Include user_username in user_(add_to/remove_from)_(project/group) system hooks.

app/services/system_hooks_service.rb

@@ -100,6 +100,7 @@ class SystemHooksService
       project_path: model.project.path,
       project_path_with_namespace: model.project.path_with_namespace,
       project_id: model.project.id,
+      user_username: model.user.username,
       user_name: model.user.name,
       user_email: model.user.email,
       access_level: model.human_access,
@@ -112,6 +113,7 @@ class SystemHooksService
       group_name: model.group.name,
       group_path: model.group.path,
       group_id: model.group.id,
+      user_username: model.user.username,
       user_name: model.user.name,
       user_email: model.user.email,
       user_id: model.user.id,

doc/system_hooks/system_hooks.md

@@ -96,6 +96,7 @@ X-Gitlab-Event: System Hook
  "project_path_with_namespace": "jsmith/storecloud",
                   "user_email": "johnsmith@gmail.com",
                    "user_name": "John Smith",
+               "user_username": "johnsmith",
                      "user_id": 41,
           "project_visibility": "private",
 }
@@ -115,6 +116,7 @@ X-Gitlab-Event: System Hook
  "project_path_with_namespace": "jsmith/storecloud",
                   "user_email": "johnsmith@gmail.com",
                    "user_name": "John Smith",
+               "user_username": "johnsmith",
                      "user_id": 41,
           "project_visibility": "private",
 }
@@ -217,6 +219,7 @@ X-Gitlab-Event: System Hook
     "group_path": "storecloud",
     "user_email": "johnsmith@gmail.com",
      "user_name": "John Smith",
+ "user_username": "johnsmith",
        "user_id": 41
 }
 ```
@@ -233,6 +236,7 @@ X-Gitlab-Event: System Hook
     "group_path": "storecloud",
     "user_email": "johnsmith@gmail.com",
      "user_name": "John Smith",
+ "user_username": "johnsmith",
        "user_id": 41
 }
 ```

spec/services/system_hooks_service_spec.rb

@@ -13,8 +13,8 @@ describe SystemHooksService, services: true do
     it { expect(event_data(user, :destroy)).to include(:event_name, :name, :created_at, :updated_at, :email, :user_id, :username) }
     it { expect(event_data(project, :create)).to include(:event_name, :name, :created_at, :updated_at, :path, :project_id, :owner_name, :owner_email, :project_visibility) }
     it { expect(event_data(project, :destroy)).to include(:event_name, :name, :created_at, :updated_at, :path, :project_id, :owner_name, :owner_email, :project_visibility) }
-    it { expect(event_data(project_member, :create)).to include(:event_name, :created_at, :updated_at, :project_name, :project_path, :project_path_with_namespace, :project_id, :user_name, :user_email, :access_level, :project_visibility) }
-    it { expect(event_data(project_member, :destroy)).to include(:event_name, :created_at, :updated_at, :project_name, :project_path, :project_path_with_namespace, :project_id, :user_name, :user_email, :access_level, :project_visibility) }
+    it { expect(event_data(project_member, :create)).to include(:event_name, :created_at, :updated_at, :project_name, :project_path, :project_path_with_namespace, :project_id, :user_name, :user_username, :user_email, :access_level, :project_visibility) }
+    it { expect(event_data(project_member, :destroy)).to include(:event_name, :created_at, :updated_at, :project_name, :project_path, :project_path_with_namespace, :project_id, :user_name, :user_username, :user_email, :access_level, :project_visibility) }
     it { expect(event_data(key, :create)).to include(:username, :key, :id) }
     it { expect(event_data(key, :destroy)).to include(:username, :key, :id) }
 
@@ -50,13 +50,13 @@ describe SystemHooksService, services: true do
     it do
       expect(event_data(group_member, :create)).to include(
         :event_name, :created_at, :updated_at, :group_name, :group_path, 
-        :group_id, :user_id, :user_name, :user_email, :group_access
+        :group_id, :user_id, :user_username, :user_name, :user_email, :group_access
       )
     end
     it do
       expect(event_data(group_member, :destroy)).to include(
         :event_name, :created_at, :updated_at, :group_name, :group_path, 
-        :group_id, :user_id, :user_name, :user_email, :group_access
+        :group_id, :user_id, :user_username, :user_name, :user_email, :group_access
       )
     end
   end