Let members be invited from Add members pane.

app/assets/javascripts/users_select.js.coffee

@@ -8,6 +8,7 @@ class @UsersSelect
       @groupId = $(select).data('group-id')
       showNullUser = $(select).data('null-user')
       showAnyUser = $(select).data('any-user')
+      showEmailUser = $(select).data('email-user')
       firstUser = $(select).data('first-user')
       $(select).select2
@@ -19,20 +20,6 @@ class @UsersSelect
             data = { results: users }
             if query.term.length == 0
-              anyUser = {
-                name: 'Any',
-                avatar: null,
-                username: 'none',
-                id: null
-              }
-
-              nullUser = {
-                name: 'Unassigned',
-                avatar: null,
-                username: 'none',
-                id: 0
-              }
-
               if firstUser
                 # Move current user to the front of the list
                 for obj, index in data.results
@@ -40,11 +27,34 @@ class @UsersSelect
                     data.results.splice(index, 1)
                     data.results.unshift(obj)
                     break
+
               if showNullUser
+                nullUser = {
+                  name: 'Unassigned',
+                  avatar: null,
+                  username: 'none',
+                  id: 0
+                }
                 data.results.unshift(nullUser)
+
               if showAnyUser
+                anyUser = {
+                  name: 'Any',
+                  avatar: null,
+                  username: 'none',
+                  id: null
+                }
                 data.results.unshift(anyUser)
+            if showEmailUser && data.results.length == 0 && query.term.match(/^[^@]+@[^@]+$/)
+              emailUser = {
+                name: "Invite \"#{query.term}\"",
+                avatar: null,
+                username: query.term,
+                id: query.term
+              }
+              data.results.unshift(emailUser)
+
             query.callback(data)
         initSelection: (element, callback) =>

app/controllers/projects/project_members_controller.rb

@@ -36,8 +36,7 @@ class Projects::ProjectMembersController < Projects::ApplicationController
   end
   def create
-    users = User.where(id: params[:user_ids].split(','))
-    @project.team << [users, params[:access_level]]
+    @project.team.add_users(params[:user_ids].split(','), params[:access_level], current_user)
     redirect_to namespace_project_project_members_path(@project.namespace, @project)
   end

app/helpers/selects_helper.rb

@@ -8,6 +8,7 @@ module SelectsHelper
     null_user = opts[:null_user] || false
     any_user = opts[:any_user] || false
+    email_user = opts[:email_user] || false
     first_user = opts[:first_user] && current_user ? current_user.username : false
     html = {
@@ -15,6 +16,7 @@ module SelectsHelper
       'data-placeholder' => placeholder,
       'data-null-user' => null_user,
       'data-any-user' => any_user,
+      'data-email-user' => email_user,
       'data-first-user' => first_user
     }

app/models/group.rb

@@ -47,10 +47,24 @@ class Group < Namespace
   end
   def add_users(user_ids, access_level, current_user = nil)
-    user_ids.compact.each do |user_id|
-      member = self.group_members.find_or_initialize_by(user_id: user_id)
-      member.access_level = access_level
+    users = user_ids.map do |user_id|
+      (user_id if user_id.is_a?(User)) ||
+        User.find_by(id: user_id) || 
+        User.find_by(email: user_id) || 
+        user_id
+    end
+
+    users.compact.each do |user|
+      if user.is_a?(User)
+        member = self.group_members.find_or_initialize_by(user_id: user.id)
+      else
+        member = self.group_members.build
+        member.invite_email = user
+      end
+
       member.created_by ||= current_user
+      member.access_level = access_level
+
       member.save
     end
   end

app/models/members/project_member.rb

@@ -60,12 +60,28 @@ class ProjectMember < Member
                        raise "Non valid access"
                      end
+      users = user_ids.map do |user_id|
+        (user_id if user_id.is_a?(User)) ||
+          User.find_by(id: user_id) || 
+          User.find_by(email: user_id) || 
+          user_id
+      end
+
       ProjectMember.transaction do
         project_ids.each do |project_id|
-          user_ids.each do |user_id|
-            member = ProjectMember.new(access_level: access_level, user_id: user_id)
-            member.source_id = project_id
+          project = Project.find(project_id)
+
+          users.each do |user|
+            if user.is_a?(User)
+              member = project.project_members.find_or_initialize_by(user_id: user.id)
+            else
+              member = project.project_members.build
+              member.invite_email = user
+            end
+
             member.created_by ||= current_user
+            member.access_level = access_level
+
             member.save
           end
         end

app/views/admin/groups/show.html.haml

@@ -60,7 +60,7 @@
         = form_tag members_update_admin_group_path(@group), id: "new_project_member", class: "bulk_import", method: :put  do
           %div
-            = users_select_tag(:user_ids, multiple: true)
+            = users_select_tag(:user_ids, multiple: true, email_user: true)
           %div.prepend-top-10
             = select_tag :access_level, options_for_select(GroupMember.access_level_roles), class: "project-access-select select2"
           %hr

app/views/groups/group_members/_new_group_member.html.haml

 = form_for @group_member, url: group_group_members_path(@group), html: { class: 'form-horizontal users-group-form' } do |f|
   .form-group
     = f.label :user_ids, "People", class: 'control-label'
-    .col-sm-10= users_select_tag(:user_ids, multiple: true, class: 'input-large', scope: :all)
+    .col-sm-10
+      = users_select_tag(:user_ids, multiple: true, class: 'input-large', scope: :all, email_user: true)
+      .help-block
+        Search for existing users or invite new ones using their email address.
   .form-group
     = f.label :access_level, "Group Access", class: 'control-label'

app/views/projects/project_members/_new_project_member.html.haml

 = form_for @project_member, as: :project_member, url: namespace_project_project_members_path(@project.namespace, @project), html: { class: 'form-horizontal users-project-form' } do |f|
   .form-group
     = f.label :user_ids, "People", class: 'control-label'
-    .col-sm-10= users_select_tag(:user_ids, multiple: true, class: 'input-large', scope: :all)
+    .col-sm-10
+      = users_select_tag(:user_ids, multiple: true, class: 'input-large', scope: :all, email_user: true)
+      .help-block
+        Search for existing users or invite new ones using their email address.
   .form-group
     = f.label :access_level, "Project Access", class: 'control-label'