http resp.Write & httputil.DumpResponse include extra text with body

Peter Galbavy

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Sep 13, 2024, 9:10:05 AM9/13/24

to golang-nuts

I am trying to add some low level tracing to a client app to validate the responses coming from a SaaS platform.

When I use either http's resp.Write(os.Stderr) or httputil.DumpResponse(resp, true) I see a hex content length immediately before the body and a literal "0" on a line after,

i.e. using a local copy of the doc example for DumpResponse() but with a real URL and outputting "string(dump)" instead of quotes bytes) to a local server I get (HTML between open/close removed for brevity):

---
HTTP/1.1 200 OK
Transfer-Encoding: chunked
Connection: keep-alive
Content-Type: text/html
Date: Fri, 13 Sep 2024 13:05:33 GMT
Etag: W/"62136b7a-d2"
Last-Modified: Mon, 21 Feb 2022 10:37:46 GMT
Server: nginx/1.27.0

d2
<!DOCTYPE HTML>
<html>
...
</html>

0

---

The "d2" is the content length and the "0" is extra. Compared against Postman and curl on the command line, to be sure.

Is this expected by undocumented or have I missed something please?

Eli Lindsey

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Sep 13, 2024, 9:25:19 AM9/13/24

to Peter Galbavy, golang-nuts

Those are sizes from chunked encoding.

-eli

On Sep 13, 2024, at 9:10 AM, Peter Galbavy <pe...@wonderland.org> wrote:

I am trying to add some low level tracing to a client app to validate the responses coming from a SaaS platform.

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Peter Galbavy

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Sep 13, 2024, 9:37:50 AM9/13/24

to golang-nuts

Makes sense and good to know, but for diag output is there any way to turn it off?

Robert Engels

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Sep 13, 2024, 9:43:49 AM9/13/24

to Peter Galbavy, golang-nuts

If you set the content length in the header it should turn off chunked encoding.

On Sep 13, 2024, at 8:38 AM, Peter Galbavy <pe...@wonderland.org> wrote:

Makes sense and good to know, but for diag output is there any way to turn it off?

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Eli Lindsey

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Sep 13, 2024, 9:54:03 AM9/13/24

to Peter Galbavy, golang-nuts

DumpResponse is intended for debugging output, so it’s important for it to surface the chunked encoding. If you want to automatically dechunk, you can use higher level APIs - NewChunkedReader() handles dechunking, and is used internally by transport.

-eli

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