prometheus-node-exporter-ucode: add a plugin for go2rtc metrics

- Add a plugin to export go2rtc metrics

Requires additional api_url option to enable:

```
uci set prometheus-node-exporter-ucode.go2rtc=collector
uci set prometheus-node-exporter-ucode.go2rtc.api_url='http://127.0.0.1:1984'
```

Co-authored-by: Andre Heider <[email protected]>
Signed-off-by: Vladimir Ermakov <[email protected]>

Author: vooon

utils/prometheus-node-exporter-ucode/Makefile

@@ -4,7 +4,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=prometheus-node-exporter-ucode
 PKG_VERSION:=2024.02.07
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_MAINTAINER:=Andre Heider <[email protected]>
 PKG_LICENSE:=Apache-2.0
@@ -72,3 +72,4 @@ $(eval $(call Collector,snmp6,snmp6 collector,))
 $(eval $(call Collector,uci_dhcp_host,UCI DHCP host collector,))
 $(eval $(call Collector,wifi,Wi-Fi collector,+ucode-mod-nl80211))
 $(eval $(call Collector,wireguard,Wireguard collector,+rpcd-mod-wireguard))
+$(eval $(call Collector,go2rtc,go2rtc collector,+ucode-mod-uclient +ucode-mod-uloop go2rtc))

utils/prometheus-node-exporter-ucode/files/extra/go2rtc.uc

@@ -0,0 +1,106 @@
+import * as log from "log";
+let uloop = require("uloop");
+let uclient = require("uclient");
+
+const api_url = config["api_url"];
+if (!api_url)
+	return false;
+
+let m_up = gauge("go2rtc_up");
+let m_producer_info = gauge("go2rtc_producer_info");
+let m_consumer_info = gauge("go2rtc_consumer_info");
+let m_producer_rx = counter("go2rtc_producer_received_bytes_total");
+let m_consumer_tx = counter("go2rtc_consumer_sent_bytes_total");
+
+
+function get_streams_info(api_url) {
+	let data = '';
+
+	const url = `${api_url}/api/streams`;
+
+	uloop.init();
+	uc = uclient.new(url, null, {
+		data_read: (cb) => {
+			let chunk;
+			while (length(chunk = uc.read()) > 0)
+				data += chunk;
+		},
+		data_eof: (cb) => {
+			uloop.end();
+		},
+		error: (cb, code) => {
+			log.ERR(`failed to get url: ${url}: ${code}`);
+			data = null;
+			uloop.end();
+		}
+	});
+
+	if (!uc.set_timeout(5000)) {
+		log.ERR("failed to set timeout");
+		return null;
+	}
+
+	if (!uc.ssl_init({verify: false})) {
+		log.ERR("failed to initialize SSL");
+		return null;
+	}
+
+	if (!uc.connect()) {
+		log.ERR("failed to connect");
+		return null;
+	}
+
+	if (!uc.request("GET", {headers: {"User-Agent": "prometheus-node-exporter-ucode/1.0"}})) {
+		log.ERR("failed to send request");
+		return null;
+	}
+
+	uloop.run();
+
+	if (data == null) {
+		return null;
+	}
+
+	return json(data);
+}
+
+const x = get_streams_info(api_url);
+
+if (!x) {
+	m_up({url: api_url}, 0);
+	return false;
+}
+
+m_up({url: api_url}, 1);
+
+for (let stream, info in x) {
+
+	for (let producer in info.producers) {
+		m_producer_info({
+			stream: stream,
+			format_name: producer.format_name,
+			protocol: producer.protocol,
+			remote_addr: producer.remote_addr,
+			user_agent: producer.user_agent,
+		}, (!producer.remote_addr) ? 0 : 1);
+		m_producer_rx({
+			stream: stream,
+			remote_addr: producer.remote_addr,
+		}, producer.bytes_recv);
+	}
+
+	for (let consumer in info.consumers) {
+		m_consumer_info({
+			stream: stream,
+			format_name: consumer.format_name,
+			protocol: consumer.protocol,
+			remote_addr: consumer.remote_addr,
+			user_agent: consumer.user_agent,
+		}, 1);
+		m_consumer_tx({
+			stream: stream,
+			remote_addr: consumer.remote_addr,
+		}, consumer.bytes_send);
+	}
+
+}

utils/prometheus-node-exporter-ucode/files/init

@@ -40,10 +40,11 @@ start_service() {
 	[ $keepalive -gt 0 ] && procd_append_param command -k $keepalive
 
 	procd_add_jail prometheus-node-exporter-ucode log procfs sysfs ubus
-	procd_add_jail_mount "/usr/lib/uhttpd_ucode.so"
 	procd_add_jail_mount "/lib/libubus.so*"
 	procd_add_jail_mount "/lib/libuci.so*"
-	procd_add_jail_mount "/usr/lib/ucode"
+	procd_add_jail_mount "/lib/libustream-ssl.so"
+	procd_add_jail_mount "/usr/lib/uhttpd_ucode.so"
+	procd_add_jail_mount "/usr/lib/ucode/*.so"
 	procd_add_jail_mount "/usr/lib/libnl*.so*"
 	procd_add_jail_mount "/usr/share/ucode/node-exporter"
 	procd_add_jail_mount "/etc/config"