Get Time to first byte from API Groovy

Question

I am writing a script to get TTFB for an URL. This getResponseCode method gives me status code for the URL. What method or formula can I use to get TTFB after connection is established?

HttpURLConnection connection

    try {
        
            URL url = new URL('www.xyx.com')
            connection = (HttpURLConnection)url.openConnection()
            connection.setRequestMethod("GET")
            connection.connect()

            println(connection.getResponseCode())
        
    }
    catch(Exception ex) {
        return 0
    }
    finally {
        connection.disconnect()
                    }

What exactly you don't know? How to measure time? Or how to get first byte from stream? — daggett, Jun 30 '21 at 20:37
How can I get TTFB using a program? I can see TTFB in chrome devtools but I want it as the output from my program. Is there a method in connection library ? — Surbhi, Jun 30 '21 at 21:08
can I calculate is using existing methods or get it from devtools somehow? — Surbhi, Jun 30 '21 at 22:04

score 0 · Answer 1 · answered Jul 01 '21 at 04:09

0

The obvious way

long t0 = System.getTimeMillis()
connection.getInputStream()?.read()
long t1 = System.getTimeMillis()

long ttfb = t1 - t0

However I'm not sure about accuracy...

answered Jul 01 '21 at 04:09

daggett

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Retrieving the stream (`getInputStream()`) probably shouldn't be done inside the timer. The same thing for the null check. – Jeff Scott Brown Jul 06 '21 at 23:28
Probably you are right. I would wrap it into @CompileStatic to minimize dynamic groovy latency. – daggett Jul 07 '21 at 04:15
"I would wrap it into @CompileStatic to minimize dynamic groovy latency." - If you did, I still think it makes sense to call `getInputStream()` and do any null checking before the timer starts. – Jeff Scott Brown Jul 07 '21 at 13:01

Get Time to first byte from API Groovy

1 Answers1