feat: authenticate users and agents requests

internal/command/client/flag/flag.go

@@ -2,9 +2,13 @@ package flag
 
 import (
 	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
 
 	"forge.cadoles.com/Cadoles/emissary/internal/format"
 	"forge.cadoles.com/Cadoles/emissary/internal/format/table"
+	"github.com/pkg/errors"
 	"github.com/urfave/cli/v2"
 )
 
@@ -28,6 +32,17 @@ func ComposeFlags(flags ...cli.Flag) []cli.Flag {
 			Usage:   fmt.Sprintf("use `MODE` as output mode (available: %s)", []format.OutputMode{format.OutputModeCompact, format.OutputModeWide}),
 			Value:   string(format.OutputModeCompact),
 		},
+		&cli.StringFlag{
+			Name:    "token",
+			Aliases: []string{"t"},
+			Usage:   "use `TOKEN` as authentification token",
+		},
+		&cli.StringFlag{
+			Name:      "token-file",
+			Usage:     "use `TOKEN_FILE` as file containing the authentification token",
+			Value:     ".emissary-token",
+			TakesFile: true,
+		},
 	}
 
 	flags = append(flags, baseFlags...)
@@ -39,16 +54,43 @@ type BaseFlags struct {
 	ServerURL  string
 	Format     format.Format
 	OutputMode format.OutputMode
+	Token      string
+	TokenFile  string
 }
 
 func GetBaseFlags(ctx *cli.Context) *BaseFlags {
 	serverURL := ctx.String("server")
 	rawFormat := ctx.String("format")
 	rawOutputMode := ctx.String("output-mode")
+	tokenFile := ctx.String("token-file")
+	token := ctx.String("token")
 
 	return &BaseFlags{
 		ServerURL:  serverURL,
 		Format:     format.Format(rawFormat),
 		OutputMode: format.OutputMode(rawOutputMode),
+		Token:      token,
+		TokenFile:  tokenFile,
 	}
 }
+
+func GetToken(flags *BaseFlags) (string, error) {
+	if flags.Token != "" {
+		return flags.Token, nil
+	}
+
+	if flags.TokenFile == "" {
+		return "", nil
+	}
+
+	rawToken, err := ioutil.ReadFile(flags.TokenFile)
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return "", errors.WithStack(err)
+	}
+
+	if rawToken == nil {
+		return "", nil
+	}
+
+	return strings.TrimSpace(string(rawToken)), nil
+}