fix: http keep alive now works

[Mall0c]

Thank you for this simple yet great library.

I am using this library for debugging purposes. I have added a custom HTTP Agent to superagent, because I'd like to use HTTP Keep-Alive. I am issuing many requests per second to the same server and establishing a new TCP connection every time is a waste of ressources.

The HTTP agent is created as simple as this example:

new http.Agent({
    keepAlive: true
})

and then provided to superagent with the .agent() method:

superagent
	.get("foobar")
    .use(logNetworkTime((err, result) => {
        if (err) {
            console.log(err)
        } else {
            console.log(timing)
        }
    }))
    .send("json obj")
    .timeout(30000)
    .set("Content-Type", "application/json")
    .set("Accept", "application/json")
    .auth("user", "pass")
    .agent(globalThis.HttpAgent)

This would give me the following exception:

/path/to/app/node_modules/superagent-node-http-timings/index.js:78
  const secondDiff = endTime[0] - startTime[0];
                                           ^
TypeError: Cannot read properties of undefined (reading '0')
    at getHrTimeDurationInMs (/path/to/app/node_modules/superagent-node-http-timings/index.js:78:44)
    at getTimings (/path/to/app/node_modules/superagent-node-http-timings/index.js:68:16)
    at IncomingMessage.<anonymous> (/path/to/app/node_modules/superagent-node-http-timings/index.js:44:22)
    at Stream.emit (node:events:531:35)
    at Unzip.<anonymous> (/path/to/app/node_modules/superagent/src/node/unzip.js:55:12)
    at Unzip.emit (node:events:519:28)
    at endReadableNT (node:internal/streams/readable:1696:12)
    at process.processTicksAndRejections (node:internal/process/task_queues:82:21)

After some debugging I found out its due to the HTTP Keep Alive flag. The agent maintains a pool of reusable TCP connections to the server I'm talking to. That means, there is no tcpConnectionAt variable, since there is no connect event on subsequent HTTP requests.

I have provided a fix.

[webuniverseio]

Thanks a lot!

[webuniverseio]

I'll look into updating npm package version next Monday.

[webuniverseio]

@Mall0c 1.0.2 is now published 🥳 🙌

https://github.com/webuniverseio/superagent-node-http-timings/releases/tag/v1.0.2
https://www.npmjs.com/package/superagent-node-http-timings