Add listen address and version flag

Add new command line flags:
-listen-address=":9103"
-version

Also fix container build date to be the actual build date.

.goreleaser.yaml

@@ -4,6 +4,8 @@ before:
 builds:
   - env:
       - CGO_ENABLED=0
+    ldflags:
+      - -s -w -X "main.Version=v{{ .Version }}" -X "main.GitCommit={{ .FullCommit }}"
     goos:
       - linux
       - windows
@@ -30,7 +32,7 @@ dockers:
       - --label=org.opencontainers.image.url=https://github.com/jayme-github/{{ .ProjectName }}
       - --label=org.opencontainers.image.source=https://github.com/jayme-github/{{ .ProjectName }}
       - --label=org.opencontainers.image.version=v{{ .Version }}
-      - --label=org.opencontainers.image.created={{ time "2006-01-02T15:04:05Z07:00" }}
+      - --label=org.opencontainers.image.created={{ .Date }}
       - --label=org.opencontainers.image.revision={{ .FullCommit }}
       - --label=org.opencontainers.image.licenses=GPLv3
   - image_templates: ["jaymedh/{{ .ProjectName }}:v{{ .Version }}-arm64v8"]
@@ -46,7 +48,7 @@ dockers:
       - --label=org.opencontainers.image.url=https://github.com/jayme-github/{{ .ProjectName }}
       - --label=org.opencontainers.image.source=https://github.com/jayme-github/{{ .ProjectName }}
       - --label=org.opencontainers.image.version=v{{ .Version }}
-      - --label=org.opencontainers.image.created={{ time "2006-01-02T15:04:05Z07:00" }}
+      - --label=org.opencontainers.image.created={{ .Date }}
       - --label=org.opencontainers.image.revision={{ .FullCommit }}
       - --label=org.opencontainers.image.licenses=GPLv3
 docker_manifests:

go.sum

@@ -62,8 +62,6 @@ github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0/go.mod h1:8NvIoxWQoOIhqOTXgf
 github.com/grpc-ecosystem/grpc-gateway v1.9.0/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
-github.com/jayme-github/fritzctl v1.4.23-0.20220206160018-2185c66d7f6f h1:0Hw74rytK5dUZJKHw5hiQX5V8NSl+uXZOTsIqO/joL8=
-github.com/jayme-github/fritzctl v1.4.23-0.20220206160018-2185c66d7f6f/go.mod h1:8bJv/qlxE0sdIAwjSLyuc+NeQ4kz77bMCdCCZOKJQjc=
 github.com/jayme-github/fritzctl v1.4.23-0.20220424111445-826538a7c038 h1:QhPu2bo814Kss65tEu6s30PBbkAueJb8wNCkwa/JD9M=
 github.com/jayme-github/fritzctl v1.4.23-0.20220424111445-826538a7c038/go.mod h1:8bJv/qlxE0sdIAwjSLyuc+NeQ4kz77bMCdCCZOKJQjc=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=

main.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"net/url"
 	"os"
+	"runtime"
 	"sync"
 	"time"
 
@@ -44,6 +45,9 @@ func NewClient(options ...fritz.Option) *client {
 }
 
 var (
+	Version         = "development"
+	GitCommit       = ""
+	GoVersion       = runtime.Version()
 	fritzClient     *client
 	fbURL           *url.URL
 	username        = flag.String("username", "", "FRITZ!Box username.")
@@ -52,11 +56,12 @@ var (
 	noVerify        = flag.Bool("noverify", false, "Omit TLS verification of the FRITZ!Box certificate.")
 	certificatePath = flag.String("cert", "", "Path to the FRITZ!Box certificate.")
 	loglevel        = flag.String("loglevel", "warn", "Logging verbosity (debug, info, warn, error or none)")
+	listenAddress   = flag.String("listen-address", ":9103", "Address on which to expose metrics")
+	version         = flag.Bool("version", false, "Print version number and exit")
 )
 
 func validateFlags() {
 	var err error
-	flag.Parse()
 
 	l := &fritzctllogger.Level{}
 	if err := l.Set(*loglevel); err != nil {
@@ -95,6 +100,13 @@ func validateFlags() {
 }
 
 func main() {
+	flag.Parse()
+
+	if *version {
+		fmt.Printf("Version: \"%s\", GitCommit: \"%s\", GoVersion: \"%s\"\n", Version, GitCommit, GoVersion)
+		return
+	}
+
 	validateFlags()
 
 	options := []fritz.Option{
@@ -135,7 +147,7 @@ func main() {
 	prometheus.MustRegister(fc)
 	http.Handle("/metrics", promhttp.Handler())
 
-	if err := http.ListenAndServe(":9103", nil); err != nil {
+	if err := http.ListenAndServe(*listenAddress, nil); err != nil {
 		log.Fatalln(err)
 	}
 }