emissary/internal/command/main.go

package command

import (
	"context"
	"fmt"
	"os"
	"sort"
	"time"

	"github.com/pkg/errors"
	"github.com/urfave/cli/v2"

	// Spec validation
	_ "forge.cadoles.com/Cadoles/emissary/internal/spec/proxy"
	_ "forge.cadoles.com/Cadoles/emissary/internal/spec/uci"
)

func Main(buildDate, projectVersion, gitRef, defaultConfigPath string, commands ...*cli.Command) {
	ctx := context.Background()

	compiled, err := time.Parse(time.RFC3339, buildDate)
	if err != nil {
		panic(errors.Wrapf(err, "could not parse build date '%s'", buildDate))
	}

	app := &cli.App{
		Version:  fmt.Sprintf("%s (%s, %s)", projectVersion, gitRef, buildDate),
		Compiled: compiled,
		Name:     "emissary",
		Usage:    "Control plane for edge devices",
		Commands: commands,
		Before: func(ctx *cli.Context) error {
			workdir := ctx.String("workdir")
			// Switch to new working directory if defined
			if workdir != "" {
				if err := os.Chdir(workdir); err != nil {
					return errors.Wrap(err, "could not change working directory")
				}
			}

			if err := ctx.Set("projectVersion", projectVersion); err != nil {
				return errors.WithStack(err)
			}

			if err := ctx.Set("gitRef", gitRef); err != nil {
				return errors.WithStack(err)
			}

			if err := ctx.Set("buildDate", buildDate); err != nil {
				return errors.WithStack(err)
			}

			return nil
		},
		Flags: []cli.Flag{
			&cli.StringFlag{
				Name:  "workdir",
				Value: "",
				Usage: "The working directory",
			},
			&cli.StringFlag{
				Name:   "projectVersion",
				Value:  "",
				Hidden: true,
			},
			&cli.StringFlag{
				Name:   "gitRef",
				Value:  "",
				Hidden: true,
			},
			&cli.StringFlag{
				Name:   "buildDate",
				Value:  "",
				Hidden: true,
			},
			&cli.BoolFlag{
				Name:    "debug",
				EnvVars: []string{"EMISSARY_DEBUG"},
				Value:   false,
			},
			&cli.StringFlag{
				Name:      "config",
				Aliases:   []string{"c"},
				EnvVars:   []string{"EMISSARY_CONFIG"},
				Value:     defaultConfigPath,
				TakesFile: true,
			},
		},
	}

	app.ExitErrHandler = func(ctx *cli.Context, err error) {
		if err == nil {
			return
		}

		debug := ctx.Bool("debug")

		if !debug {
			fmt.Printf("[ERROR] %v\n", err)
		} else {
			fmt.Printf("%+v", err)
		}
	}

	sort.Sort(cli.FlagsByName(app.Flags))
	sort.Sort(cli.CommandsByName(app.Commands))

	if err := app.RunContext(ctx, os.Args); err != nil {
		os.Exit(1)
	}
}