Create a pending task when an issue is assigned to someone

app/services/base_service.rb

@@ -23,6 +23,10 @@ class BaseService
     EventCreateService.new
   end
 
+  def task_service
+    TaskService.new
+  end
+
   def log_info(message)
     Gitlab::AppLogger.info message
   end

app/services/issues/create_service.rb

@@ -9,6 +9,7 @@ module Issues
       if issue.save
         issue.update_attributes(label_ids: label_params)
         notification_service.new_issue(issue, current_user)
+        task_service.new_issue(issue, current_user)
         event_service.open_issue(issue, current_user)
         issue.create_cross_references!(current_user)
         execute_hooks(issue, 'open')

app/services/issues/update_service.rb

@@ -12,6 +12,7 @@ module Issues
       if issue.previous_changes.include?('assignee_id')
         create_assignee_note(issue)
         notification_service.reassigned_issue(issue, current_user)
+        task_service.reassigned_issue(issue, current_user)
       end
     end
 

app/services/task_service.rb

+# TaskService class
+#
+# Used for creating tasks on task queue after certain user action
+#
+# Ex.
+#   TaskService.new.new_issue(issue, current_user)
+#
+class TaskService
+  # When create an issue we should:
+  #
+  #  * creates a pending task for assignee if issue is assigned
+  #
+  def new_issue(issue, current_user)
+    if issue.is_assigned?
+      create_task(issue.project, issue, current_user, issue.assignee, Task::ASSIGNED)
+    end
+  end
+
+  # When we reassign an issue we should:
+  #
+  #  * creates a pending task for new assignee if issue is assigned
+  #
+  def reassigned_issue(issue, current_user)
+    if issue.is_assigned?
+      create_task(issue.project, issue, current_user, issue.assignee, Task::ASSIGNED)
+    end
+  end
+
+  private
+
+  def create_task(project, target, author, user, action)
+    attributes = {
+      project: project,
+      user_id: user.id,
+      author_id: author.id,
+      target_id: target.id,
+      target_type: target.class.name,
+      action: action
+    }
+
+    Task.create(attributes)
+  end
+end

spec/services/issues/create_service_spec.rb

@@ -3,14 +3,18 @@ require 'spec_helper'
 describe Issues::CreateService, services: true do
   let(:project) { create(:empty_project) }
   let(:user) { create(:user) }
+  let(:assignee) { create(:user) }
 
   describe :execute do
-    context "valid params" do
+    context 'valid params' do
       before do
         project.team << [user, :master]
+        project.team << [assignee, :master]
+
         opts = {
           title: 'Awesome issue',
-          description: 'please fix'
+          description: 'please fix',
+          assignee: assignee
         }
 
         @issue = Issues::CreateService.new(project, user, opts).execute
@@ -18,6 +22,20 @@ describe Issues::CreateService, services: true do
 
       it { expect(@issue).to be_valid }
       it { expect(@issue.title).to eq('Awesome issue') }
+      it { expect(@issue.assignee).to eq assignee }
+
+      it 'creates a pending task for new assignee' do
+        attributes = {
+          project: project,
+          author: user,
+          user: assignee,
+          target: @issue,
+          action: Task::ASSIGNED,
+          state: :pending
+        }
+
+        expect(Task.where(attributes).count).to eq 1
+      end
     end
   end
 end

spec/services/issues/update_service_spec.rb

@@ -78,6 +78,19 @@ describe Issues::UpdateService, services: true do
         expect(note).not_to be_nil
         expect(note.note).to eq 'Title changed from **Old title** to **New title**'
       end
+
+      it 'creates a pending task if being reassigned' do
+        attributes = {
+          project: project,
+          author: user,
+          user: user2,
+          target: issue,
+          action: Task::ASSIGNED,
+          state: :pending
+        }
+
+        expect(Task.where(attributes).count).to eq 1
+      end
     end
 
     context 'when Issue has tasks' do

spec/services/task_service_spec.rb

+require 'spec_helper'
+
+describe TaskService, services: true do
+  let(:service) { described_class.new }
+
+  describe 'Issues' do
+    let(:author) { create(:user) }
+    let(:john_doe) { create(:user) }
+    let(:project) { create(:empty_project, :public) }
+    let(:assigned_issue) { create(:issue, project: project, assignee: john_doe) }
+    let(:unassigned_issue) { create(:issue, project: project, assignee: nil) }
+
+    before do
+      project.team << [author, :developer]
+      project.team << [john_doe, :developer]
+    end
+
+    describe '#new_issue' do
+      it 'creates a pending task if assigned' do
+        service.new_issue(assigned_issue, author)
+
+        is_expected_to_create_pending_task(user: john_doe, target: assigned_issue, action: Task::ASSIGNED)
+      end
+
+      it 'does not create a task if unassigned' do
+        is_expected_to_not_create_task { service.new_issue(unassigned_issue, author) }
+      end
+    end
+
+    describe '#reassigned_issue' do
+      it 'creates a pending task for new assignee' do
+        unassigned_issue.update_attribute(:assignee, john_doe)
+        service.reassigned_issue(unassigned_issue, author)
+
+        is_expected_to_create_pending_task(user: john_doe, target: unassigned_issue, action: Task::ASSIGNED)
+      end
+
+      it 'does not create a task if unassigned' do
+        assigned_issue.update_attribute(:assignee, nil)
+
+        is_expected_to_not_create_task { service.reassigned_issue(assigned_issue, author) }
+      end
+    end
+  end
+
+  def is_expected_to_create_pending_task(attributes = {})
+    attributes.reverse_merge!(
+      project: project,
+      author: author,
+      state: :pending
+    )
+
+    expect(Task.where(attributes).count).to eq 1
+  end
+
+  def is_expected_to_not_create_task
+    expect { yield }.not_to change(Task, :count)
+  end
+end