added project mailer

app/interactors/projects/destroy.rb

@@ -2,8 +2,10 @@ module Projects
   class Destroy
     include Interactor
 
-    delegate :project, to: :context
-
+    delegate :project, :user, to: :context
+    before do
+      ProjectMailer.project_deleted(project).deliver_later
+    end
     def call
       project.destroy
     end

app/interactors/projects/update.rb

@@ -2,8 +2,10 @@ module Projects
   class Update
     include Interactor
 
-    delegate :project, :project_params, to: :context
-
+    delegate :project, :project_params, :user, to: :context
+    before do
+      ProjectMailer.project_updated(project).deliver_later
+    end
     def call
       context.fail!(error: "Invalid data") unless project.update(project_params)
     end

app/mailers/project_mailer.rb

@@ -4,4 +4,16 @@ def project_created(project, user)
 
     mail(to: user.email)
   end
+
+  def project_updated(project)
+    @project = project
+
+    mail(to: project.users.pluck(:email))
+  end
+
+  def project_deleted(project)
+    @project = project
+
+    mail(to: project.users.pluck(:email))
+  end
 end

app/views/project_mailer/project_deleted.html.erb

@@ -0,0 +1 @@
+<h1>Congratulations! You project was deleted -- "<%= @project.name %>"!</h1>

app/views/project_mailer/project_deleted.txt.erb

@@ -0,0 +1 @@
+Congratulations! You project was deleted -- "<%= @project.name %>"!

app/views/project_mailer/project_updated.html.erb

@@ -0,0 +1,2 @@
+<h1>Project updated.</h1>
+<p>Congratulations! Project was updated -- "<%= @project.name %>"!</p>

app/views/project_mailer/project_updated.txt.erb

@@ -0,0 +1 @@
+Congratulations! Project was updated -- "<%= @project.name %>"!