Concurrency issue in http.go

[miekg]

The call in https://github.com/prometheus/client_golang/blob/master/prometheus/http.go#L146

go computeApproximateRequestSize(r, out, urlLen)

creates concurrency issues because it iterates on request's Header map, if (for some reason) you happen to call this function more than once.

[beorn7]

The header map is only read in the function. Is there any code path where the request header map is modified?

[juliusv]

@miekg ping

[miekg]

[ Quoting [email protected] in "Re: [client_golang] Concurrency iss..." ]

@miekg ping

This might be us doing whacky things, while this is being called. We basically
hacked around this, but not using these wrappers (that eventually call this
function) anymore.

Can't guarantee I can find enough time to properly debug this.

Close it?

/Miek

Miek Gieben

[beorn7]

I'll close it then. Please re-open if you find evidence.