From 2cd439d279e6e169b47cfb18fa7dfe0e485cc5e2 Mon Sep 17 00:00:00 2001
From: Bryan Larsen <bryan@larsen.st>
Date: Fri, 19 Feb 2010 15:39:31 -0500
Subject: [PATCH] granting-write-access-to-others

It's not enough just to allow others to view your projects, you need to allow some people to make changes, too. The goal of this part of the tutorial is to add a "Contributor" checkbox next to each person in the side-bar.

Implementing this is left as an exercise for the reader. The steps are:

1. Add a boolean `contributor` field to the `ProjectMembership` model.
2. Modify the permissions of stories and tasks so that users with `contributor=true` on their project membership have update permission for the project.
3. Use the `<editor>` tag to create an ajax editor for the `contributor` field in the ProjectMembership card.

That's all the hints we're going to give you for this one -- good luck!

Ok, one more hint, here's some associations that might be handy in the Project model:

    has_many :contributor_memberships, :class_name => "ProjectMembership", :scope => :contributor
    has_many :contributors, :through => :contributor_memberships, :source => :user
{: .ruby}

And a helper method that might come in handy when implementing your permission methods:

    def accepts_changes_from?(user)
       user.administrator? || user == owner || user.in?(contributors)
    end
{: .ruby}
---
 app/models/project.rb                             | 10 +++++++++-
 app/models/project_membership.rb                  |  1 +
 app/views/taglibs/application.dryml               | 12 +++++++++++-
 db/migrate/20110419140701_projcet_contributors.rb |  9 +++++++++
 db/schema.rb                                      |  3 ++-
 5 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 db/migrate/20110419140701_projcet_contributors.rb

diff --git a/app/models/project.rb b/app/models/project.rb
index e0a51fa..23679fa 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -16,6 +16,14 @@ class Project < ActiveRecord::Base
 
   belongs_to :owner, :class_name => "User", :creator => true
 
+  has_many :contributor_memberships, :class_name => "ProjectMembership", :scope => :contributor
+  has_many :contributors, :through => :contributor_memberships, :source => :user
+
+  # permission helper
+  def accepts_changes_from?(user)
+    user.administrator? || user == owner || user.in?(contributors)
+  end
+  
   # --- Permissions --- #
 
   def create_permitted?
@@ -23,7 +31,7 @@ def create_permitted?
   end
 
   def update_permitted?
-    acting_user.administrator? || (owner_is?(acting_user) && !owner_changed?)
+    accepts_changes_from?(acting_user) && !owner_changed?
   end
 
   def destroy_permitted?
diff --git a/app/models/project_membership.rb b/app/models/project_membership.rb
index b7cc12e..33c2285 100644
--- a/app/models/project_membership.rb
+++ b/app/models/project_membership.rb
@@ -3,6 +3,7 @@ class ProjectMembership < ActiveRecord::Base
   hobo_model # Don't put anything above this
 
   fields do
+    contributor :boolean, :default => false
     timestamps
   end
 
diff --git a/app/views/taglibs/application.dryml b/app/views/taglibs/application.dryml
index e2b8215..2e24802 100644
--- a/app/views/taglibs/application.dryml
+++ b/app/views/taglibs/application.dryml
@@ -22,4 +22,14 @@
   <old-form merge>
     <field-list: fields="description, users"/>
   </old-form>
-</extend>
\ No newline at end of file
+</extend>
+
+<extend tag="card" for="ProjectMembership">
+  <old-card merge>
+    <body:>
+      <span>Contributor?</span>
+      <editor:contributor/>
+    </body:>
+  </old-card>
+</extend>
+
diff --git a/db/migrate/20110419140701_projcet_contributors.rb b/db/migrate/20110419140701_projcet_contributors.rb
new file mode 100644
index 0000000..99f3e9e
--- /dev/null
+++ b/db/migrate/20110419140701_projcet_contributors.rb
@@ -0,0 +1,9 @@
+class ProjcetContributors < ActiveRecord::Migration
+  def self.up
+    add_column :project_memberships, :contributor, :boolean, :default => false
+  end
+
+  def self.down
+    remove_column :project_memberships, :contributor
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 4fe0302..ef6c3ee 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,13 +11,14 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20110419132125) do
+ActiveRecord::Schema.define(:version => 20110419140701) do
 
   create_table "project_memberships", :force => true do |t|
     t.datetime "created_at"
     t.datetime "updated_at"
     t.integer  "project_id"
     t.integer  "user_id"
+    t.boolean  "contributor", :default => false
   end
 
   add_index "project_memberships", ["project_id"], :name => "index_project_memberships_on_project_id"