Update example with firebase auth

examples/with-firebase-authentication/README.md

@@ -24,11 +24,21 @@ cd with-firebase-authentication
 Set up firebase:
 
 - Create a project at the [Firebase console](https://console.firebase.google.com/).
-- Get your account credentials from the Firebase console at _settings>service accounts_, where you can click on _generate new private key_ and download the credentials as a json file. It will contain keys such as `project_id`, `client_email` and `client id`. Now copy them into your project in the `credentials/server.js` file.
-- Get your authentication credentials from the Firebase console under _authentication>users>web setup_. It will include keys like `apiKey`, `authDomain` and `databaseUrl` and it goes into your project in `credentials/client.js`.
-- Copy the `databaseUrl` key you got in the last step into `server.js` in the corresponding line.
-- Back at the Firebase web console, go to _authentication>signup method_ and select _Google_.
-- Create a database in the "Database" tab and select the realtime database. Then go to "rules" and set up your write, read rules. Examples can be found here: https://firebase.google.com/docs/database/security/quickstart#sample-rules
+- Get your account credentials from the Firebase console at _project settings>service accounts_, where you can click on _generate new private key_ and download the credentials as a json file. It will contain keys such as `project_id`, `client_email` and `client id`. Now copy them into your project in the `credentials/server.js` file.
+- Get your authentication credentials from the Firebase console under _project settings>general>your apps_ Add a new web app if you don't already have one. Under _Firebase SDK snippet_ choose _Config_ to get the configuration as JSON. It will include keys like `apiKey`, `authDomain` and `databaseUrl` and it goes into your project in `credentials/client.js`.
+- Back at the Firebase web console, go to _Authentication>Sign-in method_ and enable _Google_.
+- Create a database in the "Database" tab and select Firestore. Then go to "rules" and set up your write, read rules to this:
+
+```
+// Allow read/write access on all documents to any user signed in to the application
+service cloud.firestore {
+  match /databases/{database}/documents {
+    match /{document=**} {
+      allow read, write: if request.auth.uid != null;
+    }
+  }
+}
+```
 
 Install it and run:
 

examples/with-firebase-authentication/server.js

@@ -12,8 +12,7 @@ const handle = app.getRequestHandler()
 
 const firebase = admin.initializeApp(
   {
-    credential: admin.credential.cert(require('./credentials/server')),
-    databaseURL: '' // TODO database URL goes here
+    credential: admin.credential.cert(require('./credentials/server'))
   },
   'server'
 )
@@ -26,7 +25,7 @@ app.prepare().then(() => {
     session({
       secret: 'geheimnis',
       saveUninitialized: true,
-      store: new FileStore({ path: '/tmp/sessions', secret: 'geheimnis' }),
+      store: new FileStore({ secret: 'geheimnis' }),
       resave: false,
       rolling: true,
       httpOnly: true,