Notify moderators when someone is automatically blocked because of spam flags

app/services/spam_rules_enforcer.rb

@@ -2,6 +2,8 @@
 # receive, their trust level, etc.
 class SpamRulesEnforcer
 
+  include Rails.application.routes.url_helpers
+
   # The exclamation point means that this method may make big changes to posts and the user.
   def self.enforce!(user)
     SpamRulesEnforcer.new(user).enforce!
@@ -51,6 +53,7 @@ class SpamRulesEnforcer
   def punish_user
     Post.update_all(["hidden = true, hidden_reason_id = COALESCE(hidden_reason_id, ?)", Post.hidden_reasons[:new_user_spam_threshold_reached]], user_id: @user.id)
     SystemMessage.create(@user, :too_many_spam_flags)
+    notify_moderators
     @user.blocked = true
     @user.save
   end
@@ -61,4 +64,18 @@ class SpamRulesEnforcer
     @user.save
   end
 
+
+  private
+
+    def notify_moderators
+      title = I18n.t("system_messages.user_automatically_blocked.subject_template", {username: @user.username})
+      raw_body = I18n.t("system_messages.user_automatically_blocked.text_body_template", {username: @user.username, blocked_user_url: admin_user_path(@user.username)})
+      PostCreator.create( Discourse.system_user,
+                          target_group_names: [Group[:moderators].name],
+                          archetype: Archetype.private_message,
+                          subtype: TopicSubtype.system_message,
+                          title: title,
+                          raw: raw_body )
+    end
+
 end

config/locales/server.en.yml

@@ -861,6 +861,13 @@ en:
 
         For additional guidance, please refer to our [FAQ](%{base_url}/faq).
 
+    user_automatically_blocked:
+      subject_template: "User %{username} was automatically blocked"
+      text_body_template: |
+        This is an automated message to inform you that [%{username}](%{blocked_user_url}) has been automatically blocked because too many people submitted flags against %{username}'s post(s).
+
+        Please [review the flags](/admin/flags). If %{username} should not be blocked from posting, click the unblock button on [the admin user page](%{blocked_user_url}).
+
     unblocked:
       subject_template: "Account unblocked"
       text_body_template: |

spec/integration/spam_rules_spec.rb

@@ -11,6 +11,7 @@ describe PostAction do
   end
 
   Given!(:admin)     { Fabricate(:admin) } # needed to send a system message
+  Given!(:moderator) { Fabricate(:moderator) }
   Given(:user1)      { Fabricate(:user) }
   Given(:user2)      { Fabricate(:user) }
 
@@ -33,6 +34,7 @@ describe PostAction do
       context 'one spam post is flagged enough times by enough users' do
         Given!(:another_topic)          { Fabricate(:topic) }
         Given!(:private_messages_count) { spammer.private_topics_count }
+        Given!(:mod_pm_count)           { moderator.private_topics_count }
 
         When { PostAction.act(user2, spam_post, PostActionType.types[:spam]) }
 
@@ -48,7 +50,7 @@ describe PostAction do
 
         # The following cases describe when a staff user takes some action, but the user
         # still won't be able to make posts.
-        # A staff user needs to clear the spam flag from the user record.
+        # A staff user needs to clear the blocked flag from the user record.
 
         context "a post's flags are cleared" do
           When { PostAction.clear_flags!(spam_post, admin); spammer.reload }

spec/services/spam_rules_enforcer_spec.rb

@@ -117,8 +117,14 @@ describe SpamRulesEnforcer do
       expect(Guardian.new(user).can_create_post?(nil)).to be_false
     end
 
-    it 'sends a system message to the user' do
+    it 'sends private messages to the user and to moderators' do
       SystemMessage.expects(:create).with(user, anything, anything)
+      moderator = Fabricate(:moderator)
+      PostCreator.expects(:create).with do |from_user, opts|
+        from_user.id == admin.id &&
+          opts[:target_group_names] && opts[:target_group_names].include?(Group[:moderators].name) &&
+          opts[:archetype] == Archetype.private_message
+      end.returns(stub_everything)
       subject.punish_user
     end