docs(functions-general): improve documentation

Author: rams23

packages/functions/src/load-balancing/onConnectionDelete.ts

@@ -12,9 +12,7 @@ const logger = functions.logger;
  *
  * The proper document of Firestore, representing that RTDB instance, is updated incrementing by -1
  *
- * Next, an RTDB query is performed to look for the online users for those games.
- * If more than zero were found, it means there is still someone in the game
- * Otherwise, we can move the game from RTDB back to Firestore, for each game.
+ * Cards that are locked by the disconnected user are unlocked
  */
 
 export async function handler(snapshot: functions.database.DataSnapshot, context: functions.EventContext, rtdbId:string, rtdbUrl:string) {

packages/functions/src/load-balancing/scheduledMoveGame.ts

@@ -8,6 +8,11 @@ const logger = functions.logger;
 
 export const DAY_IN_MILLIS = 24 * 60 * 60 * 1000;
 
+/**
+ * Scheduled job to move stale games from the real time database to Firestore.
+ *
+ * A game is stale if no one connects to it for a day.
+ */
 export const moveGamesJob = async () => {
   const lastActiveGamesDate = new Date(Date.now() - DAY_IN_MILLIS);
 

packages/functions/src/load-balancing/selectBestRTDBInstance.ts

@@ -6,39 +6,6 @@ import {getDatabase, PROJECT_ID} from "../utils/rtdb";
 import {Game} from "../models/Game";
 const logger = functions.logger;
 
-/*const getNextRTDBInstanceNum = async (): Promise<number> => {
-  const res = await axios.get(`https://firebasedatabase.googleapis.com/v1beta/projects/${PROJECT_ID}/locations/-/instances?pageSize=100`, {
-    headers: {
-      'Authorization': `Bearer `,
-    },
-  })
-  const instances = res.data.instances as any[];
-  return instances.length;
-}
-
-const createRTDBInstance = async (databaseId: string) => {
-  await axios.get(`https://firebasedatabase.googleapis.com/v1beta/projects/${PROJECT_ID}/locations/${RTDB_LOCATION}/instances?database_id=${databaseId}`, {
-    headers: {
-      'Authorization': `Bearer `,
-    },
-  })
-}
-
-const createNewRTDBInstance = async () => {
-  const nextNum = await getNextRTDBInstanceNum();
-  const newRTDBInstanceName = getRTDBInstanceName(nextNum);
-  await createRTDBInstance(newRTDBInstanceName);
-  await db.collection(FirebaseCollection.RTDBInstances).doc(newRTDBInstanceName).set({
-    createdAt: FieldValue.serverTimestamp(),
-    connectionsCount: 0,
-  } as RTDBInstance)
-  admin.app().database(`https://secondary_db_url.firebaseio.com`)
-
-  return newRTDBInstanceName;
-}
-
- */
-
 /**
  * API to effectively balance the game load by selected the best RTDB instance, in terms of minimum number connections (tabs, browsers, devices, ...).
  * It needs a "gameId" as url parameter and can be called only by authenticated users.

packages/functions/src/load-balancing/utils.ts

@@ -10,7 +10,6 @@ const logger = functions.logger;
 
 type CardStateEntity = CardState & {id: string};
 
-// TODO refactor this
 function unlockAndZIndexNormalize(cardsSnap: admin.database.DataSnapshot) {
   let newCards: {[key: string]: CardState} | null;
 

packages/functions/src/utils/rtdb.ts

@@ -2,8 +2,12 @@ import * as admin from "firebase-admin";
 
 export const PROJECT_ID = JSON.parse(process.env.FIREBASE_CONFIG!).projectId;
 
-
-export function getDatabase( url: string) {
+/**
+ * Returns the database management object given the url.
+ *
+ * @param url the database complete url
+ */
+export function getDatabase( url: string): admin.database.Database {
   const app = admin.apps.find(a => a?.name === url);
 
   if (app) {