improve request logic and simplify protocol error handling logic

examples/unlock/unlock.go

@@ -32,7 +32,7 @@ func main() {
 
 	// Specify the user-agent header value used in HTTP requests to Tesla's servers. The default
 	// value is constructed from your package name and account.LibraryVersion.
-	account.UserAgent = "example-unlock/1.0.0"
+	userAgent := "example-unlock/1.0.0"
 
 	if vin == "" {
 		logger.Printf("Must specify VIN")
@@ -61,7 +61,7 @@ func main() {
 
 	// This example program sends commands over the Internet, which requires a Tesla account login
 	// token. The protocol can also work over BLE; see other programs in the example directory.
-	acct, err := account.New(string(oauthToken))
+	acct, err := account.New(string(oauthToken), userAgent)
 	if err != nil {
 		logger.Printf("Authentication error: %s", err)
 		return

pkg/account/account.go

@@ -24,13 +24,9 @@ import (
 var (
 	//go:embed version.txt
 	libraryVersion string
-	// UserAgent is sent in HTTP requests.
-	//
-	// The default value is "<main package name>/<commit hash> tesla-sdk/<version>".
-	UserAgent = buildUserAgent()
 )
 
-func buildUserAgent() string {
+func buildUserAgent(app string) string {
 	library := strings.TrimSpace("tesla-sdk/" + libraryVersion)
 	build, ok := debug.ReadBuildInfo()
 	if !ok {
@@ -40,26 +36,29 @@ func buildUserAgent() string {
 	if len(path) == 0 {
 		return library
 	}
-	app := path[len(path)-1]
-
-	var version string
-	if build.Main.Version != "(devel)" && build.Main.Version != "" {
-		version = build.Main.Version
-	} else {
-		for _, info := range build.Settings {
-			if info.Key == "vcs.revision" {
-				if len(info.Value) > 8 {
-					version = info.Value[0:8]
+
+	if app == "" {
+		app = path[len(path)-1]
+		var version string
+		if build.Main.Version != "(devel)" && build.Main.Version != "" {
+			version = build.Main.Version
+		} else {
+			for _, info := range build.Settings {
+				if info.Key == "vcs.revision" {
+					if len(info.Value) > 8 {
+						version = info.Value[0:8]
+					}
+					break
 				}
-				break
 			}
 		}
-	}
 
-	if version == "" {
-		return fmt.Sprintf("%s %s", app, library)
+		if version != "" {
+			app = fmt.Sprintf("%s/%s", app, version)
+		}
 	}
-	return fmt.Sprintf("%s/%s %s", app, version, library)
+
+	return fmt.Sprintf("%s %s", app, library)
 }
 
 // Account allows interaction with a Tesla account.
@@ -114,7 +113,8 @@ func (p *oauthPayload) domain() string {
 }
 
 // New returns an [Account] that can be used to fetch a [vehicle.Vehicle].
-func New(oauthToken string) (*Account, error) {
+// Optional userAgent can be passed in - otherwise it will be generated from code
+func New(oauthToken, userAgent string) (*Account, error) {
 	parts := strings.Split(oauthToken, ".")
 	if len(parts) != 3 {
 		return nil, fmt.Errorf("client provided malformed OAuth token")
@@ -133,7 +133,7 @@ func New(oauthToken string) (*Account, error) {
 		return nil, fmt.Errorf("client provided OAuth token with invalid audiences")
 	}
 	return &Account{
-		UserAgent:  UserAgent,
+		UserAgent:  buildUserAgent(userAgent),
 		authHeader: "Bearer " + strings.TrimSpace(oauthToken),
 		Host:       domain,
 	}, nil

pkg/account/account_test.go

@@ -13,29 +13,29 @@ func b64Encode(payload string) string {
 
 func TestNewAccount(t *testing.T) {
 	validDomain := "fleet-api.example.tesla.com"
-	if _, err := New(""); err == nil {
+	if _, err := New("", ""); err == nil {
 		t.Error("Returned success empty JWT")
 	}
-	if _, err := New(b64Encode(validDomain)); err == nil {
+	if _, err := New(b64Encode(validDomain), ""); err == nil {
 		t.Error("Returned success on one-field JWT")
 	}
-	if _, err := New("x." + b64Encode(validDomain)); err == nil {
+	if _, err := New("x."+b64Encode(validDomain), ""); err == nil {
 		t.Error("Returned success on two-field JWT")
 	}
-	if _, err := New("x." + b64Encode(validDomain) + "y.z"); err == nil {
+	if _, err := New("x."+b64Encode(validDomain)+"y.z", ""); err == nil {
 		t.Error("Returned success on four-field JWT")
 	}
-	if _, err := New("x." + validDomain + ".y"); err == nil {
+	if _, err := New("x."+validDomain+".y", ""); err == nil {
 		t.Error("Returned success on non-base64 encoded JWT")
 	}
-	if _, err := New("x." + b64Encode("{\"aud\": \"example.com\"}") + ".y"); err == nil {
+	if _, err := New("x."+b64Encode("{\"aud\": \"example.com\"}")+".y", ""); err == nil {
 		t.Error("Returned success on untrusted domain")
 	}
-	if _, err := New("x." + b64Encode(fmt.Sprintf("{\"aud\": \"%s\"}", validDomain)) + ".y"); err == nil {
+	if _, err := New("x."+b64Encode(fmt.Sprintf("{\"aud\": \"%s\"}", validDomain))+".y", ""); err == nil {
 		t.Error("Returned when aud field not a list")
 	}
 
-	acct, err := New("x." + b64Encode(fmt.Sprintf("{\"aud\": [\"%s\"]}", validDomain)) + ".y")
+	acct, err := New("x."+b64Encode(fmt.Sprintf("{\"aud\": [\"%s\"]}", validDomain))+".y", "")
 	if err != nil {
 		t.Fatalf("Returned error on valid JWT: %s", err)
 	}
@@ -49,7 +49,7 @@ func TestDomainDefault(t *testing.T) {
 		Audiences: []string{"https://auth.tesla.com/nts"},
 	}
 
-	acct, err := New(makeTestJWT(payload))
+	acct, err := New(makeTestJWT(payload), "")
 	if err != nil {
 		t.Fatalf("Returned error on valid JWT: %s", err)
 	}
@@ -64,7 +64,7 @@ func TestDomainExtraction(t *testing.T) {
 		OUCode:    "EU",
 	}
 
-	acct, err := New(makeTestJWT(payload))
+	acct, err := New(makeTestJWT(payload), "")
 	if err != nil {
 		t.Fatalf("Returned error on valid JWT: %s", err)
 	}

pkg/cli/config.go

@@ -421,7 +421,7 @@ func (c *Config) Account() (*account.Account, error) {
 	if err != nil {
 		return nil, err
 	}
-	return account.New(token)
+	return account.New(token, "")
 }
 
 // SavePrivateKey writes skey to the system keyring or file, depending on what options are

pkg/connector/inet/inet.go

@@ -119,10 +119,8 @@ func SendFleetAPICommand(ctx context.Context, client *http.Client, userAgent, au
 	switch result.StatusCode {
 	case http.StatusOK:
 		return body, nil
-	case http.StatusUnprocessableEntity:
-		if bytes.Contains(body, []byte("vehicle does not support signed commands")) {
-			return nil, protocol.ErrProtocolNotSupported
-		}
+	case http.StatusUnprocessableEntity: // HTTP: 422 on commands endpoint means protocol is not supported (fallback to regular commands)
+		return nil, protocol.ErrProtocolNotSupported
 	case http.StatusServiceUnavailable:
 		return nil, ErrVehicleNotAwake
 	case http.StatusRequestTimeout: