Fail fast when bundle and discovery plugins faced with unrecoverable errors.

Signed-off-by: Pushpalanka Jayawardhana <[email protected]>

Author: Pushpalanka

filters/openpolicyagent/openpolicyagent.go

@@ -481,61 +481,78 @@ func (registry *OpenPolicyAgentRegistry) new(store storage.Store, configBytes []
 // Start asynchronously starts the policy engine's plugins that download
 // policies, report status, etc.
 func (opa *OpenPolicyAgentInstance) Start(ctx context.Context, timeout time.Duration) error {
+
 	discoveryPlugin := discovery.Lookup(opa.manager)
-	bundlePlugin := bundle.Lookup(opa.manager)
 
 	done := make(chan struct{})
-	defer close(done)
-	failed := make(chan error)
-	defer close(failed)
+	failed := make(chan error, 1)
 
-	discoveryPlugin.RegisterListener("startuplistener", func(status bundle.Status) {
-		if len(status.Errors) > 0 {
-			failed <- fmt.Errorf("discovery download failed: %w", errors.Join(status.Errors...))
-		}
+	var registerDiscoveryListenerOnce sync.Once
+	registerDiscoveryListenerOnce.Do(func() {
+		discoveryPlugin.RegisterListener("skipper-instance-startup-discovery", func(status bundle.Status) {
+			handleStatusErrors(status, failed, "discovery plugin")
+		})
 	})
-
-	bundlePlugin.Register("startuplistener", func(status bundle.Status) {
-		if len(status.Errors) > 0 {
-			failed <- fmt.Errorf("bundle activation failed: %w", errors.Join(status.Errors...))
+	defer discoveryPlugin.Unregister("skipper-instance-startup-discovery")
+
+	// Register listener for "bundle" status
+	var registerBundleListenerOnce sync.Once
+	opa.manager.RegisterPluginStatusListener("skipper-instance-startup-plugin", func(status map[string]*plugins.Status) {
+		if _, exists := status["bundle"]; exists {
+			bundlePlugin := bundle.Lookup(opa.manager)
+			if bundlePlugin != nil {
+				registerBundleListenerOnce.Do(func() {
+					bundlePlugin.Register("skipper-instance-startup-bundle", func(status bundle.Status) {
+						handleStatusErrors(status, failed, "bundle plugin")
+					})
+				})
+				defer bundlePlugin.Unregister("skipper-instance-startup-bundle")
+			}
 		}
 	})
-	defer bundlePlugin.Unregister("startuplistener")
+	defer opa.manager.UnregisterPluginStatusListener("skipper-instance-startup-plugin")
 
-	opa.manager.RegisterPluginStatusListener("startuplistener", func(status map[string]*plugins.Status) {
-		for _, pluginstatus := range status {
-			if pluginstatus != nil && pluginstatus.State != plugins.StateOK {
+	// Register listener for general plugin status checks
+	opa.manager.RegisterPluginStatusListener("generalStartUpListener", func(status map[string]*plugins.Status) {
+		for _, pluginStatus := range status {
+			if pluginStatus != nil && pluginStatus.State != plugins.StateOK {
 				return
 			}
 		}
 		close(done)
 	})
-	defer opa.manager.UnregisterPluginStatusListener("startuplistener")
+	defer opa.manager.UnregisterPluginStatusListener("generalStartUpListener")
 
 	err := opa.manager.Start(ctx)
 	if err != nil {
 		return err
 	}
 
 	select {
-	case <-done:
-		return nil
-	case err := <-failed:
-		opa.Close(ctx)
-
-		return err
 	case <-ctx.Done():
+		timeoutErr := ctx.Err()
+
 		for pluginName, status := range opa.manager.PluginStatus() {
 			if status != nil && status.State != plugins.StateOK {
 				opa.Logger().WithFields(map[string]interface{}{
 					"plugin_name":   pluginName,
 					"plugin_state":  status.State,
 					"error_message": status.Message,
-				}).Error("Open policy agent plugin did not start in time")
+				}).Error("Open policy agent plugin: %v did not start in time", pluginName)
 			}
 		}
 		opa.Close(ctx)
-		return fmt.Errorf("one or more open policy agent plugins failed to start in %v with error: %w", timeout, err)
+		if timeoutErr != nil {
+			return fmt.Errorf("one or more open policy agent plugins failed to start in %v with error: %w", timeout, timeoutErr)
+		}
+		return fmt.Errorf("one or more open policy agent plugins failed to start in %v", timeout)
+
+	case <-done:
+		return nil
+	case err := <-failed:
+		opa.Close(ctx)
+
+		return err
 	}
 }
 
@@ -546,25 +563,6 @@ func (opa *OpenPolicyAgentInstance) Close(ctx context.Context) {
 	})
 }
 
-func waitFunc(ctx context.Context, fun func() bool, interval time.Duration) error {
-	if fun() {
-		return nil
-	}
-	ticker := time.NewTicker(interval)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-ctx.Done():
-			return fmt.Errorf("timed out while starting: %w", ctx.Err())
-		case <-ticker.C:
-			if fun() {
-				return nil
-			}
-		}
-	}
-}
-
 func configLabelsInfo(opaConfig config.Config) func(*plugins.Manager) {
 	info := ast.NewObject()
 	labels := ast.NewObject()
@@ -821,3 +819,46 @@ func (l *QuietLogger) Error(fmt string, a ...interface{}) {
 func (l *QuietLogger) Warn(fmt string, a ...interface{}) {
 	l.target.Warn(fmt, a)
 }
+
+var temporaryClientErrorHTTPCodes = map[int64]struct{}{
+	429: {}, // too many requests
+	408: {}, // request timeout
+}
+
+func isTemporaryError(code int64) bool {
+	_, exists := temporaryClientErrorHTTPCodes[code]
+	return exists
+}
+
+func handleStatusErrors(
+	status bundle.Status,
+	failed chan error,
+	prefix string,
+) {
+	if status.Code == "bundle_error" {
+		if status.HTTPCode == "" {
+			failed <- formatStatusError(prefix, status)
+			return
+		}
+		code, err := status.HTTPCode.Int64()
+		if err == nil {
+			if code >= 400 && code < 500 && !isTemporaryError(code) {
+				// Fail for error codes in the range 400-500 excluding temporary errors
+				failed <- formatStatusError(prefix, status)
+				return
+			} else if code >= 500 {
+				// Do not fail for 5xx errors and keep retrying
+				return
+			}
+		}
+		if err != nil {
+			failed <- formatStatusError(prefix, status)
+			return
+		}
+	}
+}
+
+func formatStatusError(prefix string, status bundle.Status) error {
+	return fmt.Errorf("%s failed: Name: %s, Code: %s, Message: %s, HTTPCode: %s, Errors: %v",
+		prefix, status.Name, status.Code, status.Message, status.HTTPCode, status.Errors)
+}