loki.river

logging {
	level  = "debug"
	format = "logfmt"

	// Soon™
	// write_to = loki.write.grafanacloud.receiver
}

/* CRI-formatted log lines.
I'm cheating and just redirecting from stdin for the demo :sweat_smile: */
discovery.file "tmp" {
	path_targets = [{"__path__" = "/tmp/mylogfiles/**/*.log"}]
}

loki.source.file "tmpfiles" {
	targets    = discovery.file.tmp.targets
	forward_to = [loki.process.crio.receiver]
}

loki.process "crio" {
	stage {
		cri { }
	}

	/* 2023-01-01T00:02:17.9143717Z stdout F level=WARN duration=125 message="something happened" foo=bar
	extracts:
		timestamp: 2023-01-01T00:02:17.9143717Z
		stream: stdout
		flags: F
		content: level=WARN duration=125 message="something happened" foo=bar
	*/

	// syntax will change to stage.cri, stage.logfmt etc
	stage {
		logfmt {
			source  = "content"
			mapping = {lvl = "level", msg = "message"}
		}
	}

	/* The extracted map now also contains:
		lvl: "WARN"
		msg: "something happened"
	*/

	stage {
		labels {
			values = {loglevel = "lvl"}
		}
	}

	stage {
		static_labels {
			values = {hostname = env("HOSTNAME"), source = "logfile"}
		}
	}

	stage {
		output {
			source = "msg"
		}
	}

	forward_to = [loki.write.grafanacloud.receiver, loki.stdout.debug.receiver]
}

/* Syslog messages and OTel logs */

loki.source.syslog "tcp" {
	listener {
		address  = "127.0.0.1:51893"
		protocol = "tcp"

		labels = {source = "syslog", protocol = "tcp"}
	}

	forward_to = [loki.relabel.add_hostname.receiver]
}

otelcol.receiver.otlp "default" {
	http { }

	output {
		logs = [otelcol.exporter.loki.default.input]
	}
}

otelcol.exporter.loki "default" {
	forward_to = [loki.relabel.add_hostname.receiver]
}

loki.relabel "add_hostname" {
	rule {
		action       = "replace"
		target_label = "hostname"
		replacement  = env("HOSTNAME")
	}

	forward_to = [loki.write.grafanacloud.receiver, loki.stdout.debug.receiver]
}

// Not merged component, only for demo purposes
loki.stdout "debug" { }

/* Send to Loki */
loki.write "grafanacloud" {
	endpoint {
		url = "<loki_url>"

		http_client_config {
			basic_auth {
				username      = "<username>"
				password_file = "/tmp/token.txt"
			}
		}
	}
}