add reindex_immediately option (default: true), to suppress automatic…

… reindexing

README.md

@@ -243,6 +243,7 @@ Additional indexing/query options can be used as parameters to `fulltext_search_
     * When set to a string, the string is evaluated within the document's instance.
     * When set to a proc, the proc is called, and the document is given to the proc as the first arg.
     * When set to any other type of object, the document's index will not be updated.
+* `reindex_immediately`: whether models will be reindexed automatically upon saves or updates. Defaults to true. When set to false, the class-level `update_ngram_index` method can be called to perform reindexing.
 
 Array filters
 -------------

lib/mongoid_fulltext.rb

@@ -32,6 +32,7 @@ def fulltext_search_in(*args)
         :index_short_prefixes => false,
         :max_candidate_set_size => 1000,
         :remove_accents => true,
+        :reindex_immediately => true,
         :stop_words => Hash[['i', 'a', 's', 't', 'me', 'my', 'we', 'he', 'it', 'am', 'is', 'be', 'do', 'an', 'if', 
                              'or', 'as', 'of', 'at', 'by', 'to', 'up', 'in', 'on', 'no', 'so', 'our', 'you', 'him', 
                              'his', 'she', 'her', 'its', 'who', 'are', 'was', 'has', 'had', 'did', 'the', 'and', 
@@ -54,7 +55,7 @@ def fulltext_search_in(*args)
       config[:word_separators] = Hash[config[:word_separators].split('').map{ |ch| [ch,ch] }]
       self.mongoid_fulltext_config[index_name] = config
 
-      before_save :update_ngram_index
+      before_save(:update_ngram_index) if config[:reindex_immediately]
       before_destroy :remove_from_ngram_index
     end
 

spec/models/delayed_artwork.rb

@@ -0,0 +1,8 @@
+class DelayedArtwork
+  include Mongoid::Document
+  include Mongoid::FullTextSearch
+
+  field :title
+  fulltext_search_in :title, :reindex_immediately => false
+
+end

spec/mongoid/fulltext_spec.rb

@@ -669,5 +669,16 @@ module Mongoid
       end
 
     end
+
+    context "batched reindexing" do
+      let!(:flowers1) { DelayedArtwork.create(:title => 'Flowers 1') }
+
+      it "should not rebuild index until explicitly invoked" do
+        DelayedArtwork.fulltext_search("flowers").length.should == 0
+        DelayedArtwork.update_ngram_index
+        DelayedArtwork.fulltext_search("flowers").length.should == 1
+      end
+    end
+
   end
 end