Postman: how to send asynchronous request by script - postman

Question

I got two requests: A and B in postman. I want to send the request A first then send the request B while request A is still waiting for the response. It's quite easy to do this mannually because request A take 15s to finish.
But are there anyway I can do this automatically, because I am going to test this case a lot.
I have tried to use runner in postman but it always wait for request A to be finish before sending request B.
After that I found a document about sending asynchronous request in postman here.
I wrote a script that use pm.sendRequest to send request B and put that script in the pre-request of request A.
let confirmRequest = {
url: url + "/confirm",
method: "POST",
body: {
"requestId": (new Date()).getTime(),
"statusCode": "0",
}
}
setTimeout(function() {
pm.sendRequest(confirmRequest, function (err, res) {
console.log(err ? err : res.json());
});
}, 1500);
the problem is even I've wrapped it inside a setTimeout function, the request A still wait for pre-request to finish first. So in the end request B have been send before request A.
Are there any solution to this problem?

Answer 1

I tried but could not achieve asynchronously process requests using Postman or Newman. I found it easier to write a nodeJS code using async-await-promise concepts. Here is the sample code:
Sample Code that works for me:
var httpRequest "your raw request body";
var headersOpt = {
"content-type": "application/json",
};
const promisifiedRequest = function(options) {
return new Promise((resolve,reject) => {
request(options, (error, response, body) => {
if (response) {
return resolve(response);
}
if (error) {
return reject(error);
}
});
});
};
var output;
async function MyRequest(httpRequest,j, fileName) {
var options = {
uri: "url",
method: "POST",
body: httpRequest,
json: true,
time: true,
headers: headersOpt
}
try {
console.log('request posted!');
let response = await promisifiedRequest(options);
console.log('response recieved!');
output = output + ',' +response.elapsedTime;
console.log(response.elapsedTime);
console.log(output);
//return response;
} catch (err) {
console.log(err);
}
finally
{
//this code is optional and it used to save the response time for each request.
try{
fileName = (j+1)+'_'+fileName;
fs.writeFile('/logs-async/scripts/output/'+fileName+'.csv', output, (err) => {
//throws an error, you could also catch it here
if (err) throw err;
});
}
catch (err){
console.log(err);
}
}
}