3 files changed, 196 insertions, 0 deletions
diff --git a/app/javascript/flavours/glitch/actions/push_notifications/index.js b/app/javascript/flavours/glitch/actions/push_notifications/index.js
new file mode 100644
index 000000000..2ffec500a
--- /dev/null
+++ b/app/javascript/flavours/glitch/actions/push_notifications/index.js
@@ -0,0 +1,23 @@
+import {
+  SET_BROWSER_SUPPORT,
+  SET_SUBSCRIPTION,
+  CLEAR_SUBSCRIPTION,
+  SET_ALERTS,
+  setAlerts,
+} from './setter';
+import { register, saveSettings } from './registerer';
+
+export {
+  SET_BROWSER_SUPPORT,
+  SET_SUBSCRIPTION,
+  CLEAR_SUBSCRIPTION,
+  SET_ALERTS,
+  register,
+};
+
+export function changeAlerts(path, value) {
+  return dispatch => {
+    dispatch(setAlerts(path, value));
+    dispatch(saveSettings());
+  };
+}
diff --git a/app/javascript/flavours/glitch/actions/push_notifications/registerer.js b/app/javascript/flavours/glitch/actions/push_notifications/registerer.js
new file mode 100644
index 000000000..8fdb239f7
--- /dev/null
+++ b/app/javascript/flavours/glitch/actions/push_notifications/registerer.js
@@ -0,0 +1,139 @@
+import api from 'flavours/glitch/util/api';
+import { pushNotificationsSetting } from 'flavours/glitch/util/settings';
+import { setBrowserSupport, setSubscription, clearSubscription } from './setter';
+
+// Taken from https://www.npmjs.com/package/web-push
+const 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;
+};
+
+const getApplicationServerKey = () => document.querySelector('[name="applicationServerKey"]').getAttribute('content');
+
+const getRegistration = () => navigator.serviceWorker.ready;
+
+const getPushSubscription = (registration) =>
+  registration.pushManager.getSubscription()
+    .then(subscription => ({ registration, subscription }));
+
+const subscribe = (registration) =>
+  registration.pushManager.subscribe({
+    userVisibleOnly: true,
+    applicationServerKey: urlBase64ToUint8Array(getApplicationServerKey()),
+  });
+
+const unsubscribe = ({ registration, subscription }) =>
+  subscription ? subscription.unsubscribe().then(() => registration) : registration;
+
+const sendSubscriptionToBackend = (getState, subscription, me) => {
+  const params = { subscription };
+
+  if (me) {
+    const data = pushNotificationsSetting.get(me);
+    if (data) {
+      params.data = data;
+    }
+  }
+
+  return api(getState).post('/api/web/push_subscriptions', params).then(response => response.data);
+};
+
+// Last one checks for payload support: https://web-push-book.gauntface.com/chapter-06/01-non-standards-browsers/#no-payload
+const supportsPushNotifications = ('serviceWorker' in navigator && 'PushManager' in window && 'getKey' in PushSubscription.prototype);
+
+export function register () {
+  return (dispatch, getState) => {
+    dispatch(setBrowserSupport(supportsPushNotifications));
+    const me = getState().getIn(['meta', 'me']);
+
+    if (supportsPushNotifications) {
+      if (!getApplicationServerKey()) {
+        console.error('The VAPID public key is not set. You will not be able to receive Web Push Notifications.');
+        return;
+      }
+
+      getRegistration()
+        .then(getPushSubscription)
+        .then(({ registration, subscription }) => {
+          if (subscription !== null) {
+            // We have a subscription, check if it is still valid
+            const currentServerKey = (new Uint8Array(subscription.options.applicationServerKey)).toString();
+            const subscriptionServerKey = urlBase64ToUint8Array(getApplicationServerKey()).toString();
+            const serverEndpoint = getState().getIn(['push_notifications', 'subscription', 'endpoint']);
+
+            // If the VAPID public key did not change and the endpoint corresponds
+            // to the endpoint saved in the backend, the subscription is valid
+            if (subscriptionServerKey === currentServerKey && subscription.endpoint === serverEndpoint) {
+              return subscription;
+            } else {
+              // Something went wrong, try to subscribe again
+              return unsubscribe({ registration, subscription }).then(subscribe).then(
+                subscription => sendSubscriptionToBackend(getState, subscription, me));
+            }
+          }
+
+          // No subscription, try to subscribe
+          return subscribe(registration).then(
+            subscription => sendSubscriptionToBackend(getState, subscription, me));
+        })
+        .then(subscription => {
+          // If we got a PushSubscription (and not a subscription object from the backend)
+          // it means that the backend subscription is valid (and was set during hydration)
+          if (!(subscription instanceof PushSubscription)) {
+            dispatch(setSubscription(subscription));
+            if (me) {
+              pushNotificationsSetting.set(me, { alerts: subscription.alerts });
+            }
+          }
+        })
+        .catch(error => {
+          if (error.code === 20 && error.name === 'AbortError') {
+            console.warn('Your browser supports Web Push Notifications, but does not seem to implement the VAPID protocol.');
+          } else if (error.code === 5 && error.name === 'InvalidCharacterError') {
+            console.error('The VAPID public key seems to be invalid:', getApplicationServerKey());
+          }
+
+          // Clear alerts and hide UI settings
+          dispatch(clearSubscription());
+          if (me) {
+            pushNotificationsSetting.remove(me);
+          }
+
+          return getRegistration()
+            .then(getPushSubscription)
+            .then(unsubscribe);
+        })
+        .catch(console.warn);
+    } else {
+      console.warn('Your browser does not support Web Push Notifications.');
+    }
+  };
+}
+
+export function saveSettings() {
+  return (_, getState) => {
+    const state = getState().get('push_notifications');
+    const subscription = state.get('subscription');
+    const alerts = state.get('alerts');
+    const data = { alerts };
+
+    api(getState).put(`/api/web/push_subscriptions/${subscription.get('id')}`, {
+      data,
+    }).then(() => {
+      const me = getState().getIn(['meta', 'me']);
+      if (me) {
+        pushNotificationsSetting.set(me, data);
+      }
+    }).catch(console.warn);
+  };
+}
diff --git a/app/javascript/flavours/glitch/actions/push_notifications/setter.js b/app/javascript/flavours/glitch/actions/push_notifications/setter.js
new file mode 100644
index 000000000..5561766bf
--- /dev/null
+++ b/app/javascript/flavours/glitch/actions/push_notifications/setter.js
@@ -0,0 +1,34 @@
+export const SET_BROWSER_SUPPORT = 'PUSH_NOTIFICATIONS_SET_BROWSER_SUPPORT';
+export const SET_SUBSCRIPTION = 'PUSH_NOTIFICATIONS_SET_SUBSCRIPTION';
+export const CLEAR_SUBSCRIPTION = 'PUSH_NOTIFICATIONS_CLEAR_SUBSCRIPTION';
+export const SET_ALERTS = 'PUSH_NOTIFICATIONS_SET_ALERTS';
+
+export function setBrowserSupport (value) {
+  return {
+    type: SET_BROWSER_SUPPORT,
+    value,
+  };
+}
+
+export function setSubscription (subscription) {
+  return {
+    type: SET_SUBSCRIPTION,
+    subscription,
+  };
+}
+
+export function clearSubscription () {
+  return {
+    type: CLEAR_SUBSCRIPTION,
+  };
+}
+
+export function setAlerts (path, value) {
+  return dispatch => {
+    dispatch({
+      type: SET_ALERTS,
+      path,
+      value,
+    });
+  };
+}