Gitlab Geo initial node discovery

app/models/geo_node.rb

+# == Schema Information
+#
+# Table name: geo_nodes
+#
+#  id                :integer          not null, primary key
+#  host              :string
+#  relative_url_root :string
+#  primary           :boolean
+#
+
+class GeoNode < ActiveRecord::Base
+  default_value_for :primary, false
+  default_value_for :relative_url_root, ''
+
+  validates :host, hostname: true, presence: true, uniqueness: { case_sensitive: false }
+  validates :primary, uniqueness: { message: 'primary node already exists' }, if: :primary
+end

app/validators/hostname_validator.rb

+# HostnameValidator
+#
+# Custom validator for Hostnames.
+#
+# This is similar to an URI validator, but will make sure no schema or
+# path is present, only the domain part.
+#
+class HostnameValidator < ActiveModel::EachValidator
+  def validate_each(record, attribute, value)
+    unless valid_hostname?(value)
+      record.errors.add(attribute, 'must be a valid host')
+    end
+  end
+
+  private
+
+  def valid_hostname?(value)
+    URI.parse("fake://#{value}").hostname == value
+  end
+end

db/migrate/20160112174440_create_geo_nodes.rb

+class CreateGeoNodes < ActiveRecord::Migration
+  def change
+    create_table :geo_nodes do |t|
+      t.string :host
+      t.string :relative_url_root
+      t.boolean :primary
+    end
+  end
+end

db/schema.rb

@@ -400,6 +400,12 @@ ActiveRecord::Schema.define(version: 20160119170055) do
 
   add_index "forked_project_links", ["forked_to_project_id"], name: "index_forked_project_links_on_forked_to_project_id", unique: true, using: :btree
 
+  create_table "geo_nodes", force: :cascade do |t|
+    t.string  "host"
+    t.string  "relative_url_root"
+    t.boolean "primary"
+  end
+
   create_table "git_hooks", force: :cascade do |t|
     t.string   "force_push_regex"
     t.string   "delete_branch_regex"

lib/gitlab/geo.rb

+module Gitlab
+  module Geo
+    def self.enabled?
+      GeoNode.exists?
+    end
+
+    def self.current_node
+      GeoNode.find_by(host: Gitlab.config.gitlab.host, relative_url_root: Gitlab.config.gitlab.relative_url_root)
+    end
+  end
+end