how to debug a specific api in golang?

Question

my wired situation is, the online service is working now, and everyday i can find a few 500 error reports like below:

2018-12-19 00:00:01     [ERROR] path[/vplay/getIdsInfo/?type=vlist&ids=31105228] err[runtime error: index out of range] stack[
goweb.(*RouterTab).ServeHTTP.func3.1:/home/tanxiaolong/golib/src/goweb/router.go:352
runtime.call64:/usr/local/go/src/runtime/asm_amd64.s:574
runtime.gopanic:/usr/local/go/src/runtime/panic.go:505
runtime.panicindex:/usr/local/go/src/runtime/panic.go:28
models.(*VplayModel).AssembleData:/home/tanxiaolong/golib/src/vplay/models/vplay.go:757
controllers.(*VplayController).GetIdsInfoAction:/home/tanxiaolong/golib/src/vplay/controllers/vplay.go:652
runtime.call32:/usr/local/go/src/runtime/asm_amd64.s:573
reflect.Value.call:/usr/local/go/src/reflect/value.go:447
reflect.Value.Call:/usr/local/go/src/reflect/value.go:308
goweb.(*RouterTab).ServeHTTP.func3:/home/tanxiaolong/golib/src/goweb/router.go:370
runtime.goexit:/usr/local/go/src/runtime/asm_amd64.s:2361]      (goweb/router.go:353)

i can find which api by log, but it returns 200 and correct response data if request it with the same query data as 500 requests by myself or wrk or ab.

i don't know how to debug this bug..

any suggestions on api debugging??

many thanks!

from the stack trace it's clear that the panic happen on router.go:352. we still need the code. not just the stack trace. — novalagung
– novalagung, Commented Dec 19, 2018 at 4:24
i found that bug along with the stack tips~ thank your tips too! — touchstone
– touchstone, Commented Dec 19, 2018 at 4:52

Martin · Accepted Answer · 2018-12-19 04:07:49Z

2

When you're handling errors you can use:

err.(*errors.Error).ErrorStack()

to return the stacktrace. With that you can get the line in which your API in some cases gets an index out of range error.

answered Dec 19, 2018 at 4:07

Martin

1,17111 silver badges23 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

touchstone Over a year ago

i used a error stack print,and i pick the one i understand attached. :-P i dont know why i curl the api with 200 returns and the online service is sometime 500 returns. i doubt that the online requests mess the goroutines up, but i have no proofs..

Martin Over a year ago

Nice, now we need the file vplay.go in the line 652 and everything related to it.

touchstone Over a year ago

ah, i found the bug~ indeed a index out of a slice. thank you so much!

Collectives™ on Stack Overflow

how to debug a specific api in golang?

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related