created channel for action cable and friendship relationship in database

db/migrate/20180827151325_create_connections.rb

@@ -0,0 +1,8 @@
+class CreateConnections < ActiveRecord::Migration[5.2]
+  def change
+    create_table :connections do |t|
+      t.references :user, foreign_key: true, index: true
+      t.references :contact, foreign_key: { to_table: :users }, index: true
+    end
+  end
+end

db/schema.rb

@@ -10,11 +10,18 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2018_08_27_143700) do
+ActiveRecord::Schema.define(version: 2018_08_27_151325) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
+  create_table "connections", force: :cascade do |t|
+    t.bigint "user_id"
+    t.bigint "contact_id"
+    t.index ["contact_id"], name: "index_connections_on_contact_id"
+    t.index ["user_id"], name: "index_connections_on_user_id"
+  end
+
   create_table "users", force: :cascade do |t|
     t.string "email", default: "", null: false
     t.string "encrypted_password", default: "", null: false
@@ -27,4 +34,6 @@ ActiveRecord::Schema.define(version: 2018_08_27_143700) do
     t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
   end
 
+  add_foreign_key "connections", "users"
+  add_foreign_key "connections", "users", column: "contact_id"
 end