I have following sample function from this tutorial: Asynchronous Programming (I Promise!) with Cloud Functions for Firebase - Firecasts
exports.emailEmployeeReport = functions.database
.ref('/employees/${eid}/reports/${rid}')
.onWrite(event => {
const eid = event.params.eid;
const report = event.data.val().report;
const root = event.data.ref.root;
const mgr_promise = root.child(`/employees/${eid}/manager`).once('value');
const then_promise = mgr_promise.then(snap => {
const mgr_id = snap.val();
const email_promise = root.child(`/employees/${mgr_id}/email`).once('value');
return email_promise;
}).catch(reason => {
// Handle the error
console.log(reason);
});;
const then_promise2 = then_promise.then(snap => {
const email = snap.val();
const emailReportPromise = sendReportEmail(email, report);
return emailReportPromise;
}).catch(reason => {
// Handle the error
console.log(reason);
});
return then_promise2;
});
var sendReportEmail = function (email, report) {
const myFirstPromise = new Promise((resolve, reject) => {
// do something asynchronous which eventually calls either:
//
setTimeout(function () {
try {
var someValue = "sendReportEmail";
console.log(someValue);
// fulfilled
resolve(someValue);
}
catch (ex) {
// rejected
reject(ex);
}
}, 2000);
});
return myFirstPromise;
}
once I run firebase deploy command, eventually I am getting following error:
functions[emailEmployeeReport]: Deploy Error: Failed to configure
trigger
providers/google.firebase.database/eventTypes/ref.write#firebaseio.com
(emailEmployeeReport)
I also have a simple hello-world method and a similar trigger method, and they deploy fine.
Am I missing something here?
The syntax for wildcards in the database reference does not have "$".
Try the following:
exports.emailEmployeeReport = functions.database
.ref('/employees/{eid}/reports/{rid}')
Related
I have the following Function that:
Listens for document (text message) creation
Grab IDs of members of a group chat
Get the FCM Tokens for each member
With a for-loop, send messages to group members
exports.sendChatMessage = functions.firestore
.document("chats/{mealID}/messages/{messageID}")
.onCreate((snap, context) => {
const data = snap.data();
const mealID = context.params.mealID;
const senderID = data.senderID;
const senderName = data.senderName;
const messageContent = data.content;
var docRef = db.collection("chats").doc(mealID);
docRef
.get()
.then((doc) => {
if (doc.exists) {
const docData = doc.data();
const mealName = docData.name;
const userStatus = docData.userStatus;
var users = docData.to;
var eligibleUsers = users.filter(
(user) => userStatus[user] == "accepted"
);
eligibleUsers.push(docData.from);
// get fcmTokens from eligibleUsers and send the messagme
db.collection("users")
.where("uid", "in", eligibleUsers)
.get()
.then((snapshot) => {
var fcmTokens = [];
var thumbnailPicURL = "";
// get thumbnailpic of the sender and collect fcmTokens
snapshot.forEach((doc) => {
if (doc.data().uid == senderID) {
thumbnailPicURL =
doc.data().thumbnailPicURL == null
? "https://i.imgur.com/8wSudUk.png"
: doc.data().thumbnailPicURL;
} else {
fcmTokens.push(doc.data().fcmToken);
}
});
// send the message fcmTokens
fcmTokens.forEach((token) => {
if (token != "") {
const fcmMessage = {
message: {
token: token,
notification: {
title: mealName,
body: senderName + ": " + messageContent,
image: thumbnailPicURL,
},
apns: {
payload: {
aps: {
category: "MESSAGE_RECEIVED",
},
MEAL_ID: mealID,
},
},
},
};
tokenManger.sendFcmMessage(fcmMessage);
}
});
return true;
});
} else {
// doc.data() will be undefined in this case
console.log("No such document!");
return false;
}
})
.catch((error) => {
console.log("Error getting document:", error);
return false;
});
return true;
});
My send function comes from a helper file that uses the HTTP V1 protocol to build the send-request:
const { google } = require("googleapis");
const https = require("https");
const MESSAGING_SCOPE = "https://www.googleapis.com/auth/firebase.messaging";
const SCOPES = [MESSAGING_SCOPE];
const PROJECT_ID = MY_PROJECT_ID;
const HOST = "fcm.googleapis.com";
const PATH = "/v1/projects/" + PROJECT_ID + "/messages:send";
exports.getAccessToken = () => {
return new Promise(function (resolve, reject) {
const key = require("./service-account.json");
var jwtClient = new google.auth.JWT(
key.client_email,
null,
key.private_key,
SCOPES,
null
);
jwtClient.authorize(function (err, tokens) {
if (err) {
reject(err);
return;
}
resolve(tokens.access_token);
});
});
};
//send message
exports.sendFcmMessage = (fcmMessage) => {
this.getAccessToken().then(function (accessToken) {
var options = {
hostname: HOST,
path: PATH,
method: "POST",
headers: {
Authorization: "Bearer " + accessToken,
},
// … plus the body of your notification or data message
};
var request = https.request(options, function (resp) {
resp.setEncoding("utf8");
resp.on("data", function (data) {
console.log("Message sent to Firebase for delivery, response:");
console.log(data);
});
});
request.on("error", function (err) {
console.log("Unable to send message to Firebase");
console.log(err);
});
request.write(JSON.stringify(fcmMessage));
request.end();
});
};
It worked all fine in the emulator but once deployed, there're significant delays (~3 mins):
I also noticed that the console says the cloud function finishes execution BEFORE sendFcmMessage logs success messages.
I did some research online, it appears that it might have something to do with the usage of Promise but I wasn't sure if that's the sole reason or it has something to do with my for-loop.
The Problem
To summarize the issue, you are creating "floating promises" or starting other asynchronous tasks (like in sendFcmMessage) where you aren't returning a promise because they use callbacks instead.
In a deployed function, as soon as the function returns its result or the Promise chain resolves, all further actions should be treated as if they will never be executed as documented here. An "inactive" function might be terminated at any time, is severely throttled and any network calls you make (like setting data in database or calling out to FCM) may never be executed.
An indicator that you haven't properly chained the promises is when you see the function completion log message ("Function execution took...") before other messages you are logging. When you see this, you need to look at the code you are running and confirm whether you have any "floating promises" or are using callback-based APIs. Once you have changed the callback-based APIs to use promises and then made sure they are all chained together properly, you should see a significant boost in performance.
The fixes
Sending the message data to FCM
In your tokenManger file, getAccessToken() could be reworked slightly and sendFcmMessage should be converted to return a Promise:
exports.getAccessToken = () => {
return new Promise(function (resolve, reject) {
const key = require("./service-account.json");
const jwtClient = new google.auth.JWT(
key.client_email,
null,
key.private_key,
SCOPES,
null
);
jwtClient.authorize(
(err, tokens) => err ? reject(err) : resolve(tokens.access_token)
);
});
};
//send message
exports.sendFcmMessage = (fcmMessage) => {
// CHANGED: return the Promise
return this.getAccessToken().then(function (accessToken) {
const options = {
hostname: HOST,
path: PATH,
method: "POST",
headers: {
Authorization: "Bearer " + accessToken,
},
// … plus the body of your notification or data message
};
// CHANGED: convert to Promise:
return new Promise((resolve, reject) => {
const request = https.request(options, (resp) => {
resp.setEncoding("utf8");
resp.on("data", resolve);
resp.on("error", reject);
});
request.on("error", reject);
request.write(JSON.stringify(fcmMessage));
request.end();
});
});
};
However, the above code was built for googleapis ^52.1.0 and google-auth-library ^6.0.3. The modern versions of these modules are v92.0.0 and v7.11.0 respectively. This means you should really update the code to use these later versions like so:
// Import JWT module directly
const { JWT } = require('google-auth-library');
// FIREBASE_CONFIG is a JSON string available in Cloud Functions
const PROJECT_ID = JSON.parse(process.env.FIREBASE_CONFIG).projectId;
const FCM_ENDPOINT = `https://fcm.googleapis.com/v1/projects/${PROJECT_ID}/messages:send`;
const FCM_SCOPES = ["https://www.googleapis.com/auth/firebase.messaging"];
exports.sendFcmMessage = (fcmMessage) => {
const key = require("./service-account.json"); // consider moving outside of function (so it throws an error during deployment if its missing)
const client = new JWT({
email: key.client_email,
key: key.private_key,
scopes: FCM_SCOPES
});
return client.request({ // <-- this uses `gaxios`, Google's fork of `axios` built for Promise-based APIs
url: FCM_ENDPOINT,
method: "POST",
data: fcmMessage
});
}
Better yet, just use the messaging APIs provided by the Firebase Admin SDKs that handle the details for you. Just feed it the message and tokens as needed.
import { initializeApp } from "firebase-admin/app";
import { getMessaging } from "firebase-admin/messaging";
initializeApp(); // initializes using default credentials provided by Cloud Functions
const fcm = getMessaging();
fcm.send(message) // send to one (uses the given token)
fcm.sendAll(messagesArr) // send to many at once (each message uses the given token)
fcm.sendMulticast(message) // send to many at once (uses a `tokens` array instead of `token`)
The Cloud Function
Updating the main Cloud Function, you'd get:
exports.sendChatMessage = functions.firestore
.document("chats/{mealID}/messages/{messageID}")
.onCreate((snap, context) => {
const mealID = context.params.mealID;
const { senderID, senderName, content: messageContent } = snap.data();
const docRef = db.collection("chats").doc(mealID);
/* --> */ return docRef
.get()
.then((doc) => {
if (!doc.exists) { // CHANGED: Fail fast and avoid else statements
console.log(`Could not find "chat:${mealID}"!`);
return false;
}
const { userStatus, to: users, name: mealName, from: fromUser } = doc.data();
const eligibleUsers = users.filter(
(user) => userStatus[user] == "accepted"
);
eligibleUsers.push(fromUser);
// get fcmTokens from eligibleUsers and send the message
/* --> */ return db.collection("users")
.where("uid", "in", eligibleUsers) // WARNING: This will only work for up to 10 users! You'll need to break it up into chunks of 10 if there are more.
.get()
.then(async (snapshot) => {
const fcmTokens = [];
let thumbnailPicURL = "";
// get thumbnailpic of the sender and collect fcmTokens
snapshot.forEach((doc) => {
if (doc.get("uid") == senderID) {
thumbnailPicURL = doc.get("thumbnailPicURL"); // update with given thumbnail pic
} else {
fcmTokens.push(doc.get("fcmToken"));
}
});
const baseMessage = {
notification: {
title: mealName,
body: senderName + ": " + messageContent,
image: thumbnailPicURL || "https://i.imgur.com/8wSudUk.png", // CHANGED: specified fallback image here
},
apns: {
payload: {
aps: {
category: "MESSAGE_RECEIVED",
},
MEAL_ID: mealID,
},
}
}
// log error if fcmTokens empty?
// ----- OPTION 1 -----
// send the message to each fcmToken
const messagePromises = fcmTokens.map((token) => {
if (!token) // handle "" and undefined
return; // skip
/* --> */ return tokenManger
.sendFcmMessage({
message: { ...baseMessage, token }
})
.catch((err) => { // catch the error here, so as many notifications are sent out as possible
console.error(`Failed to send message to "fcm:${token}"`, err);
})
});
await Promise.all(messagePromises); // wait for all messages to be sent out
// --------------------
// ----- OPTION 2 -----
// send the message to each fcmToken
await getMessaging().sendAll(
fcmTokens.map((token) => ({ ...baseMessage, token }))
);
// --------------------
return true;
})
.catch((error) => {
console.log("Error sending messages:", error);
return false;
});
})
.catch((error) => {
console.log("Error getting document:", error);
return false;
});
});
I found out that the culprit is my queries to db. Like #samthecodingman commented, I was creating floating Promises.
Originally, I have codes like:
db.collection("users")
.where("uid", "in", eligibleUsers)
.get()
.then((snapshot) => {...}
All I needed to do is to return that call:
return db.collection("users")
.where("uid", "in", eligibleUsers)
.get()
.then((snapshot) => {...}
Although it's still not instant delivery, it's much faster now.
I am trying to stub a transaction over real time database table.The transaction is inside a function called by a trigger (non HTTP). I can fire the trigger, but I'm not able to stub transaction like this:
var codeRef = admin.database().ref('last_code')
return codeRef.transaction(function (currentCode) {
return currentCode + 1
})
.then(result => {
const {error, committed, snapshot} = result
return snapshot.val()
})
I am using stub Sinon with mocha Unit testing of Cloud Functions. This is the way I tried:
const test = require('firebase-functions-test')();
adminInitStub = sinon.stub(admin, 'initializeApp');
// Now we can require index.js and save the exports inside a namespace called myFunctions.
myFunctions = require('../index');
const refParam = 'last_code';
const databaseStub = sinon.stub();
const refStub = sinon.stub();
const transactionStub = sinon.stub();
Object.defineProperty(admin, 'database', { get: () => databaseStub });
databaseStub.returns({ ref: refStub });
refStub.withArgs(refParam).returns({transaction: function(code) => ({committed: true, snapshot: 999});
But stub transaction fails. I am sure that last line is incorrect, but don't see the solution.
Finally I resolve in this way:
const obj = {
a: (() => function(code){
return 999
})};
let dbSnap = {
val: function() {
return 999;
}
};
var resolveStub = sinon.stub(obj,"a");
const result = {"error": null, "committed" : true, "snapshot" : dbSnap};
resolveStub.resolves(result);
refStub.withArgs("last_booking_code").returns({transaction: resolveStub});
I would like to call an asynchronous function outside the lambda handler with by the following code:
var client;
(async () => {
var result = await initSecrets("MyWebApi");
var secret = JSON.parse(result.Payload);
client= new MyWebApiClient(secret.API_KEY, secret.API_SECRET);
});
async function initSecrets(secretName) {
var input = {
"secretName" : secretName
};
var result = await lambda.invoke({
FunctionName: 'getSecrets',
InvocationType: "RequestResponse",
Payload: JSON.stringify(input)
}).promise();
return result;
}
exports.handler = async function (event, context) {
var myReq = await client('Request');
console.log(myReq);
};
The 'client' does not get initialized. The same code works perfectly if executed within the handler.
initSecrets contains a lambda invocation of getSecrets() which calls the AWS SecretsManager
Has anyone an idea how asynchronous functions can be properly called for initialization purpose outside the handler?
Thank you very much for your support.
I ran into a similar issue trying to get next-js to work with aws-serverless-express.
I fixed it by doing the below (using typescript so just ignore the :any type bits)
const appModule = require('./App');
let server: any = undefined;
appModule.then((expressApp: any) => {
server = createServer(expressApp, null, binaryMimeTypes);
});
function waitForServer(event: any, context: any){
setImmediate(() => {
if(!server){
waitForServer(event, context);
}else{
proxy(server, event, context);
}
});
}
exports.handler = (event: any, context: any) => {
if(server){
proxy(server, event, context);
}else{
waitForServer(event, context);
}
}
So for your code maybe something like
var client = undefined;
initSecrets("MyWebApi").then(result => {
var secret = JSON.parse(result.Payload);
client= new MyWebApiClient(secret.API_KEY, secret.API_SECRET)
})
function waitForClient(){
setImmediate(() => {
if(!client ){
waitForClient();
}else{
client('Request')
}
});
}
exports.handler = async function (event, context) {
if(client){
client('Request')
}else{
waitForClient(event, context);
}
};
client is being called before it has initialised; the client var is being "exported" (and called) before the async function would have completed. When you are calling await client() the client would still be undefined.
edit, try something like this
var client = async which => {
var result = await initSecrets("MyWebApi");
var secret = JSON.parse(result.Payload);
let api = new MyWebApiClient(secret.API_KEY, secret.API_SECRET);
return api(which) // assuming api class is returning a promise
}
async function initSecrets(secretName) {
var input = {
"secretName" : secretName
};
var result = await lambda.invoke({
FunctionName: 'getSecrets',
InvocationType: "RequestResponse",
Payload: JSON.stringify(input)
}).promise();
return result;
}
exports.handler = async function (event, context) {
var myReq = await client('Request');
console.log(myReq);
};
This can be also be solved with async/await give Node v8+
You can load your configuration in a module like so...
const fetch = require('node-fetch');
module.exports = async () => {
const config = await fetch('https://cdn.jsdelivr.net/gh/GEOLYTIX/public/z2.json');
return await config.json();
}
Then declare a _config outside the handler by require / executing the config module. Your handler must be an async function. _config will be a promise at first which you must await to resolve into the configuration object.
const _config = require('./config')();
module.exports = async (req, res) => {
const config = await _config;
res.send(config);
}
Ideally you want your initialization code to run during the initialization phase and not the invocation phase of the lambda to minimize cold start times. Synchronous code at module level runs at initialization time and AWS recently added top level await support in node14 and newer lambdas: https://aws.amazon.com/blogs/compute/using-node-js-es-modules-and-top-level-await-in-aws-lambda/ . Using this you can make the init phase wait for your async initialization code by using top level await like so:
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))
console.log("start init");
await sleep(1000);
console.log("end init");
export const handler = async (event) => {
return {
statusCode: 200,
body: JSON.stringify('Hello from Lambda!'),
};
};
This works great if you are using ES modules. If for some reason you are stuck using commonjs (e.g. because your tooling like jest or ts-node doesn't yet fully support ES modules) then you can make your commonjs module look like an es module by making it export a Promise that waits on your initialization rather than exporting an object. Like so:
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))
const main = async () => {
console.log("start init");
await sleep(1000);
console.log("end init");
const handler = async (event) => {
return {
statusCode: 200,
body: JSON.stringify('Hello from Lambda!'),
};
};
return { handler };
};
# note we aren't exporting main here, but rather the result
# of calling main() which is a promise resolving to {handler}:
module.exports = main();
I have been asked to create a firebase (fb) function that triggers onUpdate. Then I have to gather a bunch of information from the fb database and publish a message so that another function triggers at that point.
fb update triggers functionA
functionA publishes a message
functionB is a subscriber to that topic and is triggered after the message publishes.
I have the basics of the onUpdate trigger below:
const functions = require("firebase-functions"),
Promise = require("promise"),
PubSub = require(`#google-cloud/pubsub`),
admin = require("firebase-admin");
const pubsub = new PubSub();
exports.checkInOrder = functions.database
.ref("/orders/{id}")
.onUpdate((change, context) => {
const after = change.after.val();
// check the status: "pending-pickup" or "fulfilled" TODO
if (after.status === "new") {
console.log("ended because package is new.");
return null;
}
let dsObj = {};
const orderId = context.params.id;
const topicName = 'check-in-order';
const subscriptionName = 'check-in-order';
return // how would I send the message to the pubsub here?
});
So to summarize:
How do I send a message to pubsub
How do I subscribe a firebase function to trigger when a topic receives a message?
If it sounds very confusing I'm sorry - I am completely lost here. Thanks!
So I finally figured it out. Pretty straight forward, just felt overwhelmed with learning all of this stuff at once and in a rushed time frame. Below is my code. I included the whole page so in case this might help someone else out there in the future.
const functions = require("firebase-functions"),
Promise = require("promise"),
PubSub = require(`#google-cloud/pubsub`),
admin = require("firebase-admin");
const init = () => {
const topicName = "check-in-order";
pubsub
.createTopic(topicName)
.then(results => {
const topic = results[0];
console.log(`Topic ${topicName} created.`);
return;
})
.catch(err => {
console.error("ERROR on init:", err);
return;
});
};
const pubsub = new PubSub();
exports.orderCreated = functions.database
.ref("/orders/{id}")
.onUpdate((change, context) => {
console.log("it's happening!");
const after = change.after.val();
console.log("after::::>", after)
if (after.status === "new") {
console.log('stopped because status is new');
return null;
}
if (after.status === "pending-pickup" || after.status === "fulfilled") {
const orderId = context.params.id;
const topicName = "check-in-order";
let { assignedSlot, userId, parcelLockerId, carrier, trackingNumber, orderInDate, pickUpCode, status, } = after;
const dsObj = {
order: {
orderId,
userId,
parcelLockerId,
carrier,
trackingNumber,
orderInDate,
pickUpCode,
status,
}
};
const dataBuffer = new Buffer.from(dsObj.toString());
// publish to trigger check in function
return pubsub
.topic(topicName)
.publisher()
.publish(dataBuffer)
.then(messageId => {
console.log(`:::::::: Message ${messageId} has now published. :::::::::::`);
return true;
})
.catch(err => {
console.error("ERROR:", err);
throw err;
});
}
return false;
});
exports.checkInOrder = () => {
}
exports.checkIn = functions.pubsub.topic('check-in-order').onPublish((message) => {
console.log("everything is running now", message);
return true;
});
init();
I am converting the use of Firebase Storage to use the Angularfire2 library (currently v5.0.0-rc.5-next) which means I am now using observables rather than promises.
How can I catch error such as storage/object-not-found and react accordingly?
This is currently my code but I cannot add a catch to it as some examples I found.
const avatarRef = this.afStorage.ref('${userId}/avatar/${this.avatarThumbnail}${user.avatar}');
avatarRef.getDownloadURL()
.take(1)
.subscribe((avatarUrl) => {
resolve(avatarUrl);
});
At its most basic, observers take an error callback to receive any unhandled errors in an observable stream. getDownloadURL() returns Observable that is why you need to subscribe. If you get an error (file not found or other) you will invoke code from error callback only.
avatarRef.getDownloadURL()
.take(1)
.subscribe((avatarUrl) => {
// Do something with avatarUrl here
console.log(avatarUrl);
}, (error) => {
// Handle error here
// Show popup with errors or just console.error
console.error(error);
});
Also I suggest you to read articles about error handling using RxJS and difference between Observable and Promise: link1, link2
The following solution work for me
startUpload(file) {
// The storage path
const path = `image${new Date().getTime()}.jpg`;
// Reference to storage bucket
const ref = this.storage.ref(path);
let image = 'data:image/jpeg;base64,' + file;
// The main task
return new Promise((resolve, reject) => {
const upload = ref.putString(image, 'data_url');
const sub = upload.snapshotChanges().pipe(
finalize(async () => {
try {
const photoURL = await ref.getDownloadURL().toPromise();
this.message.senderUid = this.currentUser.uid;
this.message.receiverUid = this.selectedUser.uid;
this.message.text = this.inputText && this.inputText !== '' ? this.inputText : 'File';
this.message.senderName = this.currentUser.name;
this.message.chatId = this.chatId;
this.message.file = photoURL;
this.firebaseService.insertMessage(this.message)
.then(() => {
this.inputText = '';
this.message.file = null;
this.scrollToBottomOnInit();
});
resolve({photoURL})
} catch (err) {
this.inputText = '';
this.message.file = null;
reject(err)
}
sub.unsubscribe()
})
).subscribe((data) => {
console.log('storage: ', data)
})
})
}
Source: https://github.com/angular/angularfire/issues/1736#issuecomment-515798352