http-boot-config/config/main.go

package main

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"io/fs"
	"os"

	"git.faercol.me/faercol/http-boot-config/config/logger"
	"git.faercol.me/faercol/http-boot-config/config/prober"
	"git.faercol.me/faercol/http-boot-config/config/remote"
	"github.com/google/uuid"
)

type action int

const (
	actionList action = iota
	actionGetRemote
	actionUnknown
)

type cliArgs struct {
	debug       bool
	colour      bool
	action      action
	id          uuid.UUID
	remoteAddr  string
	prettyPrint bool
}

var defaultArgs cliArgs = cliArgs{
	debug:  false,
	colour: true,
	action: actionUnknown,
}

func parseArgs() (cliArgs, error) {
	args := defaultArgs
	var firstArg int

	listFlagSet := flag.NewFlagSet("list", flag.ExitOnError)

	getRemoteFlagSet := flag.NewFlagSet("get-remote", flag.ExitOnError)
	uuidFlag := getRemoteFlagSet.String("uuid", "", "Client UUID")
	remoteFlag := getRemoteFlagSet.String("remote-host", "http://localhost:5000", "Address for the remote boot server")
	jsonFlag := getRemoteFlagSet.Bool("json", false, "Display the result in JSON format")

	debugFlag := flag.Bool("debug", false, "Display debug logs")
	noColourFlag := flag.Bool("no-colour", false, "Disable colour logs")

	for i, v := range os.Args {
		switch v {
		case "list":
			args.action = actionList
		case "get-remote":
			args.action = actionGetRemote
		default:
			continue
		}
		firstArg = i + 1
	}

	switch args.action {
	case actionList:
		listFlagSet.Parse(os.Args[firstArg:])
	case actionGetRemote:
		getRemoteFlagSet.Parse(os.Args[firstArg:])
		parsedID, err := uuid.Parse(*uuidFlag)
		if err != nil {
			return args, fmt.Errorf("invalid format for uuid %q", *uuidFlag)
		}
		args.id = parsedID
		args.remoteAddr = *remoteFlag
		args.prettyPrint = !*jsonFlag
	default:
		flag.Parse()
		return cliArgs{}, errors.New("missing an action")
	}

	flag.Parse()
	args.debug = *debugFlag
	args.colour = !*noColourFlag
	return args, nil
}

func displayAppList(l *logger.SimpleLogger) {
	l.Info("Checking EFI directory for available boot images...")
	apps, err := prober.GetEFIApps(l)
	if err != nil {
		if errors.Is(err, fs.ErrPermission) {
			l.Fatal("Permission error, try to run the command as sudo")
		}
		l.Fatalf("Failed to check EFI directory: %s", err.Error())
	}

	l.Info("Found the following EFI applications:")
	for _, a := range apps {
		prefix := " "
		if a.Active {
			prefix = "*"
		}
		l.Infof("\t- %s[%d] %s: %s", prefix, a.ID, a.Name, a.Path)
	}
}

func getRemoteConfig(l *logger.SimpleLogger, host string, id uuid.UUID, pretty bool) {
	l.Info("Getting config from remote server...")
	if pretty {
		if err := remote.DisplayRemoteConfigPretty(context.Background(), host, id, l); err != nil {
			l.Fatal(err.Error())
		}
	} else {
		if err := remote.DisplayRemoteConfigJSON(context.Background(), host, id, l); err != nil {
			l.Fatal(err.Error())
		}
	}
}

func main() {
	args, err := parseArgs()
	if err != nil {
		l := logger.New(true, false)
		l.Fatalf("Invalid command: %s", err.Error())
	}
	l := logger.New(args.colour, args.debug)
	fmt.Print("")

	switch args.action {
	case actionList:
		displayAppList(l)
	case actionGetRemote:
		getRemoteConfig(l, args.remoteAddr, args.id, args.prettyPrint)
	default:
		l.Fatal("Unknown action")
	}
}