Init DEV commit (#1)

Init dev commit

Add README.md

Add README.md

Co-authored-by: Роман <rorudzhov@mac.local>

.gitignore

@@ -20,3 +20,6 @@
 # Go workspace file
 go.work
 go.work.sum
+
+
+build.sh

README.md

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+# Prometheus WireGuard Exporter
+
+A Prometheus exporter for [WireGuard](https://www.wireguard.com), written in GoLang. This tool execute command `sudo /usr/bin/wg show all dump` and parse results in a format [OpenMetrics](https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md) that [Prometheus](https://prometheus.io/) can understand.
+
+### Metrics
+
+All metrics are aveliable on `/metrics` path. As example you can use `curl 127.0.0.1:9172/metrics`
+
+```ebnf
+# HELP wireguard_keep_alive Number of keep alive seconds
+# TYPE wireguard_keep_alive gauge
+wireguard_keep_alive{ifname="wg0",publicKey="5CL0j1HMDxK0ftLz2ANXaZ5w2y5aOe9dV3tKF4llhlI="} 5
+# HELP wireguard_last_handshake Timestamp of last handshake
+# TYPE wireguard_last_handshake counter
+wireguard_last_handshake{ifname="wg0",publicKey="5CL0j1HMDxK0ftLz2ANXaZ5w2y5aOe9dV3tKF4llhlI="} 2.9867196e+07
+# HELP wireguard_peers_count Number of active peers
+# TYPE wireguard_peers_count gauge
+wireguard_peers_count{ifname="wg0"} 1
+# HELP wireguard_rx_bytes Number of received bytes
+# TYPE wireguard_rx_bytes counter
+wireguard_rx_bytes{ifname="wg0",publicKey="5CL0j1HMDxK0ftLz2ANXaZ5w2y5aOe9dV3tKF4llhlI="} 2.9867196e+07
+# HELP wireguard_tx_bytes Number of transferred bytes
+# TYPE wireguard_tx_bytes counter
+wireguard_tx_bytes{ifname="wg0",publicKey="5CL0j1HMDxK0ftLz2ANXaZ5w2y5aOe9dV3tKF4llhlI="} 2.746656e+06
+```
+
+For example this is how you edit your WireGuard configuration file:
+
+```ini
+[Interface]
+Address = 192.168.0.8/24
+PrivateKey = ******uWogB6cn/Mw********j3dZeB54C1SIn4iG2k=
+
+[Peer]
+PublicKey = 5CL0j1HMDxK0ftLz2ANXaZ5w2y5aOe9dV3tKF4llhlI=
+AllowedIPs = 192.168.0.0/24,192.168.1.0/24
+PersistentKeepalive = 5
+Endpoint = wg0.example.com:443
+```
+
+## Flags
+❗SUDO RULES❗️
+If the `wireguard-exporter` is not launched as `root`, then the user must have sudo rights
+```shell
+someuser ALL=(root) NOPASSWD: /usr/bin/wg
+```
+You can simply run the `wireguard-exporter` file with standard settings on any host that has utility `wg`
+
+You can call `wireguard-exporter -h` to print all available flags
+
+```shell
+root@myhost:~# ./wireguard-exporter -h
+Usage of ./wireguard-exporter-linux-amd64:
+  --log.format string
+        Output format of log messages. One of: [text, json] (default "text")
+  --log.level string
+        Only log messages with the given severity or above. One of: [debug, info, warn, error] (default "info")
+  --web.listem.address string
+        Address to listen (default "0.0.0.0:9172")
+```
+
+### Build for another platform
+If your platform is not in the releases, you can build it yourself, for this you only need a Go compiler. Just execute this shell script by changing `GOOS` and `GOARCH` with according [GoLang specification](https://gist.github.com/asukakenji/f15ba7e588ac42795f421b48b8aede63)
+```shell
+GOOS=linux # REQUIRED REPLACE
+GOARCH=amd64 # REQUIRED REPLACE
+
+export GOARCH=$GOARCH
+export GOOS=$GOOS
+file="wireguard-exporter-$GOOS-$GOARCH"
+go build -ldflags "-s -w" -o $file main.go
+```
+If everything went well, just transfer the file `wireguard-exporter-...-...` to your host and execute him
+
+
+### Simple systemd service file
+
+❗SUDO RULES❗️
+If the `wireguard-exporter` is not launched as `root`, then the user must have sudo rights
+```shell
+someuser ALL=(root) NOPASSWD: /usr/bin/wg
+```
+
+Now add the exporter to the Prometheus exporters as usual. I recommend to start it as a service. It's necessary to run it as root or configure a sudo rule (if there is a non-root way to call `wg show all dump` please let me know). My systemd service file is like this one:
+
+```ini
+[Unit]
+Description=Prometheus WireGuard Exporter
+Wants=network-online.target
+After=network-online.target
+
+[Service]
+User=someuser
+Group=someuser
+Type=simple
+ExecStart=/usr/local/bin/wireguard-exporter \
+    --log.format text \
+    --log.level info \
+    --web.listem.address 0.0.0.0:9172
+Restart=on-failure
+RestartSec=15s
+
+[Install]
+WantedBy=multi-user.target
+```
+

go.mod

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+module main
+
+go 1.22.2
+
+require github.com/prometheus/client_golang v1.19.1
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.48.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
+	golang.org/x/sys v0.17.0 // indirect
+	google.golang.org/protobuf v1.33.0 // indirect
+)

go.sum

@@ -0,0 +1,20 @@
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/prometheus/client_golang v1.19.1 h1:wZWJDwK+NameRJuPGDhlnFgx8e8HN3XHQeLaYJFJBOE=
+github.com/prometheus/client_golang v1.19.1/go.mod h1:mP78NwGzrVks5S2H6ab8+ZZGJLZUq1hoULYBAYBw1Ho=
+github.com/prometheus/client_model v0.5.0 h1:VQw1hfvPvk3Uv6Qf29VrPF32JB6rtbgI6cYPYQjL0Qw=
+github.com/prometheus/client_model v0.5.0/go.mod h1:dTiFglRmd66nLR9Pv9f0mZi7B7fk5Pm3gvsjB5tr+kI=
+github.com/prometheus/common v0.48.0 h1:QO8U2CdOzSn1BBsmXJXduaaW+dY/5QLjfB8svtSzKKE=
+github.com/prometheus/common v0.48.0/go.mod h1:0/KsvlIEfPQCQ5I2iNSAWKPZziNCvRs5EC6ILDTlAPc=
+github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k6Bo=
+github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
+golang.org/x/sys v0.17.0 h1:25cE3gD+tdBA7lp7QfhuV+rJiE9YXTcS3VG1SqssI/Y=
+golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
+google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=

main.go

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+package main
+
+import (
+	"flag"
+	"main/src"
+	"net/http"
+	"os"
+)
+
+var (
+	webListenAddress = flag.String("web.listem.address", "0.0.0.0:9172", "Address to listen")
+	logLevel         = flag.String("log.level", "info", "Only log messages with the given severity or above. One of: [debug, info, warn, error]")
+	logFormat        = flag.String("log.format", "text", "Output format of log messages. One of: [text, json]")
+)
+
+func main() {
+	// Parse flags
+	flag.Parse()
+
+	// Init logger
+	src.Init(logLevel, logFormat)
+	logger := src.GetLogger()
+
+	logger.Info("Exporter is started")
+
+	// Start HTTP server
+	server := http.NewServeMux()
+	server.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
+		src.Router(writer, request, logger)
+	})
+	logger.Info("Starting HTTP server on " + *webListenAddress + "")
+	err := http.ListenAndServe(*webListenAddress, server)
+	if err != nil {
+		logger.Error(err.Error())
+		os.Exit(1)
+	}
+}

src/logger.go

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+package src
+
+import (
+	"log/slog"
+	"os"
+)
+
+var (
+	mylogger *slog.Logger
+)
+
+func Init(level *string, format *string) {
+	var l_level slog.Level
+	switch *level {
+	case "debug":
+		l_level = slog.LevelDebug
+	case "warn":
+		l_level = slog.LevelWarn
+	case "error":
+		l_level = slog.LevelError
+	default:
+		l_level = slog.LevelInfo
+	}
+
+	// Select format
+	var handler slog.Handler
+	switch *format {
+	case "json":
+		handler = slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: l_level})
+	default:
+		handler = slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{Level: l_level})
+	}
+	mylogger = slog.New(handler)
+}
+
+func GetLogger() *slog.Logger {
+	return mylogger
+}

src/router.go

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+package src
+
+import (
+	"log/slog"
+	"main/src/routes"
+	"net/http"
+)
+
+// Router routes handler
+func Router(writer http.ResponseWriter, request *http.Request, logger *slog.Logger) {
+	switch request.RequestURI {
+	case "/metrics":
+		routes.Metrics(writer, request, logger)
+	default:
+		routes.NotFound(writer, request, logger)
+	}
+
+}