exit 0 without key on Windows to avoid Winget Validation-Executable-Error (#2376, #2247)

internal/cmd/agent/agent.go

@@ -1,9 +1,11 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"log"
 	"os"
+	"runtime"
 	"strings"
 
 	"github.com/henrygd/beszel"
@@ -14,6 +16,12 @@ import (
 	"golang.org/x/crypto/ssh"
 )
 
+type noKeyProvidedError struct{}
+
+func (noKeyProvidedError) Error() string {
+	return "no key provided: must set -key flag, KEY env var, or KEY_FILE env var. Use 'beszel-agent help' for usage"
+}
+
 // cli options
 type cmdOptions struct {
 	key    string // key is the public key(s) for SSH authentication.
@@ -124,7 +132,7 @@ func (opts *cmdOptions) loadPublicKeys() ([]ssh.PublicKey, error) {
 	// Try key file
 	keyFile, ok := utils.GetEnv("KEY_FILE")
 	if !ok {
-		return nil, fmt.Errorf("no key provided: must set -key flag, KEY env var, or KEY_FILE env var. Use 'beszel-agent help' for usage")
+		return nil, noKeyProvidedError{}
 	}
 
 	pubKey, err := os.ReadFile(keyFile)
@@ -138,6 +146,14 @@ func (opts *cmdOptions) getAddress() string {
 	return agent.GetAddress(opts.listen)
 }
 
+func isBenignStartupError(err error, goos string) bool {
+	if goos != "windows" {
+		return false
+	}
+	var noKeyErr noKeyProvidedError
+	return errors.As(err, &noKeyErr)
+}
+
 // handleFingerprint handles the "fingerprint" command with subcommands "view" and "reset".
 func handleFingerprint() {
 	subCmd := ""
@@ -182,6 +198,12 @@ func main() {
 	var err error
 	serverConfig.Keys, err = opts.loadPublicKeys()
 	if err != nil {
+		if isBenignStartupError(err, runtime.GOOS) {
+			// WinGet launches the executable without configuration during validation.
+			// Exit successfully in that case while retaining the error on other platforms.
+			log.Print("Failed to load public keys:", err)
+			return
+		}
 		log.Fatal("Failed to load public keys:", err)
 	}
 

internal/cmd/agent/agent_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"crypto/ed25519"
+	"errors"
 	"os"
 	"path/filepath"
 	"testing"
@@ -187,6 +188,26 @@ func TestLoadPublicKeys(t *testing.T) {
 	}
 }
 
+func TestIsBenignStartupError(t *testing.T) {
+	tests := []struct {
+		name string
+		err  error
+		goos string
+		want bool
+	}{
+		{name: "missing key on windows", err: noKeyProvidedError{}, goos: "windows", want: true},
+		{name: "wrapped missing key on windows", err: errors.Join(errors.New("startup failed"), noKeyProvidedError{}), goos: "windows", want: true},
+		{name: "missing key on linux", err: noKeyProvidedError{}, goos: "linux", want: false},
+		{name: "different error on windows", err: errors.New("invalid key"), goos: "windows", want: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.want, isBenignStartupError(tt.err, tt.goos))
+		})
+	}
+}
+
 func TestGetNetwork(t *testing.T) {
 	tests := []struct {
 		name     string