Add simple data models

app/models/project.rb

@@ -266,6 +266,9 @@ class Project < ActiveRecord::Base
   has_many :project_deploy_tokens
   has_many :deploy_tokens, through: :project_deploy_tokens
 
+  has_many :project_feature_flags
+  has_many :project_feature_flags_access_tokens
+
   has_one :auto_devops, class_name: 'ProjectAutoDevops'
   has_many :custom_attributes, class_name: 'ProjectCustomAttribute'
 

app/models/project_feature_flag.rb

+class ProjectFeatureFlag < ActiveRecord::Base
+  belongs_to :project
+
+  validates :project, presence: true
+  validates :name,
+    presence: true,
+    length: 2..63,
+    format: {
+      with: Gitlab::Regex.feature_flag_regex,
+      message: Gitlab::Regex.feature_flag_regex_message
+    }
+end

app/models/project_feature_flag_access_token.rb

+class ProjectFeatureFlagAccessToken < ActiveRecord::Base
+  include TokenAuthenticatable
+
+  belongs_to :project
+
+  validates :project, presence: true
+  validates :token, presence: true
+
+  add_authentication_token_field :token
+end

db/migrate/20180626171125_add_feature_flags_to_projects.rb

+class AddFeatureFlagsToProjects < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  def change
+    create_table :project_feature_flags do |t|
+      t.integer :project_id, null: false
+      t.datetime_with_timezone :created_at, null: false
+      t.datetime_with_timezone :updated_at, null: false
+
+      t.string :name, null: false
+      t.text :description
+      t.boolean :active, null: false
+
+      t.foreign_key :projects, column: :project_id, on_delete: :cascade
+
+      t.index [:project_id, :name], unique: true
+    end
+
+    create_table :project_feature_flag_access_tokens do |t|
+      t.integer :project_id, null: false
+      t.string :token, null: false
+
+      t.index [:project_id, :token], unique: true, name: :project_feature_flag_access_token
+
+      t.foreign_key :projects, column: :project_id, on_delete: :cascade
+    end
+  end
+end

lib/gitlab/regex.rb

@@ -71,6 +71,15 @@ module Gitlab
       "Must start with a letter, and cannot end with '-'"
     end
 
+    def feature_flag_regex
+      /\A[a-z]([-a-z0-9]*[a-z0-9])?\z/
+    end
+
+    def feature_flag_regex_message
+      "can contain only lowercase letters, digits, '_' and '-'. " \
+      "Must start with a letter, and cannot end with '-'"
+    end
+
     def build_trace_section_regex
       @build_trace_section_regexp ||= /section_((?:start)|(?:end)):(\d+):([a-zA-Z0-9_.-]+)\r\033\[0K/.freeze
     end