feat(nest): add retry logic for 429 and 409 errors with exponential backoff

pkg/nest/api.go

@@ -166,6 +166,11 @@ func (a *API) ExchangeSDP(projectID, deviceID, offer string) (string, error) {
 
 	uri := "https://smartdevicemanagement.googleapis.com/v1/enterprises/" +
 		projectID + "/devices/" + deviceID + ":executeCommand"
+
+	maxRetries := 3
+	retryDelay := time.Second * 30
+
+	for attempt := 0; attempt < maxRetries; attempt++ {
 		req, err := http.NewRequest("POST", uri, bytes.NewReader(b))
 		if err != nil {
 			return "", err
@@ -178,6 +183,27 @@ func (a *API) ExchangeSDP(projectID, deviceID, offer string) (string, error) {
 		if err != nil {
 			return "", err
 		}
+
+		// Handle 409 (Conflict) and 429 (Too Many Requests)
+		if res.StatusCode == 409 || res.StatusCode == 429 {
+			res.Body.Close()
+			if attempt < maxRetries-1 {
+				log.Info().
+					Int("status", res.StatusCode).
+					Float64("delay", retryDelay.Seconds()).
+					Int("attempt", attempt+1).
+					Int("max_retries", maxRetries-1).
+					Msg("API request failed, retrying")
+				// Get new token from Google
+				if err := a.refreshToken(); err != nil {
+					return "", err
+				}
+				time.Sleep(retryDelay)
+				retryDelay *= 2 // exponential backoff
+				continue
+			}
+		}
+
 		defer res.Body.Close()
 
 		if res.StatusCode != 200 {
@@ -204,6 +230,44 @@ func (a *API) ExchangeSDP(projectID, deviceID, offer string) (string, error) {
 		return resv.Results.Answer, nil
 	}
 
+	return "", errors.New("nest: max retries exceeded")
+}
+
+func (a *API) refreshToken() error {
+	// Get the cached API with matching token to get credentials
+	var refreshKey string
+	cacheMu.Lock()
+	for key, api := range cache {
+		if api.Token == a.Token {
+			refreshKey = key
+			break
+		}
+	}
+	cacheMu.Unlock()
+
+	if refreshKey == "" {
+		return errors.New("nest: unable to find cached credentials")
+	}
+
+	// Parse credentials from cache key
+	parts := strings.Split(refreshKey, ":")
+	if len(parts) != 3 {
+		return errors.New("nest: invalid cache key format")
+	}
+	clientID, clientSecret, refreshToken := parts[0], parts[1], parts[2]
+
+	// Get new API instance which will refresh the token
+	newAPI, err := NewAPI(clientID, clientSecret, refreshToken)
+	if err != nil {
+		return err
+	}
+
+	// Update current API with new token
+	a.Token = newAPI.Token
+	a.ExpiresAt = newAPI.ExpiresAt
+	return nil
+}
+
 func (a *API) ExtendStream() error {
 	var reqv struct {
 		Command string `json:"command"`

pkg/nest/client.go

@@ -4,13 +4,17 @@ import (
 	"errors"
 	"net/url"
 	"strings"
+	"time"
 
+	"github.com/AlexxIT/go2rtc/internal/app"
 	"github.com/AlexxIT/go2rtc/pkg/core"
 	"github.com/AlexxIT/go2rtc/pkg/rtsp"
 	"github.com/AlexxIT/go2rtc/pkg/webrtc"
 	pion "github.com/pion/webrtc/v3"
 )
 
+var log = app.GetLogger("nest")
+
 type WebRTCClient struct {
 	conn *webrtc.Conn
 	api  *API
@@ -38,9 +42,32 @@ func Dial(rawURL string) (core.Producer, error) {
 		return nil, errors.New("nest: wrong query")
 	}
 
-	nestAPI, err := NewAPI(cliendID, cliendSecret, refreshToken)
-	if err != nil {
-		return nil, err
+	maxRetries := 3
+	retryDelay := time.Second * 30
+
+	var nestAPI *API
+	var lastErr error
+
+	for attempt := 0; attempt < maxRetries; attempt++ {
+		nestAPI, err = NewAPI(cliendID, cliendSecret, refreshToken)
+		if err == nil {
+			break
+		}
+		lastErr = err
+		if attempt < maxRetries-1 {
+			log.Info().
+				Float64("delay", retryDelay.Seconds()).
+				Int("attempt", attempt+1).
+				Int("max_retries", maxRetries-1).
+				Err(err).
+				Msg("API initialization failed, retrying")
+			time.Sleep(retryDelay)
+			retryDelay *= 2 // exponential backoff
+		}
+	}
+
+	if nestAPI == nil {
+		return nil, lastErr
 	}
 
 	protocols := strings.Split(query.Get("protocols"), ",")
@@ -79,6 +106,11 @@ func (c *WebRTCClient) MarshalJSON() ([]byte, error) {
 }
 
 func rtcConn(nestAPI *API, rawURL, projectID, deviceID string) (*WebRTCClient, error) {
+	maxRetries := 3
+	retryDelay := time.Second * 30
+	var lastErr error
+
+	for attempt := 0; attempt < maxRetries; attempt++ {
 		rtcAPI, err := webrtc.NewAPI()
 		if err != nil {
 			return nil, err
@@ -112,6 +144,18 @@ func rtcConn(nestAPI *API, rawURL, projectID, deviceID string) (*WebRTCClient, e
 		// 4. Exchange SDP via Hass
 		answer, err := nestAPI.ExchangeSDP(projectID, deviceID, offer)
 		if err != nil {
+			lastErr = err
+			if attempt < maxRetries-1 {
+				log.Info().
+					Float64("delay", retryDelay.Seconds()).
+					Int("attempt", attempt+1).
+					Int("max_retries", maxRetries-1).
+					Err(err).
+					Msg("WebRTC connection setup failed, retrying")
+				time.Sleep(retryDelay)
+				retryDelay *= 2
+				continue
+			}
 			return nil, err
 		}
 
@@ -123,6 +167,9 @@ func rtcConn(nestAPI *API, rawURL, projectID, deviceID string) (*WebRTCClient, e
 		return &WebRTCClient{conn: conn, api: nestAPI}, nil
 	}
 
+	return nil, lastErr
+}
+
 func rtspConn(nestAPI *API, rawURL, projectID, deviceID string) (*RTSPClient, error) {
 	rtspURL, err := nestAPI.GenerateRtspStream(projectID, deviceID)
 	if err != nil {