Get started with command line interface

cmd/presence/check.go

@@ -0,0 +1,9 @@
+package main
+
+type (
+	Check struct{}
+)
+
+func (c *Check) Run(cli *CLI) error {
+	return nil
+}

cmd/presence/detect.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"context"
+
+	"goa.design/clue/log"
+
+	"douglasthrift.net/presence"
+)
+
+type (
+	Detect struct {
+		Interface     string   `arg:""`
+		HardwareAddrs []string `arg:""`
+	}
+)
+
+func (d *Detect) Run(cli *CLI) error {
+	ifs := presence.Interfaces{d.Interface: true}
+	hws := make(presence.HardwareAddrStates, len(d.HardwareAddrs))
+	for _, hw := range d.HardwareAddrs {
+		hws[hw] = presence.NewState()
+	}
+
+	ctx := log.Context(context.Background(), log.WithDisableBuffering(func(context.Context) bool { return true }))
+	a, err := presence.NewARP(1)
+	if err != nil {
+		return err
+	}
+
+	ok, err := a.Present(ctx, ifs, hws)
+	if err != nil {
+		return err
+	}
+	log.Info(ctx, log.KV{K: "present", V: ok})
+	for hw, state := range hws {
+		log.Info(ctx, log.KV{K: "hw", V: hw}, log.KV{K: "present", V: state.Present()}, log.KV{K: "changed", V: state.Changed()})
+	}
+	return nil
+}

cmd/presence/main.go

@@ -1,32 +1,36 @@
 package main
 
 import (
-	"context"
-	"log"
-	"os"
+	"fmt"
+	"runtime"
 
-	"douglasthrift.net/presence"
+	"github.com/alecthomas/kong"
 )
 
-func main() {
-	ifs := presence.Interfaces{os.Args[1]: true}
-	hws := make(presence.HardwareAddrStates, len(os.Args[2:]))
-	for _, hw := range os.Args[2:] {
-		hws[hw] = presence.NewState()
-	}
+type (
+	CLI struct {
+		Version kong.VersionFlag `help:"Show version information." short:"v"`
 
-	ctx := context.Background()
-	a, err := presence.NewARP(1)
-	if err != nil {
-		log.Fatal(err)
+		Detect Detect `cmd:"" help:"Detect network presence and push state changes to IFTTT."`
+		Check  Check  `cmd:"" help:"Check configuration."`
 	}
+)
 
-	ok, err := a.Present(ctx, ifs, hws)
-	if err != nil {
-		log.Fatal(err)
-	}
-	log.Printf("present=%v", ok)
-	for hw, state := range hws {
-		log.Printf("%v present=%v changed=%v", hw, state.Present(), state.Changed())
-	}
+var (
+	version = "dev"
+	commit  = "none"
+	date    = "unknown"
+)
+
+func main() {
+	cli := &CLI{}
+	ctx := kong.Parse(
+		cli,
+		kong.Description("Home network presence detection daemon for IFTTT"), kong.UsageOnError(),
+		kong.Vars{
+			"version": fmt.Sprintf("presence version %v %v %v/%v %v %v", version, runtime.Version(), runtime.GOOS, runtime.GOARCH, commit, date),
+		},
+	)
+	err := ctx.Run(cli)
+	ctx.FatalIfErrorf(err)
 }

go.mod

@@ -2,10 +2,30 @@ module douglasthrift.net/presence
 
 go 1.17
 
-require github.com/stretchr/testify v1.7.2
+require (
+	github.com/alecthomas/kong v0.6.1
+	github.com/stretchr/testify v1.7.5
+	goa.design/clue v0.7.0
+)
 
 require (
-	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-logfmt/logfmt v0.5.1 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/go-cmp v0.5.8 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.opentelemetry.io/otel v1.7.0 // indirect
+	go.opentelemetry.io/otel/trace v1.7.0 // indirect
+	goa.design/goa/v3 v3.7.5 // indirect
+	golang.org/x/net v0.0.0-20220531201128-c960675eff93 // indirect
+	golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a // indirect
+	golang.org/x/term v0.0.0-20220526004731-065cf7ba2467 // indirect
+	golang.org/x/text v0.3.7 // indirect
+	google.golang.org/genproto v0.0.0-20220531173845-685668d2de03 // indirect
+	google.golang.org/grpc v1.47.0 // indirect
+	google.golang.org/protobuf v1.28.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )