Storage snapshot: optional skipHead parameter not optional

[beorn7]

Bug Report

What did you do?

$ curl -XPOST http://localhost:9090/api/v1/admin/tsdb/snapshot

What did you expect to see?

{"status":"success","data":{"name":"20181012T143717Z-655852ac65b7132f"}}

What did you see instead? Under which circumstances?

{"status":"error","errorType":"unavailable","error":"unable to parse boolean 'skip_head' argument: strconv.ParseBool: parsing \"\": invalid syntax"}

Work around

Explicitly specify the "optional" parameter:

$ curl -XPOST http://localhost:9090/api/v1/admin/tsdb/snapshot?skip_head=false

Environment

• Prometheus version:

prometheus, version 2.4.2 (branch: HEAD, revision: c305ffaa092e94e9d2dbbddf8226c4813b1190a0)
  build user:       root@dcde2b74c858
  build date:       20180921-07:22:29
  go version:       go1.10.3

[brian-brazil]

Dupe of #4671, this is fixed in 2.4.3.

[beorn7]

Ooops. Sorry for the noise. I foolishly assumed to have the state of this repo in my head.

[brian-brazil]

Don't worry about it, it happens to us all.