adding ability to maintain a snapshot of multiple collections atomica…

…lly, bumping version to 1.0

README.md

@@ -3,8 +3,8 @@ Mongoid Collection Snapshot
 
 Easy maintenance of collections of processed data in MongoDB with the Mongoid ODM.
 
-Example:
---------
+Quick example:
+--------------
 
 Suppose that you have a Mongoid model called `Artwork`, stored
 in a MongoDB collection called `artworks` and the underlying documents 
@@ -78,3 +78,31 @@ method `build`, which populates the collection snapshot and any indexes you need
 By default, mongoid_collection_snapshot maintains the most recent two snapshots 
 computed any given time.
 
+Other features
+--------------
+
+You can maintain multiple collections atomically within the same snapshot by
+passing unique collection identifiers to ``collection_snaphot`` when you call it 
+in your build or query methods:
+
+    class ArtistStats
+      include Mongoid::CollectionSnapshot
+
+      def build
+        # ...
+        # define map/reduce for average and max aggregations
+	# ...
+	Artwork.collection.map_reduce(map_avg, reduce_avg, :out => collection_snapshot('average'))
+	Artwork.collection.map_reduce(map_max, reduce_max, :out => collection_snapshot('max'))
+      end
+
+      def average_price(artist)
+        doc = collection_snapshot('average').findOne({'_id.artist': artist})
+        doc['value']['sum']/doc['value']['count']
+      end
+
+      def max_price(artist)
+        doc = collection_snapshot('max').findOne({'_id.artist': artist})
+        doc['value']['max']
+      end
+    end	

VERSION

@@ -1 +1 @@
-0.0.1
+0.1.0

lib/mongoid_collection_snapshot.rb

@@ -15,7 +15,7 @@ module Mongoid::CollectionSnapshot
 
     before_save :build
     after_save :ensure_at_most_two_instances_exist
-    before_destroy :drop_snapshot_collection
+    before_destroy :drop_snapshot_collections
   end
 
   module ClassMethods
@@ -24,12 +24,18 @@ def latest
     end
   end
 
-  def collection_snapshot
-    Mongoid.master.collection("#{self.collection.name}.#{workspace_slug}")
+  def collection_snapshot(name=nil)
+    if name
+      Mongoid.master.collection("#{self.collection.name}.#{name}.#{workspace_slug}")
+    else
+      Mongoid.master.collection("#{self.collection.name}.#{workspace_slug}")
+    end
   end
 
-  def drop_snapshot_collection
-    collection_snapshot.drop
+  def drop_snapshot_collections
+    Mongoid.master.collections.each do |collection|
+      collection.drop if collection.name =~ /^#{self.collection.name}\.([^\.]+\.)?#{workspace_slug}$/
+    end
   end
 
   # Since we should always be using the latest instance of this class, this method is

mongoid_collection_snapshot.gemspec

@@ -4,14 +4,14 @@
 # -*- encoding: utf-8 -*-
 
 Gem::Specification.new do |s|
-  s.name = %q{mongoid_collection_snapshot}
-  s.version = "0.0.1"
+  s.name = "mongoid_collection_snapshot"
+  s.version = "0.1.0"
 
   s.required_rubygems_version = Gem::Requirement.new(">= 0") if s.respond_to? :required_rubygems_version=
   s.authors = ["Aaron Windsor"]
-  s.date = %q{2011-09-02}
-  s.description = %q{Easy maintenence of collections of processed data in MongoDB with the Mongoid ODM}
-  s.email = %q{aaron.windsor@gmail.com}
+  s.date = "2012-01-24"
+  s.description = "Easy maintenence of collections of processed data in MongoDB with the Mongoid ODM"
+  s.email = "aaron.windsor@gmail.com"
   s.extra_rdoc_files = [
     "LICENSE.txt",
     "README.md"
@@ -26,17 +26,19 @@ Gem::Specification.new do |s|
     "mongoid_collection_snapshot.gemspec",
     "spec/models/artwork.rb",
     "spec/models/average_artist_price.rb",
+    "spec/models/multi_collection_snapshot.rb",
     "spec/mongoid/collection_snapshot_spec.rb",
     "spec/spec_helper.rb"
   ]
-  s.homepage = %q{http://github.com/aaw/mongoid_collection_snapshot}
+  s.homepage = "http://github.com/aaw/mongoid_collection_snapshot"
   s.licenses = ["MIT"]
   s.require_paths = ["lib"]
-  s.rubygems_version = %q{1.6.2}
-  s.summary = %q{Easy maintenence of collections of processed data in MongoDB with the Mongoid ODM}
+  s.rubygems_version = "1.8.10"
+  s.summary = "Easy maintenence of collections of processed data in MongoDB with the Mongoid ODM"
   s.test_files = [
     "spec/models/artwork.rb",
     "spec/models/average_artist_price.rb",
+    "spec/models/multi_collection_snapshot.rb",
     "spec/mongoid/collection_snapshot_spec.rb",
     "spec/spec_helper.rb"
   ]

spec/models/multi_collection_snapshot.rb

@@ -0,0 +1,14 @@
+class MultiCollectionSnapshot
+  include Mongoid::CollectionSnapshot
+
+  def build
+    collection_snapshot('foo').insert({'name' => 'foo!'})
+    collection_snapshot('bar').insert({'name' => 'bar!'})
+    collection_snapshot('baz').insert({'name' => 'baz!'})
+  end
+
+  def get_names
+    ['foo', 'bar', 'baz'].map{ |x| collection_snapshot(x).find_one['name'] }.join('')
+  end
+
+end

spec/mongoid/collection_snapshot_spec.rb

@@ -3,7 +3,7 @@
 module Mongoid
   describe CollectionSnapshot do
 
-    context "creating a snapshot" do
+    context "creating a basic snapshot" do
 
       let!(:flowers)     { Artwork.create(:name => 'Flowers', :artist => 'Andy Warhol', :price => 3000000) }
       let!(:guns)        { Artwork.create(:name => 'Guns', :artist => 'Andy Warhol', :price => 1000000) }
@@ -12,11 +12,13 @@ module Mongoid
       it "returns nil if no snapshot has been created" do
         AverageArtistPrice.latest.should be_nil
       end
+
       it "runs the build method on creation" do
         snapshot = AverageArtistPrice.create
         snapshot.average_price('Andy Warhol').should == 2000000
         snapshot.average_price('Damien Hirst').should == 1500000
       end
+
       it "returns the most recent snapshot through the latest methods" do
         first = AverageArtistPrice.create
         first.should == AverageArtistPrice.latest
@@ -31,12 +33,47 @@ module Mongoid
         third = AverageArtistPrice.create
         AverageArtistPrice.latest.should == third        
       end
+
       it "should only maintain at most two of the latest snapshots to support its calculations" do
+        AverageArtistPrice.create
         10.times do
           AverageArtistPrice.create
-          AverageArtistPrice.count.should <= 2
+          AverageArtistPrice.count.should == 2
         end
       end
+
+    end
+
+    context "creating a snapshot containing multiple collections" do
+
+      it "populates several collections and allows them to be queried" do
+        MultiCollectionSnapshot.latest.should be_nil
+        10.times { MultiCollectionSnapshot.create }
+        MultiCollectionSnapshot.latest.get_names.should == "foo!bar!baz!"
+      end
+
+      it "safely cleans up all collections used by the snapshot" do
+        # Create some collections with names close to the snapshots we'll create
+        Mongoid.master["#{MultiCollectionSnapshot.collection.name}.do.not_delete"].insert({'a' => 1})
+        Mongoid.master["#{MultiCollectionSnapshot.collection.name}.snapshorty"].insert({'a' => 1})
+        Mongoid.master["#{MultiCollectionSnapshot.collection.name}.hello.1"].insert({'a' => 1})
+
+        MultiCollectionSnapshot.create
+        before_create = Mongoid.master.collections.map{ |c| c.name }
+        before_create.length.should > 0
+
+        sleep(1)
+        MultiCollectionSnapshot.create
+        after_create = Mongoid.master.collections.map{ |c| c.name }
+        collections_created = (after_create - before_create).sort
+        collections_created.length.should == 3
+
+        MultiCollectionSnapshot.latest.destroy
+        after_destroy = Mongoid.master.collections.map{ |c| c.name }
+        collections_destroyed = (after_create - after_destroy).sort
+        collections_created.should == collections_destroyed
+      end
+
     end
 
   end