Redirects with custom flash messages

app/controllers/devise/masquerades_controller.rb

@@ -15,7 +15,7 @@ def show
     if send("#{masqueraded_resource_name}_masquerade?")
       resource = masquerading_current_user
 
-      go_back(resource, path: after_masquerade_full_path_for(resource))
+      go_back(resource, path: after_masquerade_full_path_for(resource), message: "")
     else
       masqueradable_resource = find_masqueradable_resource
 
@@ -33,14 +33,14 @@ def show
 
       masquerade_sign_in(resource)
 
-      go_back(resource, path: after_masquerade_full_path_for(resource))
+      go_back(resource, path: after_masquerade_full_path_for(resource), message: after_masquerade_flash_message(resource))
     end
   end
 
   def back
     unless send("#{masqueraded_resource_name}_masquerade?")
       resource = send("current_#{masqueraded_resource_name}")
-      go_back(resource, path: after_back_masquerade_path_for(resource))
+      go_back(resource, path: after_back_masquerade_path_for(resource), message: "")
     else
       masqueradable_resource = send("current_#{masqueraded_resource_name}")
 
@@ -54,7 +54,7 @@ def back
       sign_in(resource)
       request.env['devise.skip_trackable'] = nil
 
-      go_back(resource, path: after_back_masquerade_path_for(resource))
+      go_back(resource, path: after_back_masquerade_path_for(resource), message: after_back_masquerade_flash_message(masqueradable_resource))
 
       cleanup_masquerade_owner_session(masqueradable_resource)
     end
@@ -88,10 +88,12 @@ def find_owner_resource(masqueradable_resource)
     end
   end
 
-  def go_back(user, path:)
+  def go_back(user, path:, message:)
     if Devise.masquerade_routes_back
+      flash[:notice] = message
       redirect_back(fallback_location: path)
     else
+      flash[:notice] = message
       redirect_to path
     end
   end
@@ -132,6 +134,10 @@ def after_masquerade_path_for(resource)
     '/'
   end
 
+  def after_masquerade_flash_message(resource)
+    ""
+  end
+
   def after_masquerade_full_path_for(resource)
     after_masquerade_path_for(resource)
   end
@@ -140,6 +146,10 @@ def after_back_masquerade_path_for(resource)
     '/'
   end
 
+  def after_back_masquerade_flash_message(resource)
+    ""
+  end
+
   def save_masquerade_owner_session(masqueradable_resource)
     guid = SecureRandom.uuid
 

spec/controllers/devise/masquerades_controller_spec.rb

@@ -33,12 +33,16 @@
         let(:mask) { create(:user) }
 
         before do
+          allow_any_instance_of(described_class).to(
+            receive(:after_masquerade_flash_message).with(mask).and_return("You are logged as an user"))
+
           get :show, params: { id: mask.id, masquerade: mask.masquerade_key }
         end
 
         it { expect(cache_read(mask)).to be }
         it { expect(session["warden.user.user.key"].first.first).to eq(mask.id) }
         it { should redirect_to('/') }
+        it { expect(flash[:notice]).to match("You are logged as an user") }
 
         context 'and back' do
           before { get :back }
@@ -81,12 +85,17 @@
 
         context 'and back' do
           before do
+            allow_any_instance_of(described_class).to(
+              receive(:after_back_masquerade_flash_message).with(mask).and_return("You logged out from user's session")
+            )
+
             get :show, params: { id: mask.id, masquerade: mask.masquerade_key }
 
             get :back
           end
 
           it { should redirect_to(masquerade_page) }
+          it { expect(flash[:notice]).to match("You logged out from user's session") }
         end # context
 
         context 'and back fallback if http_referer not present' do