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How to delete all items from a DynamoDB table?

I want to delete all items (aka records/rows) in a DynamoDB table. I understand that the documentation advises to simply drop the whole table and re-create it, but I've created my table with AWS Amplify and I don't want to risk breaking the rest of my stack.
I've had a look at the DynamoDB API and the aws-sdk (I'm using javascript). I can delete single items in the database but I'm struggling to expand that to deleting multiple items.
// Delete single item:
import { DeleteItemCommand } from "#aws-sdk/client-dynamodb";
import { ddbClient } from "./dynamoDbClient";
const tableName = "myTableName";
const itemId = "12f10644-546c-45f4-8309-c208061e9737";
export async function deleteItemDynamoDb() {
const command = new DeleteItemCommand({
TableName: tableName,
Key: {
id: {
S: "12f10644-546c-45f4-8309-c208061e9737",
},
},
});
const response = await ddbClient.send(command);
}

I can't figure out how to use the BatchGetItemCommand to get all/many records from a table, so I have fudged a solution by combining AppSync and DynamoDB:
export async function listCardsIncDeleted(): Promise<Card[]> {
const getCardQueryString = `query listCards {
listCards(limit:500) {
items {
id
name
_deleted
_version
status
}
}
}`;
try {
const response = (await appSyncClient.query({
query: gql(getCardQueryString),
fetchPolicy: "network-only",
})) as {
data: { listCards: { items: Card[]; __typename: "ModelCardConnection" } };
};
const { items } = response.data.listCards;
console.log({ items });
return items;
} catch (error) {
console.log(error);
throw new Error("ERROR");
}
}
async function deleteAllTimes(arrayOfCardObjects: { id: string }[]) {
let count = 0;
for await (const curCard of arrayOfCardObjects) {
await new Promise((resolve) => setTimeout(resolve, 50));
const deleteResponse = await deleteById(curCard.id);
count++;
console.log({ deleteResponse, curCardId: curCard.id, count });
}
return count;
}
async function listAppSyncThenDelete() {
const listOfCards = await listCardsIncDeleted();
const deletedAll = deleteAllTimes(listOfCards);
return deletedAll;
}

typescript node insert on mongodb database

im a total newbie in js (typescript, mongoDB, node.)
i just found that my code is not behaving as i expected, im getting 6 registers on the mongoDB instead of just one, it should check if the register exists and then update it, i dont know if it is something related to the await / async or i am doing something wrong, thanks in advace, here is my code.
fields.forEach((value) => {
try {
const mongoConnection = new DocumentDbRepository();
let checksIfExists = await mongoConnection.getValue(key, information[uniqueValue]);
if(checksIfExists==null){
let insert = await mongoConnection.insertValue(information);
console.log(insert);
}
if(checksIfExists?.passValue===information.passValue){
console.log('---------update---------');
let sons = Object.values(information.ticketToRide);
information.ticketToRide = sons;
let update = await mongoConnection.updateRegister(information, checksIfExists._id);
console.log(update);
} else {
console.log('---------insert---------');
let sons = Object.values(information.ticketToRide);
information = sons;
let insert = await mongoConnection.insertValue(information);
console.log(insert);
}
} catch (error) {
console.log(error)
}
}
async getValue(uniqueValue: any, keyValue:any) {
if (this._connection == null) {
await this.connect();
}
const db = this._connection.db(DocumentDbRepository.DbName);
const ticketToRide = db.collection("ticketToRide");
const query = {};
query[uniqueValue] = ''+keyValue+'';
const passInfo = await ticketToRide.findOne(query);
return passInfo;
}
async insertValue(information: any) {
if (this._connection == null) {
await this.connect();
}
const db = this._connection.db(DocumentDbRepository.DbName);
const ticketToRide = db.collection("ticketToRide");
let check = await ticketToRide.insertOne(
information
)
return check;
}

First, you don't need to create a connection inside the loop.
Second, mongodb has an update() or updateMany() method that has a special option { upsert: true }. If it is passed, insert will happen automatically.
Usage example:
Person.update( { name: 'Ted' }, { name: 'Ted', age : 50 }, { upsert: true })

Get all records from collection with all refrences in Firestore

Hi I'm currently blocked because I can't get all records from a collection with references values.
I would like to get all records from collection events (it works) but when I wanna merge the category information associated with categoryId my code doesn't work anymore.
Events collection
Categories collection
export const getEventsRequest = async () => {
const output = [];
const data = await firebase.firestore().collection('events').get();
data.forEach(async (doc) => {
const {
name,
address,
city,
duration,
level,
startDate,
maxPeople,
categoryId,
} = doc.data();
const { name: categoryName, color } = (
await firebase.firestore().collection('categories').doc(categoryId).get()
).data();
output.push({
name,
address,
city,
duration,
level,
startDate,
maxPeople,
category: { name: categoryName, color },
});
});
return output;
};
Example testing in a React Native project
const [events, setEvents] = useState([]);
const [isEventsLoading, setIsEventsLoading] = useState(false);
const getEvents = async () => {
setEvents([]);
setIsEventsLoading(true);
try {
const evts = await getEventsRequest();
setEvents(evts);
setIsEventsLoading(false);
} catch (e) {
console.error(e);
}
};
useEffect(() => {
getEvents();
}, []);
console.log('events', events);
Output
events Array []
Expected
events Array [
{
name : "blabla",
address: "blabla",
city: "blabla",
duration: 60,
level: "hard",
startDate: "13/04/2021",
maxPeople: 7,
category: {
name: "Football",
color: "#fff"
},
},
// ...
]
I don't know if there is a simpler method to retrieve this kind of data (for example there is populate method on mongo DB).
Thank you in advance for your answers.

When you use CollectionReference#get, it returns a Promise containing a QuerySnapshot object. The forEach method on this class is not Promise/async-compatible which is why your code stops working as you expect.
What you can do, is use QuerySnapshot#docs to get an array of the documents in the collection, then create a Promise-returning function that processes each document and then use it with Promise.all to return the array of processed documents.
In it's simplest form, it would look like this:
async function getDocuments() {
const querySnapshot = await firebase.firestore()
.collection("someCollection")
.get();
const promiseArray = querySnapshot.docs
.map(async (doc) => {
/* do some async work */
return doc.data();
});
return Promise.all(promiseArray);
}
Applying it to your code gives:
export const getEventsRequest = async () => {
const querySnapshot = await firebase.firestore()
.collection('events')
.get();
const dataPromiseArray = querySnapshot.docs
.map(async (doc) => {
const {
name,
address,
city,
duration,
level,
startDate,
maxPeople,
categoryId,
} = doc.data();
const { name: categoryName, color } = (
await firebase.firestore().collection('categories').doc(categoryId).get()
).data();
return {
name,
address,
city,
duration,
level,
startDate,
maxPeople,
category: { name: categoryName, color },
};
});
// wait for each promise to complete, returning the output data array
return Promise.all(dataPromiseArray);
};

How to iterate over objects stored in a JavaScript array

I'm coding a simple JavaScript currency converter. Pulled the currency data from an API and stored it to a state object. Next, I wanted to add currency name, country and symbol to the app so I'm pulling that data from a Rest Countries API and storing it to "currencies" array.
Here's the code:
export const state = {
date: [],
time: {},
currency: [],
rates: {},
result: [],
};
export const getSymbolsCountry = async function (symbol) {
try {
const data = await fetch(`https://restcountries.eu/rest/v2/currency/${symbol}`);
const json = await data.json();
addInfoToSymbol(json[0]);
} catch (err) {
console.log(err);
}
};
function addInfoToSymbol(data) {
let country = {
code: data.currencies[0].code,
symbol: data.currencies[0].symbol,
flag: data.flag,
country: data.name,
};
state.currency.push(country);
}
Console logging the currency from state shows that it's an array but using map or forEach on it does nothing.
console log state.currency
Could someone please help me understand what I'm doing wrong cause I can't wrap my head around it.

What do you mean by using map of forEach on it does nothing ?
Here is an example where I use forEach on state.currency and its working perfectly.
const state = {
currency: []
};
const getSymbolsCountry = async function (symbol) {
try {
const data = await fetch(`https://restcountries.eu/rest/v2/currency/${symbol}`);
const json = await data.json();
addInfoToSymbol(json[0]);
} catch (err) {
console.log(err);
}
};
function addInfoToSymbol(data) {
let country = {
code: data.currencies[0].code,
symbol: data.currencies[0].symbol,
flag: data.flag,
country: data.name,
};
state.currency.push(country);
}
Promise.all([
getSymbolsCountry("EUR"),
getSymbolsCountry("USD"),
getSymbolsCountry("JPY")
])
.then(() =>
state.currency.forEach(({code}) =>
$("#result").append("<li>" + code + "</li>")
)
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<ul id="result"></ul>

How can I update more than 500 docs in Firestore using Batch?

I'm trying to update a field timestamp with the Firestore admin timestamp in a collection with more than 500 docs.
const batch = db.batch();
const serverTimestamp = admin.firestore.FieldValue.serverTimestamp();
db
.collection('My Collection')
.get()
.then((docs) => {
serverTimestamp,
}, {
merge: true,
})
.then(() => res.send('All docs updated'))
.catch(console.error);
This throws an error
{ Error: 3 INVALID_ARGUMENT: cannot write more than 500 entities in a single call
at Object.exports.createStatusError (C:\Users\Growthfile\Desktop\cf-test\functions\node_modules\grpc\src\common.js:87:15)
at Object.onReceiveStatus (C:\Users\Growthfile\Desktop\cf-test\functions\node_modules\grpc\src\client_interceptors.js:1188:28)
at InterceptingListener._callNext (C:\Users\Growthfile\Desktop\cf-test\functions\node_modules\grpc\src\client_interceptors.js:564:42)
at InterceptingListener.onReceiveStatus (C:\Users\Growthfile\Desktop\cf-test\functions\node_modules\grpc\src\client_interceptors.js:614:8)
at callback (C:\Users\Growthfile\Desktop\cf-test\functions\node_modules\grpc\src\client_interceptors.js:841:24)
code: 3,
metadata: Metadata { _internal_repr: {} },
details: 'cannot write more than 500 entities in a single call' }
Is there a way that I can write a recursive method which creates a batch object updating a batch of 500 docs one by one until all the docs are updated.
From the docs I know that delete operation is possible with the recursive approach as mentioned here:
https://firebase.google.com/docs/firestore/manage-data/delete-data#collections
But, for updating, I'm not sure how to end the execution since the docs are not being deleted.

I also ran into the problem to update more than 500 documents inside a Firestore collection. And i would like to share how i solved this problem.
I use cloud functions to update my collection inside Firestore but this should also work on client side code.
The solution counts every operation which is made to the batch and after the limit is reached a new batch is created and pushed to the batchArray.
After all updates are completed the code loops through the batchArray and commits every batch which is inside the array.
It is important to count every operation set(), update(), delete() which is made to the batch because they all count to the 500 operation limit.
const documentSnapshotArray = await firestore.collection('my-collection').get();
const batchArray = [];
batchArray.push(firestore.batch());
let operationCounter = 0;
let batchIndex = 0;
documentSnapshotArray.forEach(documentSnapshot => {
const documentData = documentSnapshot.data();
// update document data here...
batchArray[batchIndex].update(documentSnapshot.ref, documentData);
operationCounter++;
if (operationCounter === 499) {
batchArray.push(firestore.batch());
batchIndex++;
operationCounter = 0;
}
});
batchArray.forEach(async batch => await batch.commit());
return;

I liked this simple solution:
const users = await db.collection('users').get()
const batches = _.chunk(users.docs, 500).map(userDocs => {
const batch = db.batch()
userDocs.forEach(doc => {
batch.set(doc.ref, { field: 'myNewValue' }, { merge: true })
})
return batch.commit()
})
await Promise.all(batches)
Just remember to add import * as _ from "lodash" at the top. Based on this answer.

You can use default BulkWriter. This method used 500/50/5 rule.
Example:
let bulkWriter = firestore.bulkWriter();
bulkWriter.create(documentRef, {foo: 'bar'});
bulkWriter.update(documentRef2, {foo: 'bar'});
bulkWriter.delete(documentRef3);
await close().then(() => {
console.log('Executed all writes');
});

As mentioned above, #Sebastian's answer is good and I upvoted that too. Although faced an issue while updating 25000+ documents in one go.
The tweak to logic is as below.
console.log(`Updating documents...`);
let collectionRef = db.collection('cities');
try {
let batch = db.batch();
const documentSnapshotArray = await collectionRef.get();
const records = documentSnapshotArray.docs;
const index = documentSnapshotArray.size;
console.log(`TOTAL SIZE=====${index}`);
for (let i=0; i < index; i++) {
const docRef = records[i].ref;
// YOUR UPDATES
batch.update(docRef, {isDeleted: false});
if ((i + 1) % 499 === 0) {
await batch.commit();
batch = db.batch();
}
}
// For committing final batch
if (!(index % 499) == 0) {
await batch.commit();
}
console.log('write completed');
} catch (error) {
console.error(`updateWorkers() errored out : ${error.stack}`);
reject(error);
}

Explanations given on previous comments already explain the issue.
I'm sharing the final code that I built and worked for me, since I needed something that worked in a more decoupled manner, instead of the way that most of the solutions presented above do.
import { FireDb } from "#services/firebase"; // = firebase.firestore();
type TDocRef = FirebaseFirestore.DocumentReference;
type TDocData = FirebaseFirestore.DocumentData;
let fireBatches = [FireDb.batch()];
let batchSizes = [0];
let batchIdxToUse = 0;
export default class FirebaseUtil {
static addBatchOperation(
operation: "create",
ref: TDocRef,
data: TDocData
): void;
static addBatchOperation(
operation: "update",
ref: TDocRef,
data: TDocData,
precondition?: FirebaseFirestore.Precondition
): void;
static addBatchOperation(
operation: "set",
ref: TDocRef,
data: TDocData,
setOpts?: FirebaseFirestore.SetOptions
): void;
static addBatchOperation(
operation: "create" | "update" | "set",
ref: TDocRef,
data: TDocData,
opts?: FirebaseFirestore.Precondition | FirebaseFirestore.SetOptions
): void {
// Lines below make sure we stay below the limit of 500 writes per
// batch
if (batchSizes[batchIdxToUse] === 500) {
fireBatches.push(FireDb.batch());
batchSizes.push(0);
batchIdxToUse++;
}
batchSizes[batchIdxToUse]++;
const batchArgs: [TDocRef, TDocData] = [ref, data];
if (opts) batchArgs.push(opts);
switch (operation) {
// Specific case for "set" is required because of some weird TS
// glitch that doesn't allow me to use the arg "operation" to
// call the function
case "set":
fireBatches[batchIdxToUse].set(...batchArgs);
break;
default:
fireBatches[batchIdxToUse][operation](...batchArgs);
break;
}
}
public static async runBatchOperations() {
// The lines below clear the globally available batches so we
// don't run them twice if we call this function more than once
const currentBatches = [...fireBatches];
fireBatches = [FireDb.batch()];
batchSizes = [0];
batchIdxToUse = 0;
await Promise.all(currentBatches.map((batch) => batch.commit()));
}
}

Based on all the above answers, I put together the following pieces of code that one can put into a module in JavaScript back-end and front-end to easily use Firestore batch writes, without worrying about the 500 writes limit.
Back-end (Node.js)
// The Firebase Admin SDK to access Firestore.
const admin = require("firebase-admin");
admin.initializeApp();
// Firestore does not accept more than 500 writes in a transaction or batch write.
const MAX_TRANSACTION_WRITES = 499;
const isFirestoreDeadlineError = (err) => {
console.log({ err });
const errString = err.toString();
return (
errString.includes("Error: 13 INTERNAL: Received RST_STREAM") ||
errString.includes("Error: 4 DEADLINE_EXCEEDED: Deadline exceeded")
);
};
const db = admin.firestore();
// How many transactions/batchWrites out of 500 so far.
// I wrote the following functions to easily use batchWrites wthout worrying about the 500 limit.
let writeCounts = 0;
let batchIndex = 0;
let batchArray = [db.batch()];
// Commit and reset batchWrites and the counter.
const makeCommitBatch = async () => {
console.log("makeCommitBatch");
await Promise.all(batchArray.map((bch) => bch.commit()));
};
// Commit the batchWrite; if you got a Firestore Deadline Error try again every 4 seconds until it gets resolved.
const commitBatch = async () => {
try {
await makeCommitBatch();
} catch (err) {
console.log({ err });
if (isFirestoreDeadlineError(err)) {
const theInterval = setInterval(async () => {
try {
await makeCommitBatch();
clearInterval(theInterval);
} catch (err) {
console.log({ err });
if (!isFirestoreDeadlineError(err)) {
clearInterval(theInterval);
throw err;
}
}
}, 4000);
}
}
};
// If the batchWrite exeeds 499 possible writes, commit and rest the batch object and the counter.
const checkRestartBatchWriteCounts = () => {
writeCounts += 1;
if (writeCounts >= MAX_TRANSACTION_WRITES) {
batchIndex++;
batchArray.push(db.batch());
writeCounts = 0;
}
};
const batchSet = (docRef, docData) => {
batchArray[batchIndex].set(docRef, docData);
checkRestartBatchWriteCounts();
};
const batchUpdate = (docRef, docData) => {
batchArray[batchIndex].update(docRef, docData);
checkRestartBatchWriteCounts();
};
const batchDelete = (docRef) => {
batchArray[batchIndex].delete(docRef);
checkRestartBatchWriteCounts();
};
module.exports = {
admin,
db,
MAX_TRANSACTION_WRITES,
checkRestartBatchWriteCounts,
commitBatch,
isFirestoreDeadlineError,
batchSet,
batchUpdate,
batchDelete,
};
Front-end
// Firestore does not accept more than 500 writes in a transaction or batch write.
const MAX_TRANSACTION_WRITES = 499;
const isFirestoreDeadlineError = (err) => {
return (
err.message.includes("DEADLINE_EXCEEDED") ||
err.message.includes("Received RST_STREAM")
);
};
class Firebase {
constructor(fireConfig, instanceName) {
let app = fbApp;
if (instanceName) {
app = app.initializeApp(fireConfig, instanceName);
} else {
app.initializeApp(fireConfig);
}
this.name = app.name;
this.db = app.firestore();
this.firestore = app.firestore;
// How many transactions/batchWrites out of 500 so far.
// I wrote the following functions to easily use batchWrites wthout worrying about the 500 limit.
this.writeCounts = 0;
this.batch = this.db.batch();
this.isCommitting = false;
}
async makeCommitBatch() {
console.log("makeCommitBatch");
if (!this.isCommitting) {
this.isCommitting = true;
await this.batch.commit();
this.writeCounts = 0;
this.batch = this.db.batch();
this.isCommitting = false;
} else {
const batchWaitInterval = setInterval(async () => {
if (!this.isCommitting) {
this.isCommitting = true;
await this.batch.commit();
this.writeCounts = 0;
this.batch = this.db.batch();
this.isCommitting = false;
clearInterval(batchWaitInterval);
}
}, 400);
}
}
async commitBatch() {
try {
await this.makeCommitBatch();
} catch (err) {
console.log({ err });
if (isFirestoreDeadlineError(err)) {
const theInterval = setInterval(async () => {
try {
await this.makeCommitBatch();
clearInterval(theInterval);
} catch (err) {
console.log({ err });
if (!isFirestoreDeadlineError(err)) {
clearInterval(theInterval);
throw err;
}
}
}, 4000);
}
}
}
async checkRestartBatchWriteCounts() {
this.writeCounts += 1;
if (this.writeCounts >= MAX_TRANSACTION_WRITES) {
await this.commitBatch();
}
}
async batchSet(docRef, docData) {
if (!this.isCommitting) {
this.batch.set(docRef, docData);
await this.checkRestartBatchWriteCounts();
} else {
const batchWaitInterval = setInterval(async () => {
if (!this.isCommitting) {
this.batch.set(docRef, docData);
await this.checkRestartBatchWriteCounts();
clearInterval(batchWaitInterval);
}
}, 400);
}
}
async batchUpdate(docRef, docData) {
if (!this.isCommitting) {
this.batch.update(docRef, docData);
await this.checkRestartBatchWriteCounts();
} else {
const batchWaitInterval = setInterval(async () => {
if (!this.isCommitting) {
this.batch.update(docRef, docData);
await this.checkRestartBatchWriteCounts();
clearInterval(batchWaitInterval);
}
}, 400);
}
}
async batchDelete(docRef) {
if (!this.isCommitting) {
this.batch.delete(docRef);
await this.checkRestartBatchWriteCounts();
} else {
const batchWaitInterval = setInterval(async () => {
if (!this.isCommitting) {
this.batch.delete(docRef);
await this.checkRestartBatchWriteCounts();
clearInterval(batchWaitInterval);
}
}, 400);
}
}
}

No citations or documentation, this code i invented by myself and for me it worked and looks clean, and simple for read and usage. If some one like it, then can use it too.
Better make autotest becose code use private var _ops wich can be changed after packages upgrade. Forexample in old versions its can be _mutations
async function commitBatch(batch) {
const MAX_OPERATIONS_PER_COMMIT = 500;
while (batch._ops.length > MAX_OPERATIONS_PER_COMMIT) {
const batchPart = admin.firestore().batch();
batchPart._ops = batch._ops.splice(0, MAX_OPERATIONS_PER_COMMIT - 1);
await batchPart.commit();
}
await batch.commit();
}
Usage:
const batch = admin.firestore().batch();
batch.delete(someRef);
batch.update(someRef);
...
await commitBatch(batch);

Simple solution
Just fire twice ?
my array is "resultsFinal"
I fire batch once with a limit of 490 , and second with a limit of the lenght of the array ( results.lenght)
Works fine for me :)
How you check it ?
You go to firebase and delete your collection , firebase say you have delete XXX docs , same as the lenght of your array ? Ok so you are good to go
async function quickstart(results) {
// we get results in parameter for get the data inside quickstart function
const resultsFinal = results;
// console.log(resultsFinal.length);
let batch = firestore.batch();
// limit of firebase is 500 requests per transaction/batch/send
for (i = 0; i < 490; i++) {
const doc = firestore.collection('testMore490').doc();
const object = resultsFinal[i];
batch.set(doc, object);
}
await batch.commit();
// const batchTwo = firestore.batch();
batch = firestore.batch();
for (i = 491; i < 776; i++) {
const objectPartTwo = resultsFinal[i];
const doc = firestore.collection('testMore490').doc();
batch.set(doc, objectPartTwo);
}
await batch.commit();
}