support to allow integration with Persistence::Model

When the instrumentation/lograge components are now used with the Persistence::Model models,
Rails log prints the relevant info:

    Article Search (174.8ms) {index: "articles-development", type: "article", body: {size: 50, from: 0, sort: {created_at: "desc"}, query: {filtered: {query: {query_string: {query: "foo*", default_operator: "AND"}}, filter: {bool: {must_not: {term: {deleted: true}}}}}} ...
      Rendered articles/index.html.erb within layouts/application (57.7ms)
      Rendered articles/_search_form.html.erb (1.2ms)
    Completed 200 OK in 861ms (Views: 623.9ms | Elasticsearch: 174.8ms)

Closes elastic#238

Author: karmi

elasticsearch-rails/lib/elasticsearch/rails/instrumentation/publishers.rb

@@ -9,22 +9,28 @@ module Publishers
         # @see http://api.rubyonrails.org/classes/ActiveSupport/Notifications.html
         #
         module SearchRequest
-          extend ActiveSupport::Concern
 
-          included do
-            alias_method_chain :execute!, :instrumentation
-          end
+          def self.included(base)
+            base.class_eval do
+              alias_method :execute_without_instrumentation!, :execute!
+
+              def execute!
+                execute_with_instrumentation!
+              end
 
-          # Wrap `Search#execute!` and perform instrumentation
-          #
-          def execute_with_instrumentation!
-            ActiveSupport::Notifications.instrument "search.elasticsearch",
-              name:   'Search',
-              klass:  (self.klass.is_a?(Elasticsearch::Model::Proxy::ClassMethodsProxy) ? self.klass.target.to_s : self.klass.to_s),
-              search: self.definition do
-              execute_without_instrumentation!
+              # Wrap `Search#execute!` and perform instrumentation
+              #
+              def execute_with_instrumentation!
+                ActiveSupport::Notifications.instrument "search.elasticsearch",
+                  name:   'Search',
+                  klass:  (self.klass.is_a?(Elasticsearch::Model::Proxy::ClassMethodsProxy) ? self.klass.target.to_s : self.klass.to_s),
+                  search: self.definition do
+                  execute_without_instrumentation!
+                end
+              end
             end
           end
+
         end
       end
     end

elasticsearch-rails/lib/elasticsearch/rails/instrumentation/railtie.rb

@@ -14,7 +14,11 @@ class Railtie < ::Rails::Railtie
 
           Elasticsearch::Model::Searching::SearchRequest.class_eval do
             include Elasticsearch::Rails::Instrumentation::Publishers::SearchRequest
-          end
+          end if defined?(Elasticsearch::Model::Searching::SearchRequest)
+
+          Elasticsearch::Persistence::Model::Find::SearchRequest.class_eval do
+            include Elasticsearch::Rails::Instrumentation::Publishers::SearchRequest
+          end if defined?(Elasticsearch::Persistence::Model::Find::SearchRequest)
 
           ActiveSupport.on_load(:action_controller) do
             include Elasticsearch::Rails::Instrumentation::ControllerRuntime

elasticsearch-rails/lib/elasticsearch/rails/lograge.rb

@@ -21,17 +21,21 @@ class Railtie < ::Rails::Railtie
           require 'elasticsearch/rails/instrumentation/log_subscriber'
           require 'elasticsearch/rails/instrumentation/controller_runtime'
 
-          config.lograge.custom_options = lambda do |event|
-            { es: event.payload[:elasticsearch_runtime].to_f.round(2) }
-          end
-
           Elasticsearch::Model::Searching::SearchRequest.class_eval do
             include Elasticsearch::Rails::Instrumentation::Publishers::SearchRequest
-          end
+          end if defined?(Elasticsearch::Model::Searching::SearchRequest)
+
+          Elasticsearch::Persistence::Model::Find::SearchRequest.class_eval do
+            include Elasticsearch::Rails::Instrumentation::Publishers::SearchRequest
+          end if defined?(Elasticsearch::Persistence::Model::Find::SearchRequest)
 
           ActiveSupport.on_load(:action_controller) do
             include Elasticsearch::Rails::Instrumentation::ControllerRuntime
           end
+
+          config.lograge.custom_options = lambda do |event|
+            { es: event.payload[:elasticsearch_runtime].to_f.round(2) }
+          end
         end
       end