Merge branch 'share-project-ce' into 'master'

Bring from EE: Share Project with Group

- [x] Models and migrations
- [x] Logic, UI
- [x] Tests
- [x] Documentation
- [x] Share with group lock
- [x] Api feature
- [x] Api docs
- [x] Api tests
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

For #12831 

cc @DouweM @rspeicher @vsizov

See merge request !3186

app/assets/javascripts/dispatcher.js.coffee

@@ -104,6 +104,8 @@ class Dispatcher
         new ProjectFork()
       when 'projects:artifacts:browse'
         new BuildArtifacts()
+      when 'projects:group_links:index'
+        new GroupsSelect()
 
     switch path.first()
       when 'admin'

app/controllers/groups_controller.rb

@@ -46,6 +46,8 @@ class GroupsController < Groups::ApplicationController
     @projects = @projects.sort(@sort = params[:sort])
     @projects = @projects.page(params[:page]).per(PER_PAGE) if params[:filter_projects].blank?
 
+    @shared_projects = @group.shared_projects
+
     respond_to do |format|
       format.html
 
@@ -133,7 +135,7 @@ class GroupsController < Groups::ApplicationController
   end
 
   def group_params
-    params.require(:group).permit(:name, :description, :path, :avatar, :public)
+    params.require(:group).permit(:name, :description, :path, :avatar, :public, :share_with_group_lock)
   end
 
   def load_events

app/controllers/projects/group_links_controller.rb

+class Projects::GroupLinksController < Projects::ApplicationController
+  layout 'project_settings'
+  before_action :authorize_admin_project!
+
+  def index
+    @group_links = project.project_group_links.all
+  end
+
+  def create
+    link = project.project_group_links.new
+    link.group_id = params[:link_group_id]
+    link.group_access = params[:link_group_access]
+    link.save
+
+    redirect_to namespace_project_group_links_path(project.namespace, project)
+  end
+
+  def destroy
+    project.project_group_links.find(params[:id]).destroy
+
+    redirect_to namespace_project_group_links_path(project.namespace, project)
+  end
+end

app/controllers/projects/project_members_controller.rb

@@ -27,6 +27,7 @@ class Projects::ProjectMembersController < Projects::ApplicationController
     end
 
     @project_member = @project.project_members.new
+    @project_group_links = @project.project_group_links
   end
 
   def create

app/finders/projects_finder.rb

@@ -43,7 +43,8 @@ class ProjectsFinder
     if current_user
       [
         group_projects_for_user(current_user, group),
-        group.projects.public_and_internal_only
+        group.projects.public_and_internal_only,
+        group.shared_projects.visible_to_user(current_user)
       ]
     else
       [group.projects.public_only]

app/models/group.rb

@@ -23,6 +23,8 @@ class Group < Namespace
   has_many :group_members, dependent: :destroy, as: :source, class_name: 'GroupMember'
   alias_method :members, :group_members
   has_many :users, through: :group_members
+  has_many :project_group_links, dependent: :destroy
+  has_many :shared_projects, through: :project_group_links, source: :project
 
   validate :avatar_type, if: ->(user) { user.avatar.present? && user.avatar_changed? }
   validates :avatar, file_size: { maximum: 200.kilobytes.to_i }

app/models/project.rb

@@ -151,6 +151,8 @@ class Project < ActiveRecord::Base
   has_many :releases, dependent: :destroy
   has_many :lfs_objects_projects, dependent: :destroy
   has_many :lfs_objects, through: :lfs_objects_projects
+  has_many :project_group_links, dependent: :destroy
+  has_many :invited_groups, through: :project_group_links, source: :group
   has_many :todos, dependent: :destroy
 
   has_one :import_data, dependent: :destroy, class_name: "ProjectImportData"
@@ -899,6 +901,10 @@ class Project < ActiveRecord::Base
     jira_tracker? && jira_service.active
   end
 
+  def allowed_to_share_with_group?
+    !namespace.share_with_group_lock
+  end
+
   def ci_commit(sha)
     ci_commits.find_by(sha: sha)
   end

app/models/project_group_link.rb

+class ProjectGroupLink < ActiveRecord::Base
+  GUEST     = 10
+  REPORTER  = 20
+  DEVELOPER = 30
+  MASTER    = 40
+
+  belongs_to :project
+  belongs_to :group
+
+  validates :project_id, presence: true
+  validates :group_id, presence: true
+  validates :group_id, uniqueness: { scope: [:project_id], message: "already shared with this group" }
+  validates :group_access, presence: true
+  validates :group_access, inclusion: { in: Gitlab::Access.values }, presence: true
+  validate :different_group
+
+  def self.access_options
+    Gitlab::Access.options
+  end
+
+  def self.default_access
+    DEVELOPER
+  end
+
+  def human_access
+    self.class.access_options.key(self.group_access)
+  end
+
+  private 
+
+  def different_group
+    if self.group && self.project && self.project.group == self.group
+      errors.add(:base, "Project cannot be shared with the project it is in.")
+    end
+  end
+end

app/models/project_team.rb

@@ -160,7 +160,27 @@ class ProjectTeam
       end
     end
 
-    access.max
+    if project.invited_groups.any? && project.allowed_to_share_with_group?
+      access << max_invited_level(user_id)
+    end
+
+    access.compact.max
+  end
+
+
+  def max_invited_level(user_id)
+    project.project_group_links.map do |group_link|
+      invited_group = group_link.group
+      access = invited_group.group_members.find_by(user_id: user_id).try(:access_field)
+
+      # If group member has higher access level we should restrict it
+      # to max allowed access level
+      if access && access > group_link.group_access
+        access = group_link.group_access
+      end
+
+      access
+    end.compact.max
   end
 
   private
@@ -168,6 +188,35 @@ class ProjectTeam
   def fetch_members(level = nil)
     project_members = project.project_members
     group_members = group ? group.group_members : []
+    invited_members = []
+
+    if project.invited_groups.any? && project.allowed_to_share_with_group?
+      project.project_group_links.each do |group_link|
+        invited_group = group_link.group
+        im = invited_group.group_members
+
+        if level
+          int_level = GroupMember.access_level_roles[level.to_s.singularize.titleize]
+
+          # Skip group members if we ask for masters
+          # but max group access is developers
+          next if int_level > group_link.group_access
+
+          # If we ask for developers and max
+          # group access is developers we need to provide
+          # both group master, developers as devs
+          if int_level == group_link.group_access
+            im.where("access_level >= ?)", group_link.group_access)
+          else
+            im.send(level)
+          end
+        end
+
+        invited_members << im
+      end
+
+      invited_members = invited_members.flatten.compact
+    end
 
     if level
       project_members = project_members.send(level)
@@ -175,6 +224,7 @@ class ProjectTeam
     end
 
     user_ids = project_members.pluck(:user_id)
+    user_ids.push(*invited_members.map(&:user_id)) if invited_members.any?
     user_ids.push(*group_members.pluck(:user_id)) if group
 
     User.where(id: user_ids)

app/models/user.rb

@@ -832,7 +832,8 @@ class User < ActiveRecord::Base
   def projects_union
     Gitlab::SQL::Union.new([personal_projects.select(:id),
                             groups_projects.select(:id),
-                            projects.select(:id)])
+                            projects.select(:id),
+                            groups.joins(:shared_projects).select(:project_id)])
   end
 
   def ci_projects_union

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

@@ -50,6 +50,22 @@
       .panel-footer
         = paginate @projects, param_name: 'projects_page', theme: 'gitlab'
 
+    - if @group.shared_projects.any?
+      .panel.panel-default
+        .panel-heading
+          Projects shared with #{@group.name}
+          %span.badge
+            #{@group.shared_projects.count}
+        %ul.well-list
+          - @group.shared_projects.sort_by(&:name).each do |project|
+            %li
+              %strong
+                = link_to project.name_with_namespace, [:admin, project.namespace.becomes(Namespace), project]
+                %span.label.label-gray
+                  = repository_size(project)
+              %span.pull-right.light
+                %span.monospace= project.path_with_namespace + ".git"
+
   .col-md-6
     - if can?(current_user, :admin_group_member, @group)
       .panel.panel-default

app/views/groups/_shared_projects.html.haml

+- if projects.present?
+  .panel.panel-default
+    .panel-heading
+      Projects shared with
+      %strong #{@group.name}
+      (#{projects.count})
+    %ul.well-list
+      - projects.each do |project|
+        %li.project-row
+          = link_to namespace_project_path(project.namespace, project), class: dom_class(project) do
+            %span.namespace-name
+              - if project.namespace
+                = project.namespace.human_name
+                \/
+            %span.project-name
+              = truncate(project.name, length: 25)
+            %span.arrow
+              %i.icon-angle-right

app/views/groups/edit.html.haml

@@ -23,6 +23,15 @@
             %hr
             = link_to 'Remove avatar', group_avatar_path(@group.to_param), data: { confirm: "Group avatar will be removed. Are you sure?"}, method: :delete, class: "btn btn-remove btn-sm remove-avatar"
 
+      .form-group
+        %hr
+        = f.label :share_with_group_lock, class: 'control-label' do
+          Share with group lock
+        .col-sm-10
+          .checkbox
+            = f.check_box :share_with_group_lock
+            %span.descr Prevent sharing a project with another group within this group
+
       .form-actions
         = f.submit 'Save group', class: "btn btn-save"
 

app/views/groups/show.html.haml

@@ -32,6 +32,10 @@
     %li.active
       = link_to "#projects", 'data-toggle' => 'tab' do
         Projects
+    - if @shared_projects.present?
+      %li
+        = link_to "#shared", 'data-toggle' => 'tab' do
+          Shared Projects
 
 - if can?(current_user, :read_group, @group)
   %div{ class: container_class }
@@ -39,6 +43,9 @@
       .tab-pane.active#projects
         = render "projects", projects: @projects
 
+      .tab-pane#shared
+        = render "shared_projects", projects: @shared_projects
+
 - else
   %p.nav-links.no-top
     No projects to show

app/views/layouts/nav/_project_settings.html.haml

@@ -13,6 +13,12 @@
         = icon('pencil-square-o fw')
         %span
           Project Settings
+    - if @project.allowed_to_share_with_group?
+      = nav_link(controller: :group_links) do
+        = link_to namespace_project_group_links_path(@project.namespace, @project), title: "Groups" do
+          = icon('share-square-o fw')
+          %span
+            Groups
     = nav_link(controller: :deploy_keys) do
       = link_to namespace_project_deploy_keys_path(@project.namespace, @project), title: 'Deploy Keys' do
         = icon('key fw')

app/views/projects/group_links/index.html.haml

+- page_title "Groups"
+%h3.page_title Share project with other groups
+%p.light
+  Projects can be stored in only one group at once. However you can share a project with other groups here.
+%hr
+- if @group_links.present?
+  .enabled-groups.panel.panel-default
+    .panel-heading
+      Already shared with
+    %ul.well-list
+      - @group_links.each do |group_link|
+        - group = group_link.group
+        %li
+          .pull-right
+            = link_to namespace_project_group_link_path(@project.namespace, @project, group_link), method: :delete, class: 'btn btn-sm' do
+              %i.icon-remove
+              disable sharing
+          = link_to group do
+            %strong
+              %i.icon-folder-open
+              = group.name
+          %br
+          .light up to #{group_link.human_access}
+
+
+.available-groups
+  %h4
+    Can be shared with
+  %div
+    = form_tag namespace_project_group_links_path(@project.namespace, @project), method: :post, class: 'form-horizontal' do
+      .form-group
+        = label_tag :link_group_id, 'Group', class: 'control-label'
+        .col-sm-10
+          = groups_select_tag(:link_group_id, skip_group: @project.group.try(:path))
+      .form-group
+        = label_tag :link_group_access, 'Max access level', class: 'control-label'
+        .col-sm-10
+          = select_tag :link_group_access, options_for_select(ProjectGroupLink.access_options, ProjectGroupLink.default_access), class: "form-control"
+      .form-actions
+        = submit_tag "Share", class: "btn btn-create"
+

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

+- @project_group_links.each do |group_links|
+  - shared_group = group_links.group
+  - shared_group_users_count = group_links.group.group_members.count
+  .panel.panel-default
+    .panel-heading
+      Shared with
+      %strong #{shared_group.name}
+      group, members with
+      %strong #{group_links.human_access}
+      role (#{shared_group_users_count})
+      - if current_user.can?(:admin_group, shared_group)
+        .panel-head-actions
+          = link_to group_group_members_path(shared_group), class: 'btn btn-sm' do
+            %i.fa.fa-pencil-square-o
+            Edit group members
+    %ul.content-list
+      - shared_group.group_members.order('access_level DESC').limit(20).each do |member|
+        = render 'groups/group_members/group_member', member: member, show_controls: false, show_roles: false
+      - if shared_group_users_count > 20
+        %li
+          and #{shared_group_users_count - 20} more. For full list visit #{link_to 'group members page', group_group_members_path(shared_group)}

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

@@ -18,3 +18,6 @@
 
   - if @group
     = render "group_members", members: @group_members
+
+  - if @project_group_links.any? && @project.allowed_to_share_with_group?
+    = render "shared_group_members"

config/routes.rb

@@ -701,6 +701,8 @@ Rails.application.routes.draw do
           end
         end
 
+        resources :group_links, only: [:index, :create, :destroy], constraints: { id: /\d+/ }
+
         resources :notes, only: [:index, :create, :destroy, :update], constraints: { id: /\d+/ } do
           member do
             delete :delete_attachment

db/migrate/20130711063759_create_project_group_links.rb

+class CreateProjectGroupLinks < ActiveRecord::Migration
+  def change
+    create_table :project_group_links do |t|
+      t.integer :project_id, null: false
+      t.integer :group_id, null: false
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20130820102832_add_access_to_project_group_link.rb

+class AddAccessToProjectGroupLink < ActiveRecord::Migration
+  def change
+    add_column :project_group_links, :group_access, :integer, null: false, default: ProjectGroupLink.default_access
+  end
+end

db/migrate/20150930110012_add_group_share_lock.rb

+class AddGroupShareLock < ActiveRecord::Migration
+  def change
+    add_column :namespaces, :share_with_group_lock, :boolean, default: false
+  end
+end

db/schema.rb

@@ -586,6 +586,7 @@ ActiveRecord::Schema.define(version: 20160309140734) do
     t.string   "type"
     t.string   "description",           default: "",    null: false
     t.string   "avatar"
+    t.boolean  "share_with_group_lock", default: false
   end
 
   add_index "namespaces", ["created_at", "id"], name: "index_namespaces_on_created_at_and_id", using: :btree
@@ -669,6 +670,14 @@ ActiveRecord::Schema.define(version: 20160309140734) do
   add_index "oauth_applications", ["owner_id", "owner_type"], name: "index_oauth_applications_on_owner_id_and_owner_type", using: :btree
   add_index "oauth_applications", ["uid"], name: "index_oauth_applications_on_uid", unique: true, using: :btree
 
+  create_table "project_group_links", force: :cascade do |t|
+    t.integer  "project_id",                null: false
+    t.integer  "group_id",                  null: false
+    t.datetime "created_at"
+    t.datetime "updated_at"
+    t.integer  "group_access", default: 30, null: false
+  end
+
   create_table "project_import_data", force: :cascade do |t|
     t.integer "project_id"
     t.text    "data"
@@ -765,9 +774,9 @@ ActiveRecord::Schema.define(version: 20160309140734) do
     t.string   "type"
     t.string   "title"
     t.integer  "project_id"
-    t.datetime "created_at",                               null: false
-    t.datetime "updated_at",                               null: false
-    t.boolean  "active",                                   null: false
+    t.datetime "created_at"
+    t.datetime "updated_at"
+    t.boolean  "active",                default: false,    null: false
     t.text     "properties"
     t.boolean  "template",              default: false
     t.boolean  "push_events",           default: true

doc/api/projects.md

@@ -619,6 +619,20 @@ Revoking team membership for a user who is not currently a team member is consid
 Please note that the returned JSON currently differs slightly. Thus you should not
 rely on the returned JSON structure.
 
+### Share project with group
+
+Allow to share project with group.
+
+```
+POST /projects/:id/share
+```
+
+Parameters:
+
+- `id` (required) - The ID of a project
+- `group_id` (required) - The ID of a group
+- `group_access` (required) - Level of permissions for sharing
+
 ## Hooks
 
 Also called Project Hooks and Webhooks.

doc/workflow/README.md

@@ -13,6 +13,8 @@
 - [Project forking workflow](forking_workflow.md)
 - [Project users](add-user/add-user.md)
 - [Protected branches](protected_branches.md)
+- [Sharing a project with a group](share_with_group.md)
+- [Share projects with other groups](share_projects_with_other_groups.md)
 - [Web Editor](web_editor.md)
 - [Releases](releases.md)
 - [Milestones](milestones.md)

doc/workflow/share_projects_with_other_groups.md

+# Share Projects with other Groups
+
+In GitLab Enterprise Edition you can share projects with other groups.
+This makes it possible to add a group of users to a project with a single action.
+
+## Groups as collections of users
+
+In GitLab Community Edition groups are used primarily to [create collections of projects](groups.md).
+In GitLab Enterprise Edition you can also take advantage of the fact that groups define collections of _users_, namely the group members.
+
+## Sharing a project with a group of users
+
+The primary mechanism to give a group of users, say 'Engineering', access to a project, say 'Project Acme', in GitLab is to make the 'Engineering' group the owner of 'Project Acme'.
+But what if 'Project Acme' already belongs to another group, say 'Open Source'?
+This is where the (Enterprise Edition only) group sharing feature can be of use.
+
+To share 'Project Acme' with the 'Engineering' group, go to the project settings page for 'Project Acme' and use the left navigation menu to go to the 'Groups' section.
+
+![The 'Groups' section in the project settings screen (Enterprise Edition only)](groups/share_project_with_groups.png)
+
+Now you can add the 'Engineering' group with the maximum access level of your choice.
+After sharing 'Project Acme' with 'Engineering', the project is listed on the group dashboard.
+
+!['Project Acme' is listed as a shared project for 'Engineering'](groups/other_group_sees_shared_project.png)
+
+## Maximum access level
+
+!['Project Acme' is shared with 'Engineering' with a maximum access level of 'Developer'](groups/max_access_level.png)
+
+In the screenshot above, the maximum access level of 'Developer' for members from 'Engineering' means that users with higher access levels in 'Engineering' ('Master' or 'Owner') will only have 'Developer' access to 'Project Acme'.

doc/workflow/share_with_group.md

+# Sharing a project with a group
+
+If you want to share a single project in a group with another group,
+you can do so easily. By setting the permission you can quickly
+give a select group of users access to a project in a restricted manner.
+
+In a project go to the project settings -> groups.
+
+Now you can select a group that you want to share this project with and with
+which maximum access level. Users in that group are able to access this project
+with their set group access level, up to the maximum level that you've set.
+
+![Share a project with a group](share_with_group.png)

features/admin/groups.feature

@@ -21,6 +21,11 @@ Feature: Admin Groups
     When I select user "John Doe" from user list as "Reporter"
     Then I should see "John Doe" in team list in every project as "Reporter"
 
+  Scenario: Shared projects
+    Given group has shared projects
+    When I visit group page
+    Then I should see project shared with group
+
   @javascript
   Scenario: Remove user from group
     Given we have user "John Doe" in group

features/project/group_links.feature

+Feature: Project Group Links
+  Background:
+    Given I sign in as a user
+    And I own project "Shop"
+    And project "Shop" is shared with group "Ops"
+    And project "Shop" is not shared with group "Market"
+    And I visit project group links page
+
+  Scenario: I should see list of groups
+    Then I should see project already shared with group "Ops"
+    Then I should see project is not shared with group "Market"
+
+  @javascript
+  Scenario: I share project with group
+    When I select group "Market" for share
+    Then I should see project is shared with group "Market"

features/project/team_management.feature

@@ -39,3 +39,8 @@ Feature: Project Team Management
     And I click link "Import team from another project"
     And I submit "Website" project for import team
     Then I should see "Mike" in team list as "Reporter"
+
+  Scenario: See all members of projects shared group
+    Given I share project with group "OpenSource"
+    And I visit project "Shop" team page
+    Then I should see "Opensource" group user listing

features/steps/admin/groups.rb

@@ -73,6 +73,21 @@ class Spinach::Features::AdminGroups < Spinach::FeatureSteps
     end
   end
 
+  step 'group has shared projects' do
+    share_link = shared_project.project_group_links.new(group_access: Gitlab::Access::MASTER)
+    share_link.group_id = current_group.id
+    share_link.save!
+  end
+
+  step 'I visit group page' do
+    visit admin_group_path(current_group)
+  end
+
+  step 'I should see project shared with group' do
+    expect(page).to have_content(shared_project.name_with_namespace)
+    expect(page).to have_content "Projects shared with"
+  end
+
   step 'we have user "John Doe" in group' do
     current_group.add_reporter(user_john)
   end
@@ -123,6 +138,10 @@ class Spinach::Features::AdminGroups < Spinach::FeatureSteps
     @group ||= Group.first
   end
 
+  def shared_project
+    @shared_project ||= create(:empty_project)
+  end
+
   def user_john
     @user_john ||= User.find_by(name: "John Doe")
   end

features/steps/project/project_group_links.rb

+class Spinach::Features::ProjectGroupLinks < Spinach::FeatureSteps
+  include SharedAuthentication
+  include SharedProject
+  include SharedPaths
+  include Select2Helper
+
+  step 'I should see project already shared with group "Ops"' do
+    page.within '.enabled-groups' do
+      expect(page).to have_content "Ops"
+    end
+  end
+
+  step 'I should see project is not shared with group "Market"' do
+    page.within '.enabled-groups' do
+      expect(page).not_to have_content "Market"
+    end
+  end
+
+  step 'I select group "Market" for share' do
+    group = Group.find_by(path: 'market')
+    select2(group.id, from: "#link_group_id")
+    select "Master", from: 'link_group_access'
+    click_button "Share"
+  end
+
+  step 'I should see project is shared with group "Market"' do
+    page.within '.enabled-groups' do
+      expect(page).to have_content "Market"
+    end
+  end
+
+  step 'project "Shop" is shared with group "Ops"' do
+    group = create(:group, name: 'Ops')
+    share_link = project.project_group_links.new(group_access: Gitlab::Access::MASTER)
+    share_link.group_id = group.id
+    share_link.save!
+  end
+
+  step 'project "Shop" is not shared with group "Market"' do
+    create(:group, name: 'Market', path: 'market')
+  end
+
+  step 'I visit project group links page' do
+    visit namespace_project_group_links_path(project.namespace, project)
+  end
+
+  def project
+    @project ||= Project.find_by_name "Shop"
+  end
+end

features/steps/project/team_management.rb

@@ -123,4 +123,23 @@ class Spinach::Features::ProjectTeamManagement < Spinach::FeatureSteps
       click_link('Remove user from team')
     end
   end
+
+  step 'I share project with group "OpenSource"' do
+    project = Project.find_by(name: 'Shop')
+    os_group   = create(:group, name: 'OpenSource')
+    create(:project, group: os_group)
+    @os_user1 = create(:user)
+    @os_user2 = create(:user)
+    os_group.add_owner(@os_user1)
+    os_group.add_user(@os_user2, Gitlab::Access::DEVELOPER)
+    share_link = project.project_group_links.new(group_access: Gitlab::Access::MASTER)
+    share_link.group_id = os_group.id
+    share_link.save!
+  end
+
+  step 'I should see "Opensource" group user listing' do
+    expect(page).to have_content("Shared with OpenSource group, members with Master role (2)")
+    expect(page).to have_content(@os_user1.name)
+    expect(page).to have_content(@os_user2.name)
+  end
 end

lib/api/entities.rb

@@ -246,6 +246,10 @@ module API
       end
     end
 
+    class ProjectGroupLink < Grape::Entity
+      expose :id, :project_id, :group_id, :group_access
+    end
+
     class Namespace < Grape::Entity
       expose :id, :path, :kind
     end

lib/api/projects.rb

@@ -290,6 +290,33 @@ module API
         end
       end
 
+      # Share project with group
+      #
+      # Parameters:
+      #   id (required) - The ID of a project
+      #   group_id (required) - The ID of a group
+      #   group_access (required) - Level of permissions for sharing
+      #
+      # Example Request:
+      #   POST /projects/:id/share
+      post ":id/share" do
+        authorize! :admin_project, user_project
+        required_attributes! [:group_id, :group_access]
+
+        unless user_project.allowed_to_share_with_group?
+          return render_api_error!("The project sharing with group is disabled", 400)
+        end
+
+        link = user_project.project_group_links.new
+        link.group_id = params[:group_id]
+        link.group_access = params[:group_access]
+        if link.save
+          present link, with: Entities::ProjectGroupLink
+        else
+          render_api_error!(link.errors.full_messages.first, 409)
+        end
+      end
+
       # Upload a file
       #
       # Parameters:

spec/factories/project_group_links.rb

+FactoryGirl.define do
+  factory :project_group_link do
+    project
+    group
+  end
+end

spec/finders/projects_finder_spec.rb

@@ -17,6 +17,10 @@ describe ProjectsFinder do
       create(:project, :public, group: group, name: 'C', path: 'C')
     end
 
+    let!(:shared_project) do
+      create(:project, :private, name: 'D', path: 'D')
+    end
+
     let(:finder) { described_class.new }
 
     describe 'without a group' do
@@ -56,8 +60,36 @@ describe ProjectsFinder do
       describe 'with a user' do
         subject { finder.execute(user, group: group) }
 
+        describe 'without shared projects' do
           it { is_expected.to eq([public_project, internal_project]) }
         end
+
+        describe 'with shared projects and group membership' do
+          before do
+            group.add_user(user, Gitlab::Access::DEVELOPER)
+
+            shared_project.project_group_links.
+              create(group_access: Gitlab::Access::MASTER, group: group)
+          end
+
+          it do
+            is_expected.to eq([shared_project, public_project, internal_project])
+          end
+        end
+
+        describe 'with shared projects and project membership' do
+          before do
+            shared_project.team.add_user(user, Gitlab::Access::DEVELOPER)
+
+            shared_project.project_group_links.
+              create(group_access: Gitlab::Access::MASTER, group: group)
+          end
+
+          it do
+            is_expected.to eq([shared_project, public_project, internal_project])
+          end
+        end
+      end
     end
   end
 end

spec/models/project_group_link_spec.rb

+require 'spec_helper'
+
+describe ProjectGroupLink do
+  describe "Associations" do
+    it { should belong_to(:group) }
+    it { should belong_to(:project) }
+  end
+
+  describe "Validation" do
+    let!(:project_group_link) { create(:project_group_link) }
+
+    it { should validate_presence_of(:project_id) }
+    it { should validate_uniqueness_of(:group_id).scoped_to(:project_id).with_message(/already shared/) }
+    it { should validate_presence_of(:group_id) }
+    it { should validate_presence_of(:group_access) }
+  end
+end

spec/models/project_team_spec.rb

@@ -67,6 +67,50 @@ describe ProjectTeam, models: true do
     end
   end
 
+  describe :max_invited_level do
+    let(:group) { create(:group) }
+    let(:project) { create(:empty_project) }
+
+    before do
+      project.project_group_links.create(
+        group: group,
+        group_access: Gitlab::Access::DEVELOPER
+      )
+
+      group.add_user(master, Gitlab::Access::MASTER)
+      group.add_user(reporter, Gitlab::Access::REPORTER)
+    end
+
+    it { expect(project.team.max_invited_level(master.id)).to eq(Gitlab::Access::DEVELOPER) }
+    it { expect(project.team.max_invited_level(reporter.id)).to eq(Gitlab::Access::REPORTER) }
+    it { expect(project.team.max_invited_level(nonmember.id)).to be_nil }
+  end
+
+  describe :max_member_access do
+    let(:group) { create(:group) }
+    let(:project) { create(:empty_project) }
+
+    before do
+      project.project_group_links.create(
+        group: group,
+        group_access: Gitlab::Access::DEVELOPER
+      )
+
+      group.add_user(master, Gitlab::Access::MASTER)
+      group.add_user(reporter, Gitlab::Access::REPORTER)
+    end
+
+    it { expect(project.team.max_member_access(master.id)).to eq(Gitlab::Access::DEVELOPER) }
+    it { expect(project.team.max_member_access(reporter.id)).to eq(Gitlab::Access::REPORTER) }
+    it { expect(project.team.max_member_access(nonmember.id)).to be_nil }
+
+    it "does not have an access" do
+      project.namespace.update(share_with_group_lock: true)
+      expect(project.team.max_member_access(master.id)).to be_nil
+      expect(project.team.max_member_access(reporter.id)).to be_nil
+    end
+  end
+
   describe "#human_max_access" do
     it 'returns Master role' do
       user = create(:user)

spec/requests/api/projects_spec.rb

@@ -747,6 +747,42 @@ describe API::API, api: true  do
     end
   end
 
+  describe "POST /projects/:id/share" do
+    let(:group) { create(:group) }
+
+    it "should share project with group" do
+      expect do
+        post api("/projects/#{project.id}/share", user), group_id: group.id, group_access: Gitlab::Access::DEVELOPER
+      end.to change { ProjectGroupLink.count }.by(1)
+
+      expect(response.status).to eq 201
+      expect(json_response['group_id']).to eq group.id
+      expect(json_response['group_access']).to eq Gitlab::Access::DEVELOPER
+    end
+
+    it "should return a 400 error when group id is not given" do
+      post api("/projects/#{project.id}/share", user), group_access: Gitlab::Access::DEVELOPER
+      expect(response.status).to eq 400
+    end
+
+    it "should return a 400 error when access level is not given" do
+      post api("/projects/#{project.id}/share", user), group_id: group.id
+      expect(response.status).to eq 400
+    end
+
+    it "should return a 400 error when sharing is disabled" do
+      project.namespace.update(share_with_group_lock: true)
+      post api("/projects/#{project.id}/share", user), group_id: group.id, group_access: Gitlab::Access::DEVELOPER
+      expect(response.status).to eq 400
+    end
+
+    it "should return a 409 error when wrong params passed" do
+      post api("/projects/#{project.id}/share", user), group_id: group.id, group_access: 1234
+      expect(response.status).to eq 409
+      expect(json_response['message']).to eq 'Group access is not included in the list'
+    end
+  end
+
   describe 'GET /projects/search/:query' do
     let!(:query) { 'query'}
     let!(:search)           { create(:empty_project, name: query, creator_id: user.id, namespace: user.namespace) }