Merge branch '18755-fix-destroy-project-causes-post_decline_request-to-be-executed' into 'master'

Resolve "Destroying a project causes post_decline_request to be executed"

## What does this MR do?

Ensure we don't send "access request declined" to access requesters when a project is deleted.

## Are there points in the code the reviewer needs to double check?

I've created a service to decouple the notification sending from the AR model.

## Why was this MR needed?

Because there was an issue.

## What are the relevant issue numbers?

Fixes #18755, #18750.

## Does this MR meet the acceptance criteria?

- [x] No CHANGELOG needed.
- [x] Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4744

3 files changed, 1 insertions, 30 deletions

diff --git a/app/models/member.rb b/app/models/member.rb
index 4ee3f1bb5c2..c74a16367db 100644
--- a/app/models/member.rb
+++ b/app/models/member.rb
@@ -48,7 +48,6 @@ class Member < ActiveRecord::Base
   after_create :post_create_hook, unless: [:pending?, :importing?]
   after_update :post_update_hook, unless: [:pending?, :importing?]
   after_destroy :post_destroy_hook, unless: :pending?
-  after_destroy :post_decline_request, if: :request?
 
   delegate :name, :username, :email, to: :user, prefix: true
 
@@ -188,7 +187,7 @@ class Member < ActiveRecord::Base
   end
 
   def send_request
-    # override in subclass
+    notification_service.new_access_request(self)
   end
 
   def post_create_hook
@@ -215,10 +214,6 @@ class Member < ActiveRecord::Base
     post_create_hook
   end
 
-  def post_decline_request
-    # override in subclass
-  end
-
   def system_hook_service
     SystemHooksService.new
   end
diff --git a/app/models/members/group_member.rb b/app/models/members/group_member.rb
index 363db877968..2f13d339c89 100644
--- a/app/models/members/group_member.rb
+++ b/app/models/members/group_member.rb
@@ -33,12 +33,6 @@ class GroupMember < Member
     super
   end
 
-  def send_request
-    notification_service.new_group_access_request(self)
-
-    super
-  end
-
   def post_create_hook
     notification_service.new_group_member(self)
 
@@ -64,10 +58,4 @@ class GroupMember < Member
 
     super
   end
-
-  def post_decline_request
-    notification_service.decline_group_access_request(self)
-
-    super
-  end
 end
diff --git a/app/models/members/project_member.rb b/app/models/members/project_member.rb
index 250ee04fd1d..e9d3a82ba15 100644
--- a/app/models/members/project_member.rb
+++ b/app/models/members/project_member.rb
@@ -111,12 +111,6 @@ class ProjectMember < Member
     super
   end
 
-  def send_request
-    notification_service.new_project_access_request(self)
-
-    super
-  end
-
   def post_create_hook
     unless owner?
       event_service.join_project(self.project, self.user)
@@ -152,12 +146,6 @@ class ProjectMember < Member
     super
   end
 
-  def post_decline_request
-    notification_service.decline_project_access_request(self)
-
-    super
-  end
-
   def event_service
     EventCreateService.new
   end