How can I read consul SRV records in my go application?

Question

I am trying to implement consul for service discovery, and I am having trouble with two things: connecting to a custom DNS server, and formatting my net.LookupSRV() request.

Here is what I'm trying to look up from within my go app:

$ dig @127.0.0.1 -p 8600 serviceb.service.consul SRV

; <<>> DiG 9.8.4-rpz2+rl005.12-P1 <<>> @127.0.0.1 -p 8600 serviceb.service.consul SRV
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4511
;; flags: qr aa rd; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 2
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;serviceb.service.consul.   IN  SRV

;; ANSWER SECTION:
serviceb.service.consul. 0  IN  SRV 1 1 80 az1-serviceb1.node.dc1.consul.
serviceb.service.consul. 0  IN  SRV 1 1 80 az2-serviceb2.node.dc1.consul.

;; ADDITIONAL SECTION:
az1-serviceb1.node.dc1.consul. 0 IN A   10.6.41.22
az2-serviceb2.node.dc1.consul. 0 IN A   10.6.41.20

;; Query time: 6 msec
;; SERVER: 127.0.0.1#8600(127.0.0.1)
;; WHEN: Fri May 16 15:09:28 2014
;; MSG SIZE  rcvd: 275

and here is the relevant code. (I know it's wrong, but just so you can see what I'm trying to do)

cname, addrs, err := net.LookupSRV("serviceb", "service", "consul")
log.Printf("%+v %+v %+v", cname, addrs, err)

and the output:

2014/05/16 15:24:31  [] lookup _serviceb._service.consul: no such host

Any help would be appreciated! thanks

Answer 1

Try to use a more sharp tool such as the github.com/miekg/dns package. Last time I looked at it, it allowed to control virtually every bit of the client-side setup to do DNS resolution.