Benchmark express apis with autocannon from postman collection - node.js

Question

I need to benchmark all my express apis.
I found this package on github. Examples are listed only for one get request.
There are also some other samples for other requests as well.
I want to know should I create a separate script for all the APIs and run them once.
I already have a postman collection for all the APIs. Is there any way I can use that to benchmark them?
If there is any other way to benchmark express APIs, please suggest.
Update
const autocannon = require("autocannon");
const fs = require("fs");
const collection = JSON.parse(fs.readFileSync("./customer-apis-v1.3.2.json", "UTF-8"));
const requests = collection.item;
(async function test() {
for (const request of requests) {
console.log(`Testing ${request.name}`);
for (const item of request.item) {
const result = await autocannon({
title: item.name,
url: item.request.url.raw,
method: item.request.method,
});
autocannon.printResult(result);
}
}
})().catch((error) => console.log(error));

Answer 1

You can export your Postman Collection as JSON.
Right Click on the collection
Click export
Choose Collection type
Click export
The exported file will be a .json file and will look like this:
{
"info": {
"_postman_id": "...",
"name": "...",
"schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json"
},
"item": [
{
"name": "name",
"request": {
"method": "GET",
"header": [],
"url": {
"raw": "http://...",
"protocol": "http",
"host": [
...
],
"path": [
...
],
"query": [
{
"key": "...",
"value": "..."
}
]
}
},
"response": []
}
],
"protocolProfileBehavior": {}
}
Then you can use autocannon programatically and read the json file
const autocannon = require("autocannon");
const fs = require("fs");
// read array of items from exported .json file from postman
const requests = JSON.parse(fs.readFileSync("path/to/postman/exported.json", "UTF-8")).items;
async function test() {
for (const item of requests) {
// test request using autocannon, pass the method, body, etc. on the autocannon options
// you might need to manipulate your data in item so you can pass it to autocannon
console.log(`Testing ${item.name}`);
const result = await autocannon({
url: item.request.url.raw,
method: item.request.method,
... // read other options here: https://github.com/mcollina/autocannon#autocannonopts-cb
})
console.log(result);
// or print table
autocannon.printResult(result);
}
}
You can also do it without await
The other way is to use Postman built-in Testing utility
Right click on the collection
Click Edit
Click Tests tab
Write your test script there
Doc about writing test: https://learning.postman.com/docs/writing-scripts/test-scripts/
Doc about monitoring test performance: https://learning.postman.com/docs/designing-and-developing-your-api/monitoring-your-api/intro-monitors/