http-echo/main.go at master · queueb-org/http-echo · GitHub

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package main

import (
	"fmt"
	"log/slog"
	"os"
	"runtime"

	"github.com/spf13/cobra"

	alog "common.queueb.org/alog"

	"queueb.org/http-echo/cmd/app"
	"queueb.org/http-echo/cmd/common"
	"queueb.org/http-echo/pkg"
)

const (
	appName = "http-echo"
	//: env variables

	//: exit codes
	exitOk           = 0
	exitCommandError = 2
)

var (
	appVersion = pkg.Version()

	logger *alog.Logger

	// Exit function
	Exit = func(code int) {
		os.Exit(code)
	}

	rootCmd = &cobra.Command{
		Use:     appName,
		Short:   "a simple web application",
		Example: "httpecho server",
	}
	versionCmd = &cobra.Command{
		Use:     "version",
		Aliases: []string{"ver", "V"},
		Example: "version",
		Run: func(cmd *cobra.Command, args []string) {
			version := fmt.Sprintf(
				"%[1]s version: %[2]s, %[3]s/%[4]s %[5]s",
				appName, appVersion, runtime.GOOS, runtime.GOARCH, runtime.Version())
			fmt.Println(version)
		},
	}
)

func exit(err error) {
	if err == nil {
		Exit(exitOk)
		// this return makes sense only for testing, due to
		// there's no real system exit from this function, thus far
		// running in tests it will continue to follow the code sequence.
		return
	}
	Exit(exitCommandError)
}

func init() {
	//: processing flags
	rootCmd.PersistentFlags().AddFlagSet(common.GlobalFlags)

	//: registering local commands
	rootCmd.AddCommand(versionCmd)
	rootCmd.AddCommand(app.NewCommands()...)
}

func appInfo(logLevel slog.Level) []any {
	return []any{
		slog.Group("http-echo",
			slog.String("version", appVersion),
			slog.String("log-level", alog.LogLevelString(logLevel)),
		),
		slog.Group("golang",
			slog.String("version", runtime.Version()),
			slog.String("arch", runtime.GOARCH),
		),
	}
}

func main() {
	alog.SetEnv(common.AppEnv)
	logLevel := alog.ParseVerbosity()
	logger = alog.New(slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{
		AddSource:   false, // if true it works, but in the scope of main only.
		Level:       logLevel,
		ReplaceAttr: alog.DefaultReplaceAttr,
	}))
	alog.ReplaceDefault(logger)
	alog.Default().Trace("started", appInfo(logLevel)...)

	//: registering local commands
	rootCmd.AddGroup(
		&cobra.Group{ID: common.CobraGroupMain, Title: "Main:"},
		&cobra.Group{ID: common.CobraGroupAux, Title: "Aux:"},
	)
	err := rootCmd.Execute()
	exit(err)
}