From 3f075c7794ca7cc6e3c566591e9929859c6c325c Mon Sep 17 00:00:00 2001
From: Eugen Rochko <eugen@zeonfederated.com>
Date: Sun, 29 Jan 2017 01:30:32 +0100
Subject: [PATCH] API for apps to register for push notifications

---
 Gemfile                                       |  1 +
 Gemfile.lock                                  |  7 +++++
 app/controllers/api/v1/devices_controller.rb  | 18 ++++++++++++
 app/models/device.rb                          |  7 +++++
 app/services/notify_service.rb                |  5 ++++
 .../send_push_notification_service.rb         | 28 +++++++++++++++++++
 app/workers/push_notification_worker.rb       | 11 ++++++++
 config/routes.rb                              |  3 ++
 db/migrate/20170129000348_create_devices.rb   | 13 +++++++++
 db/schema.rb                                  | 11 +++++++-
 spec/fabricators/device_fabricator.rb         |  3 ++
 spec/fabricators/domain_block_fabricator.rb   |  2 +-
 spec/models/device_spec.rb                    |  5 ++++
 13 files changed, 112 insertions(+), 2 deletions(-)
 create mode 100644 app/controllers/api/v1/devices_controller.rb
 create mode 100644 app/models/device.rb
 create mode 100644 app/services/send_push_notification_service.rb
 create mode 100644 app/workers/push_notification_worker.rb
 create mode 100644 db/migrate/20170129000348_create_devices.rb
 create mode 100644 spec/fabricators/device_fabricator.rb
 create mode 100644 spec/models/device_spec.rb

diff --git a/Gemfile b/Gemfile
index fb9a11ba..4472f330 100644
--- a/Gemfile
+++ b/Gemfile
@@ -50,6 +50,7 @@ gem 'pg_search'
 gem 'simple-navigation'
 gem 'statsd-instrument'
 gem 'ruby-oembed', require: 'oembed'
+gem 'fcm'
 
 gem 'react-rails'
 gem 'browserify-rails'
diff --git a/Gemfile.lock b/Gemfile.lock
index 5361b2a0..bfed2907 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -127,6 +127,9 @@ GEM
     execjs (2.7.0)
     fabrication (2.15.2)
     fast_blank (1.0.0)
+    fcm (0.0.2)
+      httparty
+      json
     font-awesome-rails (4.6.3.1)
       railties (>= 3.2, < 5.1)
     fuubar (2.1.1)
@@ -160,6 +163,8 @@ GEM
       domain_name (~> 0.5)
     http-form_data (1.0.1)
     http_parser.rb (0.6.0)
+    httparty (0.14.0)
+      multi_xml (>= 0.5.2)
     httplog (0.3.2)
       colorize
     i18n (0.7.0)
@@ -207,6 +212,7 @@ GEM
     mini_portile2 (2.1.0)
     minitest (5.10.1)
     multi_json (1.12.1)
+    multi_xml (0.6.0)
     nio4r (1.2.1)
     nokogiri (1.7.0.1)
       mini_portile2 (~> 2.1.0)
@@ -434,6 +440,7 @@ DEPENDENCIES
   dotenv-rails
   fabrication
   fast_blank
+  fcm
   font-awesome-rails
   fuubar
   goldfinger
diff --git a/app/controllers/api/v1/devices_controller.rb b/app/controllers/api/v1/devices_controller.rb
new file mode 100644
index 00000000..c565e972
--- /dev/null
+++ b/app/controllers/api/v1/devices_controller.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+class Api::V1::DevicesController < ApiController
+  before_action -> { doorkeeper_authorize! :read }
+  before_action :require_user!
+
+  respond_to :json
+
+  def register
+    Device.where(account: current_account, registration_id: params[:registration_id]).first_or_create!(account: current_account, registration_id: params[:registration_id])
+    render_empty
+  end
+
+  def unregister
+    Device.where(account: current_account, registration_id: params[:registration_id]).delete_all
+    render_empty
+  end
+end
diff --git a/app/models/device.rb b/app/models/device.rb
new file mode 100644
index 00000000..2782a7f3
--- /dev/null
+++ b/app/models/device.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class Device < ApplicationRecord
+  belongs_to :account
+
+  validates :account, :registration_id, presence: true
+end
diff --git a/app/services/notify_service.rb b/app/services/notify_service.rb
index 1ec36637..d1504cad 100644
--- a/app/services/notify_service.rb
+++ b/app/services/notify_service.rb
@@ -10,6 +10,7 @@ class NotifyService < BaseService
 
     create_notification
     send_email if email_enabled?
+    send_push_notification
   rescue ActiveRecord::RecordInvalid
     return
   end
@@ -57,6 +58,10 @@ class NotifyService < BaseService
     NotificationMailer.send(@notification.type, @recipient, @notification).deliver_later
   end
 
+  def send_push_notification
+    PushNotificationWorker.perform_async(@notification.id)
+  end
+
   def email_enabled?
     @recipient.user.settings.notification_emails[@notification.type]
   end
diff --git a/app/services/send_push_notification_service.rb b/app/services/send_push_notification_service.rb
new file mode 100644
index 00000000..802614fc
--- /dev/null
+++ b/app/services/send_push_notification_service.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+class SendPushNotificationService < BaseService
+  def call(notification)
+  	return if ENV['FCM_API_KEY'].blank?
+
+  	devices = Device.where(account: notification.account).pluck(:registration_id)
+  	fcm     = FCM.new(ENV['FCM_API_KEY'])
+
+  	response = fcm.send(devices, data: { notification_id: notification.id }, collapse_key: :notifications, priority: :high)
+  	handle_response(response)
+  end
+
+  private
+
+  def handle_response(response)
+    update_canonical_ids(response[:canonical_ids]) if response[:canonical_ids]
+    remove_bad_ids(response[:not_registered_ids])  if response[:not_registered_ids]
+  end
+
+  def update_canonical_ids(ids)
+  	ids.each { |pair| Device.find_by(registration_id: pair[:old]).update(registration_id: pair[:new]) }
+  end
+
+  def remove_bad_ids(bad_ids)
+  	Device.where(registration_id: bad_ids).delete_all
+  end
+end
diff --git a/app/workers/push_notification_worker.rb b/app/workers/push_notification_worker.rb
new file mode 100644
index 00000000..a61d0e34
--- /dev/null
+++ b/app/workers/push_notification_worker.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class PushNotificationWorker
+  include Sidekiq::Worker
+
+  def perform(notification_id)
+    SendPushNotificationService.new.call(Notification.find(notification_id))
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+end
diff --git a/config/routes.rb b/config/routes.rb
index 87f35770..bce345f2 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -118,6 +118,9 @@ Rails.application.routes.draw do
       resources :blocks,     only: [:index]
       resources :favourites, only: [:index]
 
+      post '/devices/register',   to: 'devices#register', as: :register_device
+      post '/devices/unregister', to: 'devices#unregister', as: :unregister_device
+
       resources :follow_requests, only: [:index] do
         member do
           post :authorize
diff --git a/db/migrate/20170129000348_create_devices.rb b/db/migrate/20170129000348_create_devices.rb
new file mode 100644
index 00000000..bf8f5fc6
--- /dev/null
+++ b/db/migrate/20170129000348_create_devices.rb
@@ -0,0 +1,13 @@
+class CreateDevices < ActiveRecord::Migration[5.0]
+  def change
+    create_table :devices do |t|
+      t.integer :account_id, null: false
+      t.string :registration_id, null: false, default: ''
+
+      t.timestamps
+    end
+
+    add_index :devices, :registration_id
+    add_index :devices, :account_id
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 7a7fea86..448a7b86 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170127165745) do
+ActiveRecord::Schema.define(version: 20170129000348) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -54,6 +54,15 @@ ActiveRecord::Schema.define(version: 20170127165745) do
     t.index ["account_id", "target_account_id"], name: "index_blocks_on_account_id_and_target_account_id", unique: true, using: :btree
   end
 
+  create_table "devices", force: :cascade do |t|
+    t.integer  "account_id",                   null: false
+    t.string   "registration_id", default: "", null: false
+    t.datetime "created_at",                   null: false
+    t.datetime "updated_at",                   null: false
+    t.index ["account_id"], name: "index_devices_on_account_id", using: :btree
+    t.index ["registration_id"], name: "index_devices_on_registration_id", using: :btree
+  end
+
   create_table "domain_blocks", force: :cascade do |t|
     t.string   "domain",       default: "", null: false
     t.datetime "created_at",                null: false
diff --git a/spec/fabricators/device_fabricator.rb b/spec/fabricators/device_fabricator.rb
new file mode 100644
index 00000000..02b24e8b
--- /dev/null
+++ b/spec/fabricators/device_fabricator.rb
@@ -0,0 +1,3 @@
+Fabricator(:device) do
+  registration_id "12345678"
+end
diff --git a/spec/fabricators/domain_block_fabricator.rb b/spec/fabricators/domain_block_fabricator.rb
index 540ddcac..563a0f65 100644
--- a/spec/fabricators/domain_block_fabricator.rb
+++ b/spec/fabricators/domain_block_fabricator.rb
@@ -1,3 +1,3 @@
 Fabricator(:domain_block) do
-  domain "MyString"
+  domain "example.com"
 end
diff --git a/spec/models/device_spec.rb b/spec/models/device_spec.rb
new file mode 100644
index 00000000..f56fbf97
--- /dev/null
+++ b/spec/models/device_spec.rb
@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Device, type: :model do
+
+end