I am trying to update several Firestore documents, based on the result of a third-party service inside a transaction. Problem is, I am getting the following error:
Error: Cannot modify a WriteBatch that has been committed.
Here is my code:
export default async function debitDueTransactions(context: any) {
const now = new Date().getTime();
return db.runTransaction(async (transaction: FirebaseFirestore.Transaction) => {
const chargesToCaptureRef = db.collection(`charges_to_capture`)
.where('dateToCapture', '>=', now)
.where('dateToCapture', '<=', (now + 86400000))
.where('captureResult', '==', null);
return transaction.get(chargesToCaptureRef).then((chargeToCaptureQuerySnap: FirebaseFirestore.QuerySnapshot) => {
chargeToCaptureQuerySnap.forEach(async (doc: FirebaseFirestore.QueryDocumentSnapshot) => {
const chargeToCapture = <ChargeToCapture>doc.data();
chargeToCapture.id = doc.id;
let errorKey = null;
// Calling third party service here, waiting response
const captureResult = await captureCharge(chargeToCapture.chargeId).catch((error: any) => {
errorKey = error.code ? error.code : 'unknown_error';
});
transaction.update(doc.ref, { captureResult: captureResult, errorKey: errorKey });
});
return new Promise((resolve) => { resolve(); });
})
});
}
Can't get what I am doing wrong, any idea ?
As you can see from the API documentation, transaction.get() only accepts a DocumentReference type object. You're passing it a Query object. A Firestore transaction isn't capable of transacting on a Query. If you want to transact on all the documents returned from a Query, you should perform the query before the transaction, then use transaction.get() on each DocumentReference individually.
Related
I have create document like this in react native, I am using rnfirebase library
firestore()
.collection('WaterCanData')
.doc(EntryDate)
.collection('Entries')
.doc(values.customerName)
.set({
CustomerName: values.customerName,
CansOut: values.cansOut,
JarsOut: values.jarsOut,
EmptyCansIn: values.emptyCansIn,
JarsIn: values.jarsIn,
Bottles: values.bottles,
Ice: values.ice
})
.then(() => {
console.log('Entry added!!!!!!!!!');
})
When I try to retrieve EntryDate from WaterCanData Coellection I am not able to fetch it(Document name appears in italic font), So how should I retrive this document which contains a subcollection, Below I have attached my ss of data structure
Data structure
Data structuree
The reason your document appears in italics is because it doesn't currently exist. In Cloud Firestore, subcollections can exist without requiring their parent document to also exist.
Non-existant documents will not appear in queries or snapshots in the client SDKs as stated in the Firebase Console.
This document does not exist, it will not appear in queries or snapshots
If you want to be able to get your entry dates, you need to create the document (which can be empty).
firebase.firestore()
.collection('WaterCanData')
.doc(EntryDate)
.set({}); // an empty document
To create the document at the same time as an entry on it's subcollection, you can use a batched write like so:
const db = firebase.firestore();
const batch = db.batch();
// get references to the relevant locations
const entryDateRef = db
.collection('WaterCanData')
.doc(EntryDate);
const customerRef = entryDateRef
.collection('Entries')
.doc(values.customerName);
// queue the data to write
batch.set(entryDateRef, {});
batch.set(customerRef, {
CustomerName: values.customerName,
CansOut: values.cansOut,
JarsOut: values.jarsOut,
EmptyCansIn: values.emptyCansIn,
JarsIn: values.jarsIn,
Bottles: values.bottles,
Ice: values.ice
})
// make changes to database
batch.commit()
.then(() => {
console.log('Entry added!!!!!!!!!');
});
This will then allow you to list all of the entry dates in your database using something like:
firebase.firestore().collection('WaterCanData')
.get()
.then((querySnapshot) => {
querySnapshot.forEach(doc => {
const entryDate = doc.id;
// const customerEntriesRef = doc.ref.collection('Entries');
console.log('Entry date found: ' + entryDate);
}
});
If (as an example) you wanted to also find how many entries were linked to a given date, you would need to also query each subcollection (here the code gets a little more confusing).
firebase.firestore().collection('WaterCanData')
.get()
.then((querySnapshot) => {
const fetchSizePromises = [];
// for each entry date, get the size of it's "Entries" subcollection
querySnapshot.forEach(doc => {
const entryDate = doc.id;
const customerEntriesRef = doc.ref.collection('Entries');
// if this get() fails, just store the error rather than throw it.
const thisEntrySizePromise = customerEntriesRef.get()
.then(
(entriesQuerySnapshot) => {
return { date: entryDate, size: entriesQuerySnapshot.size }
},
(error) => {
return { date: entryDate, size: -1, error }
}
);
// add this promise to the queue
fetchSizePromises.push(thisEntrySizePromise)
}
// wait for all fetch operations and return their results
return Promise.all(fetchSizePromises);
})
.then((entryInfoResults) => {
// for each entry, log the result
entryInfoResults.forEach((entryInfo) => {
if (entryInfo.error) {
// this entry failed
console.log(`${entryInfo.date} has an unknown number of customers in its Entries subcollection due to an error`, entryInfo.error);
} else {
// got size successfully
console.log(`${entryInfo.date} has ${entryInfo.size} customers in its Entries subcollection`);
}
}
});
Using below code you can console every document id inside waterCanData collection. In your database you have only one document, then it will console your document id. (10042021)
firestore()
.collection('WaterCanData')
.get()
.then((querySnapshot) => {
querySnapshot.forEach((doc) => {
console.log(doc.id)
});
})
So, I don't really know how to write JS, I am developing a mobile app in Flutter, and I would be grateful for some help and clarifications regarding Future/Promises in JS.
I got a collection of posts for each user, and I want to create an .onCreate function which when a user posts a new post (a new document is created inside the 'posts/userId/user_posts' collection), then it gets all the user's followers (from a collection 'user_followers/userUid') and for each follower, it writes the postUid and postOwnerUid to that follower's newsFeed collection ('user_news_feed/followerId').
This is what I got right now, but I am walking blind, since I really don't know JS and I don't know how can I await a write function while inside a get function.
And how do I prevent Cloud Timeouts? If for instance the user has 1000 followers, how can I prevent Firebase from shutting down my function and making sure all the followers are notified?
exports.writeToUserNewsFeed = functions.firestore
.document('posts/{userId}/user_posts/{postId}')
.onCreate((snap, context) => {
const postData = snap.data();
const postUid = postData['post_uid'];
const userUid = postData['user_uid'];
const postCreationDate = postData['post_creation_date'];
var docRef = db.collection('user_followers').doc(userUid).collection('followers');
docRef.get().then((querySnapshot) => {
querySnapshot.forEach((doc) => {
db.collection('user_news_feed')
.doc(doc.data['uid'])
.collection('feed')
.document(postUid)
.set({
'post_uid': postUid,
'user_uid': userUid,
'post_uid': postCreationDate,
});
});
});
});
As explained in the doc, in a background Cloud Function like an onCreate() for Firestore, you need to return a Promise when all the asynchronous work is completed. So in your case, one possibility is to use Promise.all() because you don't know upfront how many documents are in the followers subcollection. Since Promise.all() returns a single Promise you can include it in the Promise chain that you need to return in the Cloud Function.
exports.writeToUserNewsFeed = functions.firestore
.document('posts/{userId}/user_posts/{postId}')
.onCreate((snap, context) => {
const postData = snap.data();
const postUid = postData['post_uid'];
const userUid = postData['user_uid'];
const postCreationDate = postData['post_creation_date'];
var followersColRef = db.collection('user_followers').doc(userUid).collection('followers');
return followersColRef.get().then((querySnapshot) => { // <= See return here
const promises = [];
querySnapshot.forEach((doc) => {
promises.push(
db.collection('user_news_feed')
.doc(doc.data['uid'])
.collection('feed')
.doc(postUid)
.set({
'post_uid': postUid,
'user_uid': userUid,
'post_uid': postCreationDate,
})
);
});
return Promise.all(promises); // <= See return here
})
.catch(error => {
console.log(error);
return null;
})
});
Note that instead of using Promise.all() you could also use a batched write but there is a limit of 500 operations for a batched write.
Assume there is a collection of users and each user is associated with accounts, which are kept in a separate collection. For each account there is a balance which is updated periodically by some external means (e.g. the http trigger below). I need to be able to query for the user's total balance across all of her accounts.
I added onUpdate trigger which gets called everytime an account changes and updates the total accordingly. However, it seems that there is some race condition e.g. when two accounts get updated around the same time: after onUpdate is called for the first account and updates the total balance, it is still not updated when onUpdate is called for the second account. I'm guessing I need to somehow use "transaction" for the bookkeeping but not sure how.
const data = {
'users/XXX': {
email: "a#b.com",
balance: 0
},
"accounts/YYY": {
title: "Acc1",
userID: "XXX"
balance: 0
},
"accounts/ZZZ": {
title: "Acc2",
userID: "XXX"
balance: 0
}
};
exports.updateAccounts = functions.https.onRequest((request, response) => {
admin.firestore().collection('accounts').get().then((accounts) => {
accounts.forEach((account) => {
return admin.firestore().collection('accounts').doc(account.id).update({balance:
WHATEVER});
})
response.send("Done");
});
exports.updateAccount = functions.firestore
.document('accounts/{accountID}')
.onUpdate((change, context) => {
const userID = change.after.data().userID;
admin.firestore().doc("users/"+userID).get().then((user) => {
const new_balance = change.after.data().balance;
const old_balance = change.before.data().balance;
var user_balance = user.data().balance + new_balance - old_balance;
admin.firestore().doc("users/"+userID).update({balance: user_balance});
});
});
By looking at your code we can see several parts of it that could lead to incorrect results. It is not possible, without thoroughly testing and reproducing your problem, to be sure at 100% that correcting them will totally solve your problem but it is most probably the cause of the problems.
HTTP Cloud Function:
With the forEach() loop you are calling several asynchronous operations (the update() method) but you don't wait that all these asynchronous operations are completed before sending back the response. You should do as follows, using Promise.all() to wait all the asynchronous methods are completed before sending the response:
exports.updateAccounts = functions.https.onRequest((request, response) => {
const promises = [];
admin.firestore().collection('accounts').get()
.then(accounts => {
accounts.forEach((account) => {
promises.push(admin.firestore().collection('accounts').doc(account.id).update({balance: WHATEVER}));
return Promise.all(promises);
})
.then(() => {
response.send("Done");
})
.catch(error => {....});
});
onUpdate background triggered Cloud Function
There you need to correctly return the Promises chain in order to indicate to the platform when the Cloud Function is complete. The following should do the trick:
exports.updateAccount = functions.firestore
.document('accounts/{accountID}')
.onUpdate((change, context) => {
const userID = change.after.data().userID;
return admin.firestore().doc("users/"+userID).get() //Note the return here. (Note that in the HTTP Cloud Function we don't need it! see the link to the video series below)
.then(user => {
const new_balance = change.after.data().balance;
const old_balance = change.before.data().balance;
var user_balance = user.data().balance + new_balance - old_balance;
return admin.firestore().doc("users/"+userID).update({balance: user_balance}); //Note the return here.
});
});
I would suggest that you watch the 3 videos about "JavaScript Promises" from the Firebase video series: https://firebase.google.com/docs/functions/video-series/. They explain all the key points that were corrected above.
At first sight, it seems that if you modify, in the updateAccounts Cloud Function, several account documents that share the same user you will indeed need to implement the user balance update in a transaction, as several instances of the updateAccount Cloud Function may be triggered in parallel. The doc on Transactions is here.
Update:
You could implement a Transaction as follows in the updateAccounts Cloud Function (untested):
exports.updateAccount = functions.firestore
.document('accounts/{accountID}')
.onUpdate((change, context) => {
const userID = change.after.data().userID;
const userRef = admin.firestore().doc("users/" + userID);
return admin.firestore().runTransaction(transaction => {
// This code may get re-run multiple times if there are conflicts.
return transaction.get(userRef).then(userDoc => {
if (!userDoc.exists) {
throw "Document does not exist!";
}
const new_balance = change.after.data().balance;
const old_balance = change.before.data().balance;
var user_balance = userDoc.data().balance + new_balance - old_balance;
transaction.update(userRef, {balance: user_balance});
});
}).catch(error => {
console.log("Transaction failed: ", error);
return null;
});
});
In addition to what #Renaud Tarnec covered in their answer, you may also want to consider the following approaches:
Batched Write
In your updateAccounts function, you are writing many pieces of data at once, if any one of these fail, you may end up with a database that contains a mix of correctly updated data and data that had failed to be updated.
To solve this, you can use a batched write to write the data atomically where all new data is updated successfully or none of your data is written leaving your database in a known state.
exports.updateAccounts = functions.https.onRequest((request, response) => {
const db = admin.firestore();
db.collection('accounts')
.get()
.then((qsAccounts) => { // qs -> QuerySnapshot
const batch = db.batch();
qsAccounts.forEach((accountSnap) => {
batch.update(accountSnap.ref, {balance: WHATEVER});
})
return batch.commit();
})
.then(() => response.send("Done"))
.catch((err) => {
console.log("Error whilst updating balances via HTTP Request:", err);
response.status(500).send("Error: " + err.message)
});
});
Splitting the counters
Instead of storing a single "balance" in your document, it may instead be desirable (based on what you are trying to do) to store each account's balance in the user's document.
"users/someUser": {
...,
"balances": {
"accountId1": 10,
"accountId4": -20,
"accountId23": 5
}
}
If you need the cumulative balance, just add them together on the client. If you need to remove a balance, simply delete it's entry in the user document.
exports.updateAccount = functions.firestore
.document('accounts/{accountID}')
.onUpdate((change, context) => {
const db = admin.firestore();
const accountID = context.params.accountID;
const newData = change.after.data();
const accountBalance = newData.balance;
const userID = newData.userID;
return db.doc("users/"+userID)
.get()
.then((userSnap) => {
return db.doc("users/"+userID).update({["balances." + accountID]: accountBalance});
})
.then(() => console.log(`Successfully updated account #${accountID} balance for user #${userID}`))
.catch((err) => {
console.log(`Error whilst updating account #${accountID} balance for user #${userID}`, err);
throw err;
});
});
Trying to read a pushToken from a given user in the users collection (after an update operation on another collection) returns undefined
exports.addDenuncia = functions.firestore
.document('Denuncias/{denunciaID}')
.onWrite((snap, context) => {
const doc = snap.after.data()
const classificadoId = doc.cid
const idTo = doc.peerId
db.collection('Classificados').doc(classificadoId)
.update({
aprovado: false
})
.then(r => {
getToken(idTo).then(token => {
// sendMsg...
})
}).catch(updateErr => {
console.log("updateErr: " + updateErr)
})
async function getToken(id) {
let response = "getTokenResponse"
console.log("id in getToken: " + id)
return db.collection('users').doc(id).get()
.then(user => {
console.log("user in getToken: " + user.data())
response = user.data().pushToken
})
.catch(e => {
console.log("error get userToken: " + e)
response = e
});
return response
}
return null
});
And this is from the FB console log:
-1:43:33.906 AM Function execution started
-1:43:36.799 AM Function execution took 2894 ms, finished with status: 'ok'
-1:43:43.797 AM id in getToken: Fm1RwJaVfmZoSgNEFHq4sbBgoEh1
-1:43:49.196 AM user in getToken: undefined
-1:43:49.196 AM error get userToken: TypeError: Cannot read property 'pushToken' of undefined
-1:43:49.196 AM returned token: undefined
And we can see in this screenshot from the db that the doc does exist:
Hope someone can point me to what I'm doing wrong here.
added screenshot of second example of #Renaud as deployed:
As Doug wrote in his comment, you need to "return a promise from the top level function that resolves when all the async work is complete". He also explains that very well in the official video series: https://firebase.google.com/docs/functions/video-series/ (in particular the 3 videos titled "Learn JavaScript Promises"). You should definitely watch them, highly recommended!
So, the following modifications to your code should work (untested):
exports.addDenuncia = functions.firestore
.document('Denuncias/{denunciaID}')
.onWrite(async (snap, context) => { // <- note the async keyword
try {
const doc = snap.after.data()
const classificadoId = doc.cid
const idTo = doc.peerId
await db.collection('Classificados').doc(classificadoId)
.update({
aprovado: false
});
const userToSnapshot = await db.collection('users').doc(idTo).get();
const token = userToSnapshot.data().pushToken;
await sendMsg(token); // <- Here you should take extra care to correctly deal with the asynchronous character of the sendMsg operation
return null; // <-- This return is key, in order to indicate to the Cloud Function platform that all the asynchronous work is done
} catch (error) {
console.log(error);
return null;
}
});
Since you use an async function in your code, I've used the async/await syntax but we could very well write it by chaining the promises with the then() method, as shown below.
Also, I am not sure, in your case, that it adds any value to put the code that gets the token in a function (unless you want to call it from other Cloud Functions but then you should move it out of the addDenuncia Cloud Function). That's why it has been replaced by two lines of code within the main try block.
Version with chaining promises via the then() method
In this version we chain the different promises returned by the asynchronous methods with the then() method. Compared to the async/await version above, it shows very clearly what means "to return a promise from the top level function that resolves when all the asynchronous work is complete".
exports.addDenuncia = functions.firestore
.document('Denuncias/{denunciaID}')
.onWrite((snap, context) => { // <- no more async keyword
const doc = snap.after.data()
const classificadoId = doc.cid
const idTo = doc.peerId
return db.collection('Classificados').doc(classificadoId) // <- we return a promise from the top level function
.update({
aprovado: false
})
.then(() => {
return db.collection('users').doc(idTo).get();
})
.then(userToSnapshot => {
if {!userToSnapshot.exists) {
throw new Error('No document for the idTo user');
}
const token = userToSnapshot.data().pushToken;
return sendMsg(token); // Again, here we make the assumption that sendMsg is an asynchronous function
})
.catch(error => {
console.log(error);
return null;
})
});
I got a querysnapshot in a function.
And want to bring the whole querysnapshot to another function (functionTwo).
In functionTwo, I want to get a specific document in the querysnapshot WITHOUT forEach. The specific doc can be changed by different cases.
ref_serial_setting.get()
.then(querysnapshot => {
return functionTwo(querysnapshot)
})
.catch(err => {
console.log('Error getting documents', err)
})
let functionTwo = (querysnapshot) => {
// getting value
const dataKey_1 = "dataKey_1"
// Tried 1
const value = querysnapshot.doc(dataKey_1).data()
// Tried 2
const value = querysnapshot.document(dataKey_1).data()
// Tried 3 (Put 'data_name': dataKey_1 in that doc)
const value = querysnapshot.where('data_name', '==', dataKey_1).data()
}
The result are all these trying are not a function.
How can I get specific document data from querysnapshot??
or
Is there any easy method to change the querysnapshot to JSON?
You can get an array of the document snapshots by using the docs property of a QuerySnapshot. After that you'll have to loop through getting the data of the doc snapshots looking for your doc.
const docSnapshots = querysnapshot.docs;
for (var i in docSnapshots) {
const doc = docSnapshots[i].data();
// Check for your document data here and break when you find it
}
Or if you don't actually need the full QuerySnapshot, you can apply the filter using the where function before calling get on the query object:
const dataKey_1 = "dataKey_1";
const initialQuery = ref_serial_setting;
const filteredQuery = initialQuery.where('data_name', '==', dataKey_1);
filteredQuery.get()
.then(querySnapshot => {
// If your data is unique in that document collection, you should
// get a query snapshot containing only 1 document snapshot here
})
.catch(error => {
// Catch errors
});
Theres an easy way to do this, each QuerySnapshot has a property docs which returns an array of QueryDocumentSnapshots. See QuerySnapshot documentation.
let citiesRef = db.collection('cities');
let query = citiesRef.where('capital', '==', true).get().then(snapshot => {
snapshot.docs[0]; // => returns first document
});
let citiesRef = db.collection('cities');
let query = citiesRef.where('capital', '==', true).get()
.then(snapshot => {
if (snapshot.empty) {
console.log('No matching documents.');
return;
}
snapshot.forEach(doc => {
console.log(doc.id, '=>', doc.data());
});
})
.catch(err => {
console.log('Error getting documents', err);
});
from https://firebase.google.com/docs/firestore/query-data/get-data
you can use this code :
const querySnapshot = await getDocs(collection(db, "collectionNaame"));
const docSnapshots = querySnapshot.docs;
for (var i in docSnapshots) {
console.log(i)
const doc = docSnapshots[i].data();
console.log(doc)
Just do
db.doc(<<ref>>).get()
this returns a promise
[here ]: https://firebase.google.com/docs/firestore/query-data/get-data#get_a_document is the link to the docs