my: groups: create: error if name already exists

- controller: error if name already exists (JSON)
- js model: handle ajax errors
- js controller: render ajax errors

app/assets/javascripts/controllers/groups_controller_create.coffee

@@ -20,14 +20,18 @@ class GroupsController.Create
     e.preventDefault()
     group = new App.Group
       name: @form.find("[name='name']").val()
-    if group.validate()
-      @el.remove()
-      group.create => document.location.reload true
-    else
-      App.DialogErrors.set @form, group.errors
 
+    unless group.validate()
+      return App.DialogErrors.set @form, group.errors
+
+    group.create (response)=>
+      if (err = response.error)?
+        App.DialogErrors.set(@form, [{text: err}])
+      else
+        do document.location.reload
+
   render: ->
     @el = App.render "groups/create"
-    
+
 window.App.GroupsController = {} unless window.App.GroupsController
 window.App.GroupsController.Create = GroupsController.Create

app/assets/javascripts/models/group.coffee

@@ -41,6 +41,9 @@ class Group
       success: (data)=>
         @refreshData data
         callback(data) if callback?
+      error: (xhr, status)=>
+        err = xhr?.responseJSON?.error || 'Error'
+        callback({error: err}) if callback?
 
   delete: (callback)->
     $.ajax

app/controllers/groups_controller.rb

@@ -36,9 +36,17 @@ def show
   end
 
   def create(name = params[:name] || raise("Name has to be present."))
-    group = current_user.groups.create(:name => name)
     respond_to do |format|
       format.json {
+
+        if Group.find_by(:name => name).present?
+          err = "Eine Gruppe mit diesem Namen existiert bereits!"
+          render(json: {:error => err}, :status => :bad_request) \
+            and return
+        end
+
+        group = current_user.groups.create!(:name => name)
+
         if group.persisted?
           render json: view_context.json_for(group)
         else

spec/features/workgroups_spec.rb

@@ -7,20 +7,26 @@
     @current_user = sign_in_as "normin"
   end
 
-  scenario "Create a new group", browser: :firefox do
-
-    visit my_groups_path
-
-    create_new_group_with_context_primary_action
-
-    name = Faker::Name.last_name
-    find("input[name='name']").set name
-
-    click_primary_action_of_modal
+  feature "Create a new group", browser: :firefox do
+    it "is OK with new name" do
+      name = Faker::Name.last_name
+      visit my_groups_path
+
+      create_group(name)
+
+      assert_modal_not_visible
+      expect(@current_user.groups.find_by_name(name)).to be
+    end
+    it "FAILS when name already exists" do
+      name = Faker::Name.last_name
+      visit my_groups_path
 
-    assert_modal_not_visible
-    expect(@current_user.groups.find_by_name(name)).to be
+      create_group(name)
+      assert_modal_not_visible
 
+      create_group(name)
+      assert_error_alert
+    end
   end
 
   scenario "Requiring name during group creation", browser: :firefox do
@@ -119,6 +125,12 @@ def create_new_group_with_context_primary_action
     assert_modal_visible
   end
 
+  def create_group(name)
+    create_new_group_with_context_primary_action
+    find("input[name='name']").set name
+    click_primary_action_of_modal
+  end
+
   def edit_one_group
     @group = @current_user.groups.first
     find(".ui-workgroups tr[data-id='#{@group.id}'] .button.edit-workgroup").click