Server side code for Watching First Post Only

app/models/category.rb

@@ -17,6 +17,7 @@ class Category < ActiveRecord::Base
   belongs_to :latest_post, class_name: "Post"
 
   has_many :topics
+  has_many :category_users
   has_many :category_featured_topics
   has_many :featured_topics, through: :category_featured_topics, source: :topic
 

app/models/category_user.rb

@@ -1,3 +1,5 @@
+require_dependency 'notification_levels'
+
 class CategoryUser < ActiveRecord::Base
   belongs_to :category
   belongs_to :user
@@ -11,11 +13,7 @@ class CategoryUser < ActiveRecord::Base
   end
 
   def self.notification_levels
-    @notification_levels ||= Enum.new(muted: 0,
+    NotificationLevels.all
-                                      regular: 1,
-                                      tracking: 2,
-                                      watching: 3,
-                                      watching_first_post: 4)
   end
 
   def self.watching_levels

app/models/group_user.rb

@@ -1,3 +1,5 @@
+require_dependency 'notification_levels'
+
 class GroupUser < ActiveRecord::Base
   belongs_to :group, counter_cache: "user_count"
   belongs_to :user
@@ -10,6 +12,10 @@ class GroupUser < ActiveRecord::Base
 
   after_save :grant_trust_level
 
+  def self.notification_levels
+    NotificationLevels.all
+  end
+
   protected
 
   def set_primary_group

app/models/notification.rb

@@ -42,7 +42,8 @@ class Notification < ActiveRecord::Base
                         invited_to_topic: 13,
                         custom: 14,
                         group_mentioned: 15,
-                        group_message_summary: 16
+                        group_message_summary: 16,
+                        watching_first_post: 17
                        )
   end
 
@@ -107,11 +108,6 @@ class Notification < ActiveRecord::Base
     end
   end
 
-  def text_description
-    link = block_given? ? yield : ""
-    I18n.t("notification_types.#{Notification.types[notification_type]}", data_hash.merge(link: link))
-  end
-
   def url
     topic.relative_url(post_number) if topic.present?
   end

app/models/tag_user.rb

@@ -1,9 +1,11 @@
+require_dependency 'notification_levels'
+
 class TagUser < ActiveRecord::Base
   belongs_to :tag
   belongs_to :user
 
   def self.notification_levels
-    TopicUser.notification_levels
+    NotificationLevels.all
   end
 
   def self.change(user_id, tag_id, level)

app/models/topic.rb

@@ -79,6 +79,7 @@ class Topic < ActiveRecord::Base
   end
 
   belongs_to :category
+  has_many :category_users, through: :category
   has_many :posts
   has_many :ordered_posts, -> { order(post_number: :asc) }, class_name: "Post"
   has_many :topic_allowed_users
@@ -94,6 +95,7 @@ class Topic < ActiveRecord::Base
 
   has_many :topic_tags, dependent: :destroy
   has_many :tags, through: :topic_tags
+  has_many :tag_users, through: :tags
 
   has_one :top_topic
   belongs_to :user

app/models/topic_user.rb

@@ -1,3 +1,5 @@
+require_dependency 'notification_levels'
+
 class TopicUser < ActiveRecord::Base
   belongs_to :user
   belongs_to :topic
@@ -17,10 +19,7 @@ class TopicUser < ActiveRecord::Base
 
     # Enums
     def notification_levels
-      @notification_levels ||= Enum.new(muted: 0,
+      NotificationLevels.topic_levels
-                                        regular: 1,
-                                        tracking: 2,
-                                        watching: 3)
     end
 
     def notification_reasons

app/services/post_alerter.rb

@@ -107,6 +107,42 @@ class PostAlerter
     end
 
     sync_group_mentions(post, mentioned_groups)
+
+    if post.post_number == 1
+      topic = post.topic
+
+      if topic.present?
+        cat_watchers = topic.category_users
+                            .where(notification_level: CategoryUser.notification_levels[:watching_first_post])
+                            .pluck(:user_id)
+
+        tag_watchers = topic.tag_users
+                            .where(notification_level: TagUser.notification_levels[:watching_first_post])
+                            .pluck(:user_id)
+
+        group_ids = post.user.groups.pluck(:id)
+        group_watchers = GroupUser.where(group_id: group_ids,
+                                         notification_level: GroupUser.notification_levels[:watching_first_post])
+                                  .pluck(:user_id)
+
+        watchers = [cat_watchers, tag_watchers, group_watchers].flatten
+
+        notify_first_post_watchers(post, watchers)
+      end
+    end
+  end
+
+  def notify_first_post_watchers(post, user_ids)
+    return if user_ids.blank?
+
+    user_ids.uniq!
+
+    # Don't notify the OP
+    user_ids -= [post.user_id]
+
+    User.where(id: user_ids).each do |u|
+      create_notification(u, Notification.types[:watching_first_post], post)
+    end
   end
 
   def sync_group_mentions(post, mentioned_groups)

config/locales/client.en.yml

@@ -1117,6 +1117,8 @@ en:
       linked: "<i title='linked post' class='fa fa-link'></i><p><span>{{username}}</span> {{description}}</p>"
       granted_badge: "<i title='badge granted' class='fa fa-certificate'></i><p>Earned '{{description}}'</p>"
 
+      watching_first_post: "<i title='new topic' class='fa fa-dot-circle-o'></i><p><span>New Topic</span> {{description}}</p>"
+
       group_message_summary:
           one: "<i title='messages in group inbox' class='fa fa-group'></i><p> {{count}} message in your {{group_name}} inbox</p>"
           other: "<i title='messages in group inbox' class='fa fa-group'></i><p> {{count}} messages in your {{group_name}} inbox</p>"

config/locales/server.en.yml

@@ -1383,22 +1383,6 @@ en:
       email_polling_disabled: "You must enable either manual or POP3 polling before enabling reply by email."
       user_locale_not_enabled: "You must first enable 'allow user locale' before enabling this setting."
 
-  notification_types:
-    group_mentioned: "%{group_name} was mentioned in %{link}"
-    mentioned: "%{display_username} mentioned you in %{link}"
-    liked: "%{display_username} liked your post in %{link}"
-    replied: "%{display_username} replied to your post in %{link}"
-    quoted: "%{display_username} quoted your post in %{link}"
-    edited: "%{display_username} edited your post in %{link}"
-    posted: "%{display_username} posted in %{link}"
-    moved_post: "%{display_username} moved your post to %{link}"
-    private_message: "%{display_username} sent you a message: %{link}"
-    invited_to_private_message: "%{display_username} invited you to a message: %{link}"
-    invited_to_topic: "%{display_username} invited you to %{link}"
-    invitee_accepted: "%{display_username} accepted your invitation"
-    linked: "%{display_username} linked you in %{link}"
-    granted_badge: "You earned %{link}"
-
   search:
     within_post: "#%{post_number} by %{username}"
     types:

lib/notification_levels.rb

@@ -0,0 +1,16 @@
+module NotificationLevels
+  def self.all
+    @all_levels ||= Enum.new(muted: 0,
+                             regular: 1,
+                             tracking: 2,
+                             watching: 3,
+                             watching_first_post: 4)
+  end
+
+  def self.topic_levels
+    @topic_levels ||= Enum.new(muted: 0,
+                               regular: 1,
+                               tracking: 2,
+                               watching: 3)
+  end
+end

spec/integrity/i18n_spec.rb

@@ -23,13 +23,6 @@ describe "i18n integrity checks" do
     end
   end
 
-  it "needs an i18n key (notification_types) for each Notification type" do
-    Notification.types.each_key do |type|
-      next if type == :custom || type == :group_message_summary
-      expect(I18n.t("notification_types.#{type}")).not_to match(/translation missing/)
-    end
-  end
-
   it "has valid YAML for client" do
     Dir["#{Rails.root}/config/locales/client.*.yml"].each do |f|
       locale = /.*\.([^.]{2,})\.yml$/.match(f)[1]

spec/services/post_alerter_spec.rb

@@ -326,4 +326,42 @@ describe PostAlerter do
     end
   end
 
+  describe "watching_first_post" do
+    let(:group) { Fabricate(:group) }
+    let(:user) { Fabricate(:user) }
+    let(:category) { Fabricate(:category) }
+    let(:tag)  { Fabricate(:tag) }
+    let(:topic) { Fabricate(:topic, category: category, tags: [tag]) }
+    let(:post) { Fabricate(:post, topic: topic) }
+
+    it "doesn't notify people who aren't watching" do
+      PostAlerter.post_created(post)
+      expect(user.notifications.where(notification_type: Notification.types[:watching_first_post]).count).to eq(0)
+    end
+
+    it "notifies the user who is following the first post category" do
+      level = CategoryUser.notification_levels[:watching_first_post]
+      CategoryUser.set_notification_level_for_category(user, level, category.id)
+      PostAlerter.post_created(post)
+      expect(user.notifications.where(notification_type: Notification.types[:watching_first_post]).count).to eq(1)
+    end
+
+    it "notifies the user who is following the first post tag" do
+      level = TagUser.notification_levels[:watching_first_post]
+      TagUser.change(user.id, tag.id, level)
+      PostAlerter.post_created(post)
+      expect(user.notifications.where(notification_type: Notification.types[:watching_first_post]).count).to eq(1)
+    end
+
+    it "notifies the user who is following the first post group" do
+      GroupUser.create(group_id: group.id, user_id: user.id)
+      GroupUser.create(group_id: group.id, user_id: post.user.id)
+
+      level = GroupUser.notification_levels[:watching_first_post]
+      GroupUser.where(user_id: user.id, group_id: group.id).update_all(notification_level: level)
+
+      PostAlerter.post_created(post)
+      expect(user.notifications.where(notification_type: Notification.types[:watching_first_post]).count).to eq(1)
+    end
+  end
 end