PWA setup along with routes for storing subscriptions and sending push notifications

.gitignore

@@ -4,7 +4,7 @@
 /deps
 /*.ez
 
-/priv/static/
+# /priv/static/
 /rel
 
 node_modules/

assets/src/app.js

@@ -7,6 +7,9 @@ import apolloClient from './apolloClient'
 import Root from './components/Root'
 import ReactGA from 'react-ga'
 
+import * as serviceWorker from './serviceWorker'
+import { subscribeUser } from './subscription'
+
 if (ENV.GOOGLE_ANALYTICS_ID) {
  ReactGA.initialize(ENV.GOOGLE_ANALYTICS_ID)
  ReactGA.pageview(window.location.pathname + window.location.search);
@@ -18,3 +21,7 @@ render(
  </ApolloProvider>,
  document.getElementById('root'),
 )
+
+serviceWorker.register()
+
+subscribeUser() 

assets/src/config.js

@@ -0,0 +1,5 @@
+
+export default {
+ VAPID_KEY: "BItTHe7BXVxVxTWcwu-485CJ3ePaCQcoEbF_Qnlap5H9Do-J-hjnpD0VCcymjEt4JX5BkSHJrLfyGcwZ2XplZLs",
+ API_URL: "http://localhost:4000"
+}

assets/src/serviceWorker.js

@@ -0,0 +1,137 @@
+// This optional code is used to register a service worker.
+// register() is not called by default.
+
+// This lets the app load faster on subsequent visits in production, and gives
+// it offline capabilities. However, it also means that developers (and users)
+// will only see deployed updates on subsequent visits to a page, after all the
+// existing tabs open on the page have been closed, since previously cached
+// resources are updated in the background.
+
+// To learn more about the benefits of this model and instructions on how to
+// opt-in, read https://bit.ly/CRA-PWA
+
+const isLocalhost = Boolean(
+ window.location.hostname === 'localhost' ||
+ // [::1] is the IPv6 localhost address.
+ window.location.hostname === '[::1]' ||
+ // 127.0.0.1/8 is considered localhost for IPv4.
+ window.location.hostname.match(
+ /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
+ )
+ );
+
+ export function register(config) {
+ if ('serviceWorker' in navigator) {
+ // The URL constructor is available in all browsers that support SW.
+ const publicUrl = new URL(process.env.PUBLIC_URL, window.location.href);
+ if (publicUrl.origin !== window.location.origin) {
+ // Our service worker won't work if PUBLIC_URL is on a different origin
+ // from what our page is served on. This might happen if a CDN is used to
+ // serve assets; see https://github.com/facebook/create-react-app/issues/2374
+ return;
+ }
+
+ window.addEventListener('load', () => {
+ const swFileName = process.env.NODE_ENV === 'production' ? 'service-worker.js' : 'custom-sw.js'
+ const swUrl = `${publicUrl.origin}/${swFileName}`;
+
+
+ if (isLocalhost) {
+ // This is running on localhost. Let's check if a service worker still exists or not.
+ checkValidServiceWorker(swUrl, config);
+
+ // Add some additional logging to localhost, pointing developers to the
+ // service worker/PWA documentation.
+ navigator.serviceWorker.ready.then(() => {
+ console.log(
+ 'This web app is being served cache-first by a service ' +
+ 'worker. To learn more, visit https://bit.ly/CRA-PWA'
+ );
+ });
+ } else {
+ // Is not localhost. Just register service worker
+ registerValidSW(swUrl, config);
+ }
+ });
+ }
+ }
+
+ function registerValidSW(swUrl, config) {
+ navigator.serviceWorker
+ .register(swUrl)
+ .then(registration => {
+ registration.onupdatefound = () => {
+ const installingWorker = registration.installing;
+ if (installingWorker == null) {
+ return;
+ }
+ installingWorker.onstatechange = () => {
+ if (installingWorker.state === 'installed') {
+ if (navigator.serviceWorker.controller) {
+ // At this point, the updated precached content has been fetched,
+ // but the previous service worker will still serve the older
+ // content until all client tabs are closed.
+ console.log(
+ 'New content is available and will be used when all ' +
+ 'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
+ );
+
+ // Execute callback
+ if (config && config.onUpdate) {
+ config.onUpdate(registration);
+ }
+ } else {
+ // At this point, everything has been precached.
+ // It's the perfect time to display a
+ // "Content is cached for offline use." message.
+ console.log('Content is cached for offline use.');
+
+ // Execute callback
+ if (config && config.onSuccess) {
+ config.onSuccess(registration);
+ }
+ }
+ }
+ };
+ };
+ })
+ .catch(error => {
+ console.error('Error during service worker registration:', error);
+ });
+ }
+
+ function checkValidServiceWorker(swUrl, config) {
+ // Check if the service worker can be found. If it can't reload the page.
+ fetch(swUrl)
+ .then(response => {
+ // Ensure service worker exists, and that we really are getting a JS file.
+ const contentType = response.headers.get('content-type');
+ if (
+ response.status === 404 ||
+ (contentType != null && contentType.indexOf('javascript') === -1)
+ ) {
+ // No service worker found. Probably a different app. Reload the page.
+ navigator.serviceWorker.ready.then(registration => {
+ registration.unregister().then(() => {
+ window.location.reload();
+ });
+ });
+ } else {
+ // Service worker found. Proceed as normal.
+ registerValidSW(swUrl, config);
+ }
+ })
+ .catch(() => {
+ console.log(
+ 'No internet connection found. App is running in offline mode.'
+ );
+ });
+ }
+
+ export function unregister() {
+ if ('serviceWorker' in navigator) {
+ navigator.serviceWorker.ready.then(registration => {
+ registration.unregister();
+ });
+ }
+ }

assets/src/subscription.js

@@ -0,0 +1,64 @@
+import subscription from "./config"
+
+const VapidKey = subscription.VAPID_KEY
+const APIUrl = subscription.API_URL
+const convertedVapidKey = urlBase64ToUint8Array(VapidKey)
+
+function urlBase64ToUint8Array(base64String) {
+ const padding = "=".repeat((4 - base64String.length % 4) % 4)
+
+ const base64 = (base64String + padding).replace(/\-/g, "+").replace(/_/g, "/")
+
+ const rawData = window.atob(base64)
+ const outputArray = new Uint8Array(rawData.length)
+
+ for (let i = 0; i < rawData.length; ++i) {
+ outputArray[i] = rawData.charCodeAt(i)
+ }
+ return outputArray
+}
+
+function sendSubscription(subscription) {
+ return fetch(`${APIUrl}/webpush/notifications/subscribe`, {
+ method: 'POST',
+ body: JSON.stringify(subscription),
+ headers: {
+ 'Content-Type': 'application/json'
+ }
+ })
+}
+
+export function subscribeUser() {
+ if ('serviceWorker' in navigator) {
+ navigator.serviceWorker.ready.then(function(registration) {
+ if (!registration.pushManager) {
+ console.log('Push manager unavailable.')
+ return
+ }
+
+ registration.pushManager.getSubscription().then(function(existedSubscription) {
+ if (existedSubscription === null) {
+ console.log('No subscription detected, make a request.')
+ registration.pushManager.subscribe({
+ applicationServerKey: convertedVapidKey,
+ userVisibleOnly: true,
+ }).then(function(newSubscription) {
+ console.log('New subscription added.')
+ sendSubscription(newSubscription)
+ }).catch(function(e) {
+ if (Notification.permission !== 'granted') {
+ console.log('Permission was not granted.')
+ } else {
+ console.error('An error ocurred during the subscription process.', e)
+ }
+ })
+ } else {
+ console.log('Existed subscription detected.')
+ }
+ })
+ })
+ .catch(function(e) {
+ console.error('An error ocurred during Service Worker registration.', e)
+ })
+ }
+}

config/config.exs

@@ -26,6 +26,12 @@ config :logger, :console,
 
 config :orcasite, env: Mix.env()
 
+config :web_push_encryption, :vapid_details,
+ subject: "mailto:administrator@example.com",
+ public_key: "BItTHe7BXVxVxTWcwu-485CJ3ePaCQcoEbF_Qnlap5H9Do-J-hjnpD0VCcymjEt4JX5BkSHJrLfyGcwZ2XplZLs",
+ private_key: "v4oOsWwufaMaFelexFj8NjCVAkzMsP2Wni-14wyB_YM"
+
+
 # Import environment specific config. This must remain at the bottom
 # of this file so it overrides the configuration defined above.
 import_config "#{Mix.env}.exs"

config/dev.exs

@@ -11,8 +11,12 @@ config :orcasite, OrcasiteWeb.Endpoint,
  debug_errors: true,
  code_reloader: true,
  check_origin: false,
+ # watchers: [
+ # npm: ["run", "watch",
+ # cd: Path.expand("../assets", __DIR__)
+ # ]]
  watchers: [
- npm: ["run", "watch",
+ node: ["node_modules/webpack-dev-server/bin/webpack-dev-server.js", "--colors", "--stdin", 
  cd: Path.expand("../assets", __DIR__)
  ]]
 

lib/orcasite_web/controllers/webpush_router.ex

@@ -0,0 +1,50 @@
+defmodule OrcasiteWeb.WebpushRouter do
+ use OrcasiteWeb, :controller
+ alias Orcasite.Repo
+
+ defmodule Subscription do
+ use Ecto.Schema
+
+ schema "subscriptions" do
+ field :p256dh, :string
+ field :auth, :string
+ field :endpoint, :string
+ field :expirationTime, :string
+
+ timestamps
+ end
+ end
+
+ def index(conn, params) do
+ send_resp(conn, 200, "world")
+ end
+
+ def postsubsobject(conn, params) do
+ subs = params
+
+ Repo.insert(%Subscription{ p256dh: subs["keys"]["p256dh"], 
+ auth: subs["keys"]["auth"],
+ endpoint: subs["endpoint"],
+ expirationTime: subs["expirationTime"]})
+
+ send_resp(conn, 200, "Subscribed successfully")
+ end
+
+ def sendnotifications(conn, params) do
+ import Ecto.Query
+
+ payload = ~s({"title": "#{params["title"]}", "body": "#{params["body"]}"})
+
+ Repo.all(from(i in Subscription, select: {i.p256dh, i.auth, i.endpoint, i.expirationTime}))
+ |> Enum.each(fn(x) ->
+ IO.puts(elem(x, 1)) 
+ subscription = %{
+ keys: %{p256dh: elem(x, 0), auth: elem(x, 1)},
+ endpoint: elem(x, 2),
+ expirationTime: elem(x, 3)
+ }
+ WebPushEncryption.send_web_push(payload, subscription)
+ end)
+ send_resp(conn, 200, "Sent successfully")
+ end 
+end

lib/orcasite_web/endpoint.ex

@@ -20,7 +20,7 @@ defmodule OrcasiteWeb.Endpoint do
  at: "/",
  from: :orcasite,
  gzip: false,
- only: ~w(css fonts images js favicon.ico robots.txt)
+ only: ~w(css fonts images js favicon.ico robots.txt custom-sw.js service-worker.js)
  )
 
  # Code reloading can be explicitly enabled under the

lib/orcasite_web/router.ex

@@ -29,6 +29,13 @@ defmodule OrcasiteWeb.Router do
  forward "/", Absinthe.Plug.GraphiQL, schema: OrcasiteWeb.Schema, interface: :simple, json_codec: Jason
  end
 
+ scope "/webpush", OrcasiteWeb do
+ pipe_through :api
+ get "/hello", WebpushRouter, :index
+ post "/notifications/subscribe", WebpushRouter, :postsubsobject
+ get "/notifications/payload", WebpushRouter, :sendnotifications
+ end
+
  scope "/", OrcasiteWeb do
  pipe_through :browser # Use the default browser stack
  get("/*page", PageController, :index)

mix.exs

@@ -38,7 +38,7 @@ defmodule Orcasite.Mixfile do
  {:phoenix_ecto, "~> 4.0"},
  {:ecto_sql, "~> 3.0"},
  {:postgrex, ">= 0.0.0"},
- {:phoenix_html, "~> 2.10"},
+ {:phoenix_html, "~> 2.14"},
  {:phoenix_live_reload, "~> 1.0", only: :dev},
  {:gettext, "~> 0.11"},
  {:plug_cowboy, "~> 2.0"},
@@ -48,7 +48,9 @@ defmodule Orcasite.Mixfile do
  {:poison, "~> 3.1.0"}, # JSON parser, works with Absinthe out of the box
  {:logfmt, "~> 3.0"},
  {:geo_postgis, "~> 2.0"},
- {:jason, "~> 1.1"}
+ {:jason, "~> 1.1"},
+ {:web_push_encryption, "~> 0.2"},
+ {:cors_plug, "~> 2.0"}
  ]
  end