fix: Spdy migration to websocket (#6682)

* spdy-migrate to websocket

* spdy-migrate to websocket

* websocket

* refc

Author: prkhrkat

pkg/terminal/fallback_executor.go

@@ -0,0 +1,74 @@
+package terminal
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/url"
+
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+// FallbackExecutor tries WebSocket first and falls back to SPDY if needed
+type FallbackExecutor struct {
+	executor remotecommand.Executor
+}
+
+// NewFallbackExecutor creates a new executor that tries WebSocket first and falls back to SPDY
+func NewFallbackExecutor(config *rest.Config, method string, url *url.URL) (remotecommand.Executor, error) {
+	var wsExecutor, spdyExecutor remotecommand.Executor
+	var wsErr, spdyErr error
+
+	// Try to create WebSocket executor
+	wsExecutor, wsErr = remotecommand.NewWebSocketExecutor(config, method, url.String())
+	if wsErr != nil {
+		log.Printf("Warning: Failed to create WebSocket executor: %v", wsErr)
+	}
+
+	// Try to create SPDY executor
+	spdyExecutor, spdyErr = remotecommand.NewSPDYExecutor(config, method, url)
+	if spdyErr != nil {
+		log.Printf("Warning: Failed to create SPDY executor: %v", spdyErr)
+	}
+
+	// Handle different scenarios
+	if wsErr != nil && spdyErr != nil {
+		// Both failed
+		return nil, fmt.Errorf("failed to create any executor: WebSocket error: %v, SPDY error: %v", wsErr, spdyErr)
+	}
+
+	if wsErr != nil {
+		// Only WebSocket failed, use SPDY
+		return spdyExecutor, nil
+	}
+
+	if spdyErr != nil {
+		// Only SPDY failed, use WebSocket
+		return wsExecutor, nil
+	}
+
+	// Both succeeded, create fallback executor
+	fallbackExecutor, err := remotecommand.NewFallbackExecutor(wsExecutor, spdyExecutor, func(err error) bool {
+		// Fall back to SPDY if WebSocket fails due to connection issues
+		log.Printf("WebSocket failed, falling back to SPDY: %v", err)
+		return true
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to create fallback executor: %v", err)
+	}
+
+	return &FallbackExecutor{
+		executor: fallbackExecutor,
+	}, nil
+}
+
+// Stream is deprecated. Please use StreamWithContext.
+func (e *FallbackExecutor) Stream(options remotecommand.StreamOptions) error {
+	return e.executor.Stream(options)
+}
+
+// StreamWithContext delegates to the underlying fallback executor
+func (e *FallbackExecutor) StreamWithContext(ctx context.Context, options remotecommand.StreamOptions) error {
+	return e.executor.StreamWithContext(ctx, options)
+}

pkg/terminal/terminalSesion.go

@@ -24,7 +24,6 @@ import (
 	"encoding/json"
 	errors2 "errors"
 	"fmt"
-	"github.com/devtron-labs/common-lib/async"
 	"io"
 	"log"
 	"net/http"
@@ -33,6 +32,8 @@ import (
 	"sync"
 	"time"
 
+	"github.com/devtron-labs/common-lib/async"
+
 	"github.com/caarlos0/env"
 	"github.com/devtron-labs/common-lib/utils/k8s"
 	"github.com/devtron-labs/devtron/internal/middleware"
@@ -358,7 +359,8 @@ func getExecutor(k8sClient kubernetes.Interface, cfg *rest.Config, podName, name
 		TTY:       tty,
 	}, scheme.ParameterCodec)
 
-	exec, err := remotecommand.NewSPDYExecutor(cfg, "POST", req.URL())
+	// Use the new fallback executor instead of SPDY directly
+	exec, err := NewFallbackExecutor(cfg, "POST", req.URL())
 	return exec, err
 }
 

pkg/terminal/websocket_executor.go

@@ -0,0 +1,37 @@
+package terminal
+
+import (
+	"context"
+	"net/url"
+
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+// WebSocketExecutor wraps the Kubernetes WebSocket executor
+type WebSocketExecutor struct {
+	executor remotecommand.Executor
+}
+
+// NewWebSocketExecutor creates a new WebSocket-based executor for terminal sessions
+func NewWebSocketExecutor(config *rest.Config, method string, url *url.URL) (remotecommand.Executor, error) {
+	// Use the Kubernetes WebSocket executor directly
+	executor, err := remotecommand.NewWebSocketExecutor(config, method, url.String())
+	if err != nil {
+		return nil, err
+	}
+
+	return &WebSocketExecutor{
+		executor: executor,
+	}, nil
+}
+
+// Stream is deprecated. Please use StreamWithContext.
+func (e *WebSocketExecutor) Stream(options remotecommand.StreamOptions) error {
+	return e.executor.Stream(options)
+}
+
+// StreamWithContext delegates to the underlying Kubernetes WebSocket executor
+func (e *WebSocketExecutor) StreamWithContext(ctx context.Context, options remotecommand.StreamOptions) error {
+	return e.executor.StreamWithContext(ctx, options)
+}