fix(pkg/da): fallback to polling when ws cannot connect (#3211)

* fix(pkg/da): fallback to polling when ws cannot connect

* log err and fix typos

* rewording

Author: julienrbrt

apps/evm/cmd/run.go

@@ -59,7 +59,7 @@ var RunCmd = &cobra.Command{
 			return err
 		}
 
-		blobClient, err := blobrpc.NewWSClient(cmd.Context(), nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+		blobClient, err := blobrpc.NewWSClient(cmd.Context(), logger, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
 		if err != nil {
 			return fmt.Errorf("failed to create blob client: %w", err)
 		}

apps/grpc/cmd/run.go

@@ -108,7 +108,7 @@ func createSequencer(
 	genesis genesis.Genesis,
 	executor execution.Executor,
 ) (coresequencer.Sequencer, error) {
-	blobClient, err := blobrpc.NewWSClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	blobClient, err := blobrpc.NewWSClient(ctx, logger, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
 	if err != nil {
 		return nil, fmt.Errorf("failed to create blob client: %w", err)
 	}

apps/testapp/cmd/run.go

@@ -111,7 +111,7 @@ func createSequencer(
 	genesis genesis.Genesis,
 	executor execution.Executor,
 ) (coresequencer.Sequencer, error) {
-	blobClient, err := blobrpc.NewWSClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	blobClient, err := blobrpc.NewWSClient(ctx, logger, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
 	if err != nil {
 		return nil, fmt.Errorf("failed to create blob client: %w", err)
 	}

pkg/cmd/run_node.go

@@ -149,7 +149,7 @@ func StartNode(
 		}
 	}
 
-	blobClient, err := blobrpc.NewWSClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	blobClient, err := blobrpc.NewWSClient(ctx, logger, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
 	if err != nil {
 		return fmt.Errorf("failed to create blob client: %w", err)
 	}

pkg/da/jsonrpc/client.go

@@ -8,6 +8,7 @@ import (
 
 	libshare "github.com/celestiaorg/go-square/v3/share"
 	"github.com/filecoin-project/go-jsonrpc"
+	"github.com/rs/zerolog"
 )
 
 // Client dials the celestia-node RPC "blob" and "header" namespaces.
@@ -72,9 +73,15 @@ func NewClient(ctx context.Context, addr, token string, authHeaderName string) (
 // Automatically converts http:// to ws:// (and https:// to wss://).
 // Supports channel-based subscriptions (e.g. Subscribe).
 // Note: WebSocket connections are eager — they connect at creation time
-// and will fail immediately if the server is unavailable.
-func NewWSClient(ctx context.Context, addr, token string, authHeaderName string) (*Client, error) {
-	return NewClient(ctx, httpToWS(addr), token, authHeaderName)
+// if the initial WS dial fails, falls back to HTTP polling for the entire session.
+func NewWSClient(ctx context.Context, logger zerolog.Logger, addr, token string, authHeaderName string) (*Client, error) {
+	client, err := NewClient(ctx, httpToWS(addr), token, authHeaderName)
+	if err != nil {
+		logger.Warn().Err(err).Msg("DA websocket connection failed, falling back to DA polling")
+		return NewClient(ctx, addr, token, authHeaderName)
+	}
+
+	return client, nil
 }
 
 // BlobAPI mirrors celestia-node's blob module (nodebuilder/blob/blob.go).