Added group-create.js script with example

firebase/scripts/group-create.js

@@ -0,0 +1,54 @@
+const admin = require('firebase-admin');
+
+var serviceAccount = require("../your-firebase-sdk-config-file.json");
+
+admin.initializeApp({
+    credential: admin.credential.cert(serviceAccount),
+    databaseURL: "https://your-firebase-project.firebaseio.com"
+});
+
+const db = admin.firestore();
+
+(async () => {
+    try {
+
+        // Get all users of the database
+        const users = await db.collection('/users').listDocuments();
+        const members = [];
+        for (let i = 0; i < users.length; i++) {
+            members[i] = (await users[i].get()).data().uid;
+        }
+
+        // create a new 'dev' group
+        const group = await db.collection('/groups').add({
+            'abbreviation': 'DV',
+            'color': 'fcba03',
+            'name': 'dev',
+            'members': members
+        });
+
+        // add all users to the 'dev' group
+        for (let i = 0; i < users.length; i++) {
+            const joinedGroups = (await users[i].get()).data().joinedGroups;
+            joinedGroups.push(group.id);
+            users[i].update({
+                'joinedGroups' : joinedGroups
+            });
+        }
+
+        // create a general channel
+        db.collection('/groups')
+            .doc(group.id)
+            .collection('/channels')
+            .add({
+                'name': "general",
+                'type': "TOPIC",
+                'visibility': "OPEN"
+            })
+
+        console.log(`Group with id ${group.id} created`);
+
+    } catch (e) {
+        console.log(e);
+    }
+})();