config

Overview ¶

Package config provides parser for cloudprober configs.

Example Usage:

c, err := config.Parse(*configFile, sysvars.SysVars())

Parse processes a config file as a Go text template and parses it into a ProberConfig proto. Config file is processed using the provided variable map (usually GCP metadata variables) and some predefined macros.

Cloudprober configs support following macros:

*) mkSlice - mkSlice returns a slice consisting of arguments. Example use in config:

# Sharded VM-to-VM connectivity checks over internal IP
# Instance name format: ig-<zone>-<shard>-<random-characters>, e.g. ig-asia-east1-a-00-ftx1

{{with $shards := mkSlice "00" "01" "02" "03"}}
{{range $_, $shard := $shards}}
{{$targets := printf "^ig-([^-]+-[^-]+-[^-]+)-%s-[^-]+$" $shard}}
{{$run_on := printf "^ig-([^-]+-[^-]+-[^-]+)-%s-[^-.]+(|[.].*)$" $shard}}

probe {
	name: "vm-to-vm-{{$shard}}"
	type: PING
	targets {
		gce_targets {
			instances {}
		}
		regex: "{{$targets}}"
	}
	run_on: "{{$run_on}}"
}

*) extractSubstring - extract substring from a string using regex. Example use in config:

# Sharded VM-to-VM connectivity checks over internal IP
# Instance name format: ig-<zone>-<shard>-<random-characters>, e.g. ig-asia-east1-a-00-ftx1
{{$shard := .instance | extractSubstring "[^-]+-[^-]+-[^-]+-[^-]+-([^-]+)-.*" 1}}
probe {
	name: "vm-to-vm-{{$shard}}"
	type: PING
	targets {
		gce_targets {
			instances {}
		}
		regex: "{{$targets}}"
	}
	run_on: "{{$run_on}}"
}