gomonop/main.go

package main

import (
	"fmt"
	"os"
	"path/filepath"

	"nocternity.net/gomonop/cmd/sslcert"
	"nocternity.net/gomonop/cmd/zoneserial"
	"nocternity.net/gomonop/pkg/program"
	"nocternity.net/gomonop/pkg/version"
)

var (
	programs map[string]program.ProgramBuilder = map[string]program.ProgramBuilder{
		"check_ssl_certificate": sslcert.NewProgram,
		"check_zone_serial":     zoneserial.NewProgram,
	}
)

func exitError(msg string, args ...interface{}) {
	fmt.Fprintf(os.Stderr, msg+"\n", args...)
	os.Exit(1)
}

func main() {
	ownName := filepath.Base(os.Args[0])

	var program program.Program
	if builder, ok := programs[ownName]; ok {
		program = builder()
	} else if len(os.Args) < 2 {
		exitError(
			""+
				"Syntax: %s <program> [arguments]\n"+
				"        %s --programs|-p\n"+
				"        %s --version|-v",
			os.Args[0], os.Args[0], os.Args[0])
	} else if os.Args[1] == "--programs" || os.Args[1] == "-p" {
		for name := range programs {
			fmt.Println(name)
		}
		os.Exit(0)
	} else if os.Args[1] == "--version" || os.Args[1] == "-v" {
		fmt.Printf("gomonop %s\n", version.Version())
		os.Exit(0)

	} else if builder, ok := programs[os.Args[1]]; ok {
		os.Args = os.Args[1:]
		program = builder()
	} else {
		exitError("Unknown program: %s", os.Args[1])
	}

	defer program.Done()
	if program.CheckArguments() {
		program.RunCheck()
	}
}