[MODEL] Added Elasticsearch::Model::Callbacks module to automatically update the index by using model callbacks

The behaviour is opt-in -- you have to include the module so the callbacks are registered.

Example:

    class Article < ActiveRecord::Base
      include Elasticsearch::Model
      include Elasticsearch::Model::Callbacks
    end

    Article.create title: 'New Record'

       (0.3ms)  begin transaction
      SQL (0.3ms)  INSERT INTO "articles" ("created_at", "title", "updated_at") VALUES (?, ?, ?)  [["created_at", 2013-11-12 18:21:15 UTC], ["title", "New Record"], ["updated_at", 2013-11-12 18:21:15 UTC]]
       (0.1ms)  commit transaction

    2013-11-12 19:21:15 +0100: PUT http://localhost:9200/articles/article/4 [status:201, request:0.005s, query:n/a]
    2013-11-12 19:21:15 +0100: > {"id":4,"title":"New Record","published_at":null,"created_at":"2013-11-12T18:21:15Z","updated_at":"2013-11-12T18:21:15Z"}
    2013-11-12 19:21:15 +0100: < {"ok":true,"_index":"articles","_type":"article","_id":"4","_version":1}

    # => #<Article id: 4, title: "New Record", published_at: nil, created_at: "2013-11-12 18:21:15", updated_at: "2013-11-12 18:21:15">

Author: karmi

elasticsearch-model/lib/elasticsearch/model.rb

@@ -17,6 +17,7 @@
 require 'elasticsearch/model/naming'
 require 'elasticsearch/model/serializing'
 require 'elasticsearch/model/searching'
+require 'elasticsearch/model/callbacks'
 
 require 'elasticsearch/model/proxy'
 

elasticsearch-model/lib/elasticsearch/model/adapter.rb

@@ -24,6 +24,10 @@ def records_mixin
           adapter.const_get(:Records)
         end
 
+        def callbacks_mixin
+          adapter.const_get(:Callbacks)
+        end
+
         def adapter
           @adapter ||= begin
             self.class.adapters.find( lambda {[]} ) { |name, condition| condition.call(klass) }.first \

elasticsearch-model/lib/elasticsearch/model/adapters/active_record.rb

@@ -47,6 +47,16 @@ def order(*args)
           end
         end
 
+        module Callbacks
+          def self.included(base)
+            base.class_eval do
+              after_commit lambda { __elasticsearch__.index_document  },  on: [:create]
+              after_commit lambda { __elasticsearch__.update_document },  on: [:update]
+              after_commit lambda { __elasticsearch__.delete_document },  on: [:destroy]
+            end
+          end
+        end
+
       end
 
     end

elasticsearch-model/lib/elasticsearch/model/adapters/default.rb

@@ -12,6 +12,10 @@ def records
           end
         end
 
+        module Callbacks
+          # noop
+        end
+
       end
     end
   end

elasticsearch-model/lib/elasticsearch/model/adapters/mongoid.rb

@@ -35,6 +35,14 @@ def records
           end
         end
 
+        module Callbacks
+          def self.included(base)
+            base.after_create  { |document| document.__elasticsearch__.index_document  }
+            base.after_update  { |document| document.__elasticsearch__.update_document }
+            base.after_destroy { |document| document.__elasticsearch__.delete_document }
+          end
+        end
+
       end
 
     end

elasticsearch-model/lib/elasticsearch/model/callbacks.rb

@@ -0,0 +1,12 @@
+module Elasticsearch
+  module Model
+    module Callbacks
+
+      def self.included(base)
+        adapter = Adapter.from_class(base)
+        base.__send__ :include, adapter.callbacks_mixin
+      end
+
+    end
+  end
+end