Add counter cache for article followers

Victor Costa
1 parent d0472735
Showing 4 changed files with 35 additions and 12 deletions Show diff stats
app/models/article_follower.rb
db/migrate/20150909091347_add_followers_count_to_article.rb
test/fixtures/article_followers.yml
test/unit/article_test.rb
 class ArticleFollower < ActiveRecord::Base
+
   attr_accessible :article_id, :person_id, :since
-  belongs_to :article
+  belongs_to :article, :counter_cache => :followers_count
   belongs_to :person
+
 end
@@ -0,0 +1,15 @@
+class AddFollowersCountToArticle < ActiveRecord::Migration
+
+  def self.up
+    add_column :articles, :followers_count, :integer, :default => 0
+    add_column :article_versions, :followers_count, :integer
+
+    execute "update articles set followers_count = (select count(*) from article_followers where article_followers.article_id = articles.id)"
+  end
+
+  def self.down
+    remove_column :article_versions, :followers_count
+    remove_column :articles, :followers_count
+  end
+
+end
@@ -1,11 +0,0 @@
-# Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/Fixtures.html
-
-one:
-  person_id: 1
-  article_id: 1
-  since: 2015-06-16 17:02:01
-
-two:
-  person_id: 1
-  article_id: 1
-  since: 2015-06-16 17:02:01
@@ -2167,4 +2167,21 @@ class ArticleTest &lt; ActiveSupport::TestCase
     article.destroy
   end
  
+  should "increment followers count when a person follow an article" do
+    a = fast_create(Article)
+    p = fast_create(Person)
+    assert_difference "a.reload.followers_count" do
+      a.person_followers << p
+    end
+  end
+
+  should "decrement followers count when a person unfollow an article" do
+    p = fast_create(Person)
+    a = fast_create(Article, :profile_id => p)
+    a.person_followers << p
+    assert_difference "a.reload.followers_count", -1 do
+      a.person_followers.destroy_all
+    end
+  end
+
 end
1	1	class ArticleFollower < ActiveRecord::Base
	2	+
2	3	attr_accessible :article_id, :person_id, :since
3		- belongs_to :article
	4	+ belongs_to :article, :counter_cache => :followers_count
4	5	belongs_to :person
	6	+
5	7	end
...	...
...	...	@@ -0,0 +1,15 @@
	1	+class AddFollowersCountToArticle < ActiveRecord::Migration
	2	+
	3	+ def self.up
	4	+ add_column :articles, :followers_count, :integer, :default => 0
	5	+ add_column :article_versions, :followers_count, :integer
	6	+
	7	+ execute "update articles set followers_count = (select count(*) from article_followers where article_followers.article_id = articles.id)"
	8	+ end
	9	+
	10	+ def self.down
	11	+ remove_column :article_versions, :followers_count
	12	+ remove_column :articles, :followers_count
	13	+ end
	14	+
	15	+end
...	...
...	...	@@ -1,11 +0,0 @@
1		-# Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/Fixtures.html
2		-
3		-one:
4		- person_id: 1
5		- article_id: 1
6		- since: 2015-06-16 17:02:01
7		-
8		-two:
9		- person_id: 1
10		- article_id: 1
11		- since: 2015-06-16 17:02:01
...	...	@@ -2167,4 +2167,21 @@ class ArticleTest < ActiveSupport::TestCase
2167	2167	article.destroy
2168	2168	end
2169	2169
	2170	+ should "increment followers count when a person follow an article" do
	2171	+ a = fast_create(Article)
	2172	+ p = fast_create(Person)
	2173	+ assert_difference "a.reload.followers_count" do
	2174	+ a.person_followers << p
	2175	+ end
	2176	+ end
	2177	+
	2178	+ should "decrement followers count when a person unfollow an article" do
	2179	+ p = fast_create(Person)
	2180	+ a = fast_create(Article, :profile_id => p)
	2181	+ a.person_followers << p
	2182	+ assert_difference "a.reload.followers_count", -1 do
	2183	+ a.person_followers.destroy_all
	2184	+ end
	2185	+ end
	2186	+
2170	2187	end
...	...