Memcached unix socket panic

[tdewolff]

I have configured memcached as

# Read metrics from one or many memcached servers
[[inputs.memcached]]
  ## An array of address to gather stats about. Specify an ip on hostname
  ## with optional port. ie localhost, 10.0.0.1:11211, etc.
  # servers = ["localhost:11211"]
  unix_sockets = ["/var/run/memcached/memcached.sock"]

But this throws the following panic:

panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xb code=0x1 addr=0x40 pc=0x56e61b]

goroutine 1 [running]:
github.com/influxdata/telegraf/plugins/inputs/memcached.(*Memcached).gatherServer(0xc8200c3950, 0xc8200c38c1, 0x21, 0xc8200c8101, 0x7f4120b25340, 0xc82004af00, 0x0, 0x0)
        /home/ubuntu/telegraf-build/src/github.com/influxdata/telegraf/plugins/inputs/memcached/memcached.go:117 +0x1fb
github.com/influxdata/telegraf/plugins/inputs/memcached.(*Memcached).Gather(0xc8200c3950, 0x7f4120b25340, 0xc82004af00, 0x0, 0x0)
        /home/ubuntu/telegraf-build/src/github.com/influxdata/telegraf/plugins/inputs/memcached/memcached.go:83 +0x261
github.com/influxdata/telegraf/agent.(*Agent).Test(0xc820028000, 0x0, 0x0)
        /home/ubuntu/telegraf-build/src/github.com/influxdata/telegraf/agent/agent.go:228 +0x434
main.main()
        /home/ubuntu/telegraf-build/src/github.com/influxdata/telegraf/cmd/telegraf/telegraf.go:190 +0x120e

The file /var/run/memcached/memcached.sock exists and has 766 memcached:memcached permissions.

[sparrc]

thanks for the report, it looks like we were overwriting our own net connection within an if statement that was going out of scope. This will be fixed in the next release.