Error parsing XML from BIND 9.16.11

[0gcr]

$ uname -mrs
FreeBSD 12.1-RELEASE-p13 amd64

$ pkg info --comment go git bind
go-1.15.7,1 Go programming language
git-2.30.0 Distributed source code management tool
bind916-9.16.11 BIND DNS suite with updated DNSSEC and DNS64

$ named -v
BIND 9.16.11 (Stable Release) id:9ff601b

$ go get github.com/prometheus-community/bind_exporter && ~/go/bin/bind_exporter --bind.stats-url=http://localhost:8053
level=info ts=2021-01-31T07:06:44.622Z caller=bind_exporter.go:529 msg="Starting bind_exporter" version="(version=, branch=, revision=)"
level=info ts=2021-01-31T07:06:44.622Z caller=bind_exporter.go:530 msg="Build context" build_context="(go=go1.15.7, user=, date=)"
level=info ts=2021-01-31T07:06:44.622Z caller=bind_exporter.go:531 msg="Collectors enabled" collectors=server,view,tasks
level=info ts=2021-01-31T07:06:44.623Z caller=bind_exporter.go:555 msg="Listening on" address=:9119
level=info ts=2021-01-31T07:06:44.623Z caller=tls_config.go:191 msg="TLS is disabled." http2=false
level=error ts=2021-01-31T07:06:48.806Z caller=bind_exporter.go:427 msg="Couldn't retrieve BIND stats" err="failed to unmarshal XML response: strconv.ParseUint: parsing "-": invalid syntax"
level=error ts=2021-01-31T07:07:03.869Z caller=bind_exporter.go:427 msg="Couldn't retrieve BIND stats" err="failed to unmarshal XML response: strconv.ParseUint: parsing "-": invalid syntax"
level=error ts=2021-01-31T07:07:18.895Z caller=bind_exporter.go:427 msg="Couldn't retrieve BIND stats" err="failed to unmarshal XML response: strconv.ParseUint: parsing "-": invalid syntax"
^C

See sample XML output.

[tribor]

same problem for me with
BIND 9.11.4-P2-RedHat-9.11.4-26.P2.el7 (Extended Support Version) <id:7107deb>

[Ben Kochie]

Thanks for the report. Any interest in working on a patch?

[ggulchin]

Hi! is there an update?

[0gcr]

Thanks for the report. Any interest in working on a patch?

As much as I'd like to be able to do that, I'm afraid this is beyond my current skill set.

[opsman78]

We have the same problem. Is there any update on this?

[Lauritz Leifermann]

Hey I've taken a look at this, and it seems that the Bind Server returns a non integer Value for the XML as seen in the sample XML Output mentioned above:

I think this then gets deserialized or unmarshaled onto a ZoneCounter Struct, which expects this value to be a uint64

type ZoneCounter struct {
	Name       string `xml:"name,attr"`
	Rdataclass string `xml:"rdataclass,attr"`
	Serial     uint64 `xml:"serial"`
}

I am taking a closer look now, but i can't promise a patch right now.

[Lauritz Leifermann]

@SuperQ would it be okay to implement a custom unmarshal function for the Zonestruct? I think bind really does not fullfill its specification here. With the custom unmarshaling function, we can just differentiate anything that is not an int for the serial xml field.

[Ben Kochie]

I guess we need to change the Serial to a string, and then add some strconv.ParseUint() handling around it.

[Ben Kochie]

This is fixed.