tsmon: read hostname and region from config file

common/tsmon/iface.go

Index: common/tsmon/iface.go
diff --git a/common/tsmon/iface.go b/common/tsmon/iface.go
index 90559043aec0eb76fb554a9a685b9e45b0d6cb32..d9a0f548a54d6b7201900acc9533b62562f674bd 100644
--- a/common/tsmon/iface.go
+++ b/common/tsmon/iface.go
@@ -99,6 +99,14 @@ func InitializeFromFlags(c context.Context, fl *Flags) error {
 	if config.AutoGenHostname {
 		fl.Target.AutoGenHostname = true
 	}
+	if config.Hostname != "" {
+		fl.Target.DeviceHostname = config.Hostname

[dsansome, 2016/08/09 03:28:22]

I would expect flags to override values from a config file?

if config.Hostname != "" {
  if fl.Target.DeviceHostname == "" {
    fl.Target.DeviceHostname = config.Hostname
  }
  ...
}

Same for AutoGenHostname above actually.

[Sergey Berezin, 2016/08/10 01:49:16]

Good catch, thanks! Done.
For AutoGenHostname, it'll be set to true when either config or command line
flag sets it. I think this is still an expected behavior.

+		fl.Target.TaskHostname = config.Hostname
+	}
+	if config.Region != "" {
+		fl.Target.DeviceRegion = config.Region
+		fl.Target.TaskRegion = config.Region
+	}
 	fl.Target.SetDefaultsFromHostname()
 	t, err := target.NewFromFlags(&fl.Target)
 	if err != nil {