fix legacy wiki front page behavior

test plan:
 - in a course with no pages (new course is best)
 * manually update the course object:
   * set default_view to 'wiki'
 * manually update the course's wiki object:
   * set front_page_url to nil
   * set has_no_front_page to true
 * navigate to the course home page
 - there should not be an error on the page

fixes CNVS-7744

Change-Id: I047db32d2fa7a376be994a1314c0e55a0cadffde
Reviewed-on: https://gerrit.instructure.com/23751
QA-Review: Hannah Bottalla <hannah@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jeremy Stanley <jeremy@instructure.com>
Product-Review: Bracken Mosbacker <bracken@instructure.com>

app/controllers/courses_controller.rb

@@ -1108,6 +1108,12 @@ class CoursesController < ApplicationController
 
       @course_home_view = (params[:view] == "feed" && 'feed') || @context.default_view || 'feed'
 
+      # make sure the wiki front page exists
+      if @course_home_view == 'wiki'
+        @context.wiki.check_has_front_page
+        @course_home_view = 'feed' if @context.wiki.front_page.nil?
+      end
+
       @contexts = [@context]
       case @course_home_view
       when "wiki"

app/controllers/wiki_pages_controller.rb

@@ -102,6 +102,10 @@ class WikiPagesController < ApplicationController
     initialize_wiki_page
 
     if @page.update_attributes(params[:wiki_page].merge(:user_id => @current_user.id))
+      unless @page.context.draft_state_enabled?
+        @page.set_as_front_page! if !@page.wiki.has_front_page? and @page.url == Wiki::DEFAULT_FRONT_PAGE_URL
+      end
+
       log_asset_access(@page, "wiki", @wiki, 'participate')
       generate_new_page_view
       @page.context_module_action(@current_user, @context, :contributed)

app/models/course.rb

@@ -1958,7 +1958,7 @@ class Course < ActiveRecord::Base
     end
 
     # be very explicit about draft state courses, but be liberal toward legacy courses
-    if self.root_account.enable_draft?
+    if self.draft_state_enabled?
       if migration.for_course_copy? && (source = migration.source_course || Course.find_by_id(migration.migration_settings[:source_course_id]))
         self.wiki.has_no_front_page = !!source.wiki.has_no_front_page
         self.wiki.front_page_url = source.wiki.front_page_url
@@ -1966,7 +1966,7 @@ class Course < ActiveRecord::Base
       end
     end
     front_page = self.wiki.front_page
-    self.wiki.unset_front_page! if front_page.nil? || (self.root_account.enable_draft? && front_page.new_record?)
+    self.wiki.unset_front_page! if front_page.nil? || (self.draft_state_enabled? && front_page.new_record?)
 
     syllabus_should_be_added = everything_selected || migration.copy_options[:syllabus_body] || migration.copy_options[:all_syllabus_body]
     if syllabus_should_be_added

app/models/wiki.rb

@@ -30,15 +30,17 @@ class Wiki < ActiveRecord::Base
   attr_accessible :title
 
   has_many :wiki_pages, :dependent => :destroy
-  before_create :default_front_page
+  before_save :set_has_no_front_page_default
   after_save :update_contexts
 
   DEFAULT_FRONT_PAGE_URL = 'front-page'
 
-  def default_front_page
-    has_no_front_page = front_page_url.nil? if has_no_front_page.nil?
+  def set_has_no_front_page_default
+    if self.has_no_front_page.nil? && self.id && context
+      self.has_no_front_page = true if context.draft_state_enabled?
+    end
   end
-  private :default_front_page
+  private :set_has_no_front_page_default
 
   def update_contexts
     self.context.try(:touch)
@@ -66,18 +68,26 @@ class Wiki < ActiveRecord::Base
 
   def check_has_front_page
     return unless self.has_no_front_page.nil?
-    self.has_no_front_page = !self.wiki_pages.where(:url => self.front_page_url || DEFAULT_FRONT_PAGE_URL).exists?
+
+    url = DEFAULT_FRONT_PAGE_URL
+    self.has_no_front_page = !self.wiki_pages.not_deleted.where(:url => url).exists?
+    self.front_page_url = url unless self.has_no_front_page
     self.save
   end
   
   def front_page
-    return nil unless has_front_page?
+    url = self.get_front_page_url
+    return nil if url.nil?
+
     # TODO i18n
     t :front_page_name, "Front Page"
-    url = self.get_front_page_url
-    page = self.wiki_pages.find_by_url(url)
+    # attempt to find the page and store it's url (if it is found)
+    page = self.wiki_pages.not_deleted.find_by_url(url)
+    self.set_front_page_url!(url) if self.has_no_front_page && page
+
+    # return an implicitly created page if a page could not be found
     unless page
-      page = self.wiki_pages.new(:title => "Front Page", :url => url)
+      page = self.wiki_pages.new(:title => url.titleize, :url => url)
       page.wiki = self
     end
     page
@@ -88,7 +98,7 @@ class Wiki < ActiveRecord::Base
   end
 
   def get_front_page_url
-    return nil unless self.has_front_page?
+    return nil unless self.has_front_page? || !context.draft_state_enabled?
     self.front_page_url || DEFAULT_FRONT_PAGE_URL
   end
 

app/models/wiki_page.rb

@@ -209,7 +209,8 @@ class WikiPage < ActiveRecord::Base
   end
 
   def is_front_page?
-    !self.deleted? && self.wiki.has_front_page? && self.url == self.wiki.get_front_page_url
+    return false if self.deleted?
+    self.url == self.wiki.get_front_page_url # wiki.get_front_page_url checks has_front_page? and context.draft_state_enabled?
   end
 
   def set_as_front_page!

app/views/courses/show.html.erb

@@ -200,9 +200,7 @@ $(document).ready(function() {
       <label for="edit_course_home_content_select"><strong><%= t('labels.set_layout', %{When people visit the course page, show them}) %></strong></label>
       <select name="course[default_view]" id="edit_course_home_content_select">
         <option value="feed" <%= 'selected' if @context.default_view == 'feed' %>><%= t('options.recent_activity_dashboard', %{the Recent Activity Dashboard}) %></option>
-        <% if @context.wiki.has_front_page? %>
-          <option value="wiki" <%= 'selected' if @context.default_view == 'wiki' %>><%= t('options.custom_page', %{a Page I'll Design Myself}) %></option>
-        <% end %>
+        <option value="wiki" <%= 'selected' if @context.default_view == 'wiki' %>><%= t('options.custom_page', %{a Page I'll Design Myself}) %></option>
         <option value="modules" <%= 'selected' if @context.default_view == 'modules' %>><%= t('options.modules', %{the Course Modules/Sections}) %></option>
         <option value="assignments" <%= 'selected' if @context.default_view == 'assignments' %>><%= t('options.assignments', %{the Assignment List}) %></option>
         <option value="syllabus" <%= 'selected' if @context.default_view == 'syllabus' %>><%= t('options.syllabus', %{the Assignments with Syllabus}) %></option>

app/views/wiki_pages/_wiki_right_side.html.erb

@@ -69,7 +69,7 @@
   <% if can_do(@page, @current_user, :update_content)%>
     <%= link_to ('<i class="icon-edit"></i>').html_safe + " " + t('links.edit_page', "Edit this Page"), "#edit", :class => "edit_link btn button-sidebar-wide" %>
   <% end %>
-  <% if can_do(@page, @current_user, :delete) && !@page.is_front_page? && !@page.deleted? %>
+  <% if can_do(@page, @current_user, :delete) && !@page.new_record? && !@page.is_front_page? && !@page.deleted? %>
     <%= link_to ('<i class="icon-trash"></i>').html_safe + " " + t('links.delete_page', "Delete this Page"), context_url(@context, :context_wiki_page_url, @page.url), :method => :delete, :confirm => t('delete_page_confirmation', 'Are you sure you want to delete this page? This cannot be undone!'), :class => "btn button-sidebar-wide" %>
   <% end %>
   <a href="<%= context_url(@context, :context_wiki_page_url, @page) %>" class="wiki_page_url" style="display: none;">&nbsp;</a>

db/migrate/20130828191910_fix_imported_wiki_front_pages.rb

@@ -0,0 +1,14 @@
+class FixImportedWikiFrontPages < ActiveRecord::Migration
+  tag :postdeploy
+
+  def self.up
+    DataFixup::FixImportedWikiFrontPages.send_later_if_production_enqueue_args(
+      :run,
+      :priority => Delayed::LOW_PRIORITY,
+      :max_attempts => 1
+    )
+  end
+
+  def self.down
+  end
+end

lib/data_fixup/fix_imported_wiki_front_pages.rb

@@ -0,0 +1,12 @@
+module DataFixup::FixImportedWikiFrontPages
+  # some Wiki objects are getting has_no_front_page set to true, even when there should be a front page
+  def self.potentially_broken_wikis
+    Wiki.where(:has_no_front_page => true)
+  end
+
+  def self.run
+    self.potentially_broken_wikis.find_in_batches do |wikis|
+      Wiki.where(:id => wikis).update_all(:has_no_front_page => nil)
+    end
+  end
+end

spec/apis/v1/pages_api_spec.rb

@@ -56,6 +56,7 @@ describe "Pages API", :type => :integration do
     @front_page = @wiki.front_page
     @front_page.workflow_state = 'active'
     @front_page.save!
+    @front_page.set_as_front_page!
     @hidden_page = @wiki.wiki_pages.create!(:title => "Hidden Page", :hide_from_students => true, :body => "Body of hidden page")
   end
 
@@ -270,12 +271,39 @@ describe "Pages API", :type => :integration do
         json.should == expected
       end
 
-      it "give a meaningful error if there is no front page" do
-        @wiki.unset_front_page!
+      it "should implicitly find the 'front-page' if no front page is set" do
+        @wiki.reload
+        @wiki.front_page_url = nil
+        @wiki.has_no_front_page = nil
+        @wiki.save!
+
+        json = api_call(:get, "/api/v1/courses/#{@course.id}/front_page",
+                        :controller=>"wiki_pages_api", :action=>"show", :format=>"json", :course_id=>"#{@course.id}")
+
+        expected = { "hide_from_students" => false,
+                     "editing_roles" => "teachers",
+                     "url" => @front_page.url,
+                     "html_url" => "http://www.example.com/courses/#{@course.id}/wiki/#{@front_page.url}",
+                     "created_at" => @front_page.created_at.as_json,
+                     "updated_at" => @front_page.updated_at.as_json,
+                     "title" => @front_page.title,
+                     "body" => @front_page.body,
+                     "published" => true,
+                     "front_page" => true,
+                     "locked_for_user" => false,
+        }
+        json.should == expected
+      end
+
+      it "should give a meaningful error if there is no front page" do
+        @front_page.workflow_state = 'deleted'
+        @front_page.save!
+        wiki = @front_page.wiki
+        wiki.unset_front_page!
 
         json = api_call(:get, "/api/v1/courses/#{@course.id}/front_page",
                         {:controller=>"wiki_pages_api", :action=>"show", :format=>"json", :course_id=>"#{@course.id}"},
-                      {}, {}, {:expected_status => 404})
+                        {}, {}, {:expected_status => 404})
 
         json['message'].should == "No front page has been set"
       end
@@ -549,6 +577,9 @@ describe "Pages API", :type => :integration do
 
       it "should un-set as front page" do
         wiki = @course.wiki
+        wiki.reload
+        wiki.has_front_page?.should be_true
+
         front_page = wiki.front_page
 
         json = api_call(:put, "/api/v1/courses/#{@course.id}/pages/#{front_page.url}",
@@ -561,7 +592,8 @@ describe "Pages API", :type => :integration do
         front_page.is_front_page?.should be_false
 
         wiki.reload
-        wiki.front_page.should be_nil
+        wiki.has_front_page?.should be_false
+        wiki.front_page.should be_new_record
 
         json['front_page'].should == false
       end

spec/models/wiki_spec.rb

@@ -34,18 +34,17 @@ describe Wiki do
     it "should unset front page" do
       @wiki.unset_front_page!
 
-      @wiki.front_page_url.should == nil
-      @wiki.front_page.should == nil
       @wiki.has_front_page?.should == false
+      @wiki.front_page_url.should == nil
     end
   end
 
   context "set_front_page_url!" do
     it "should set front_page_url" do
       @wiki.unset_front_page!
-
       new_url = "ponies4ever"
       @wiki.set_front_page_url!(new_url).should == true
+
       @wiki.has_front_page?.should == true
       @wiki.front_page_url.should == new_url
     end