AWS Lambda not calling third party api in loop - node.js

Question

i am using aws lambda and i am calling third party server using request library. this library on outside the loop but on loop its not hitting even i am not getting any error or result. and i also checked on server there is no hitting
below is my code with console
exports.handler = async (event) => {
try {
let transactionList = [];
// event.body is json form object with keys and values that we send
userBrokers.forEach(async (brokers) => {
const userStocks = 50;
const qty = (qtyPercentage * userStocks) / 100;
console.log("function before api call")
request.post({
headers: {
'content-type': 'application/x-www-form-urlencoded',
"Apca-Api-Key-Id": brokers.api_key,
"Apca-Api-Secret-Key": brokers.secret_key
},
url: 'https://paper-api.alpaca.markets/v2/orders',
json: {
symbol,
qty,
side: orderType,
type: marketType,
time_in_force
}
}, function (error, response, body) {
if (error) {
console.log("api call error")
transactionList.push({
transactionSuccess: false,
reason: error,
userId: brokers.user_id,
documentId: brokers._id
})
}
else {
console.log("api response")
if (response.statusCode == 200) {
transactionList.push({
brokerOrderId: body.id,
symbol: body.symbol,
orderType: body.order_type,
marketType: body.side,
transactionSuccess: true,
userId: brokers.user_id,
documentId: brokers._id
})
}
else {
transactionList.push({
transactionSuccess: false,
reason: body.message,
userId: brokers.user_id,
documentId: brokers._id
})
}
}
});
})
console.log("function before response")
return {
statusCode: 200,
body: JSON.stringify(transactionList),
};
} catch (error) {
console.log("function catch block")
return {
statusCode: 200,
body: JSON.stringify(error.message),
};
}};
and i get below console.
function before api call
function before response
and response from lambda
status: 200 and message: []

Answer 1

The problem is that you're trying to execute an async method in a forEach but you have no way of enforcing Lambda to wait for the loop to finish. You should switch your forEach to a map and await all the promises:
Bad:
arr.forEach(async (val) => {})
Good:
const arrOfResults = await Promise.all(arr.map(async (val) => {}))