WS client constructor

Author: alpe

apps/evm/cmd/run.go

@@ -60,7 +60,7 @@ var RunCmd = &cobra.Command{
 			return err
 		}
 
-		blobClient, err := blobrpc.NewClient(context.Background(), nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+		blobClient, err := blobrpc.NewWSClient(context.Background(), 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.NewClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	blobClient, err := blobrpc.NewWSClient(ctx, 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.NewClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	blobClient, err := blobrpc.NewWSClient(ctx, 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

@@ -107,14 +107,8 @@ func StartNode(
 		}()
 	}
 
-	blobClient, err := blobrpc.NewClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
-	if err != nil {
-		return fmt.Errorf("failed to create blob client: %w", err)
-	}
-	defer blobClient.Close()
-	daClient := block.NewDAClient(blobClient, nodeConfig, logger)
-
-	// create a new remote signer
+	// Validate and load signer first (before attempting DA connection, which may fail
+	// eagerly over WebSocket if no DA server is running).
 	var signer signer.Signer
 	if nodeConfig.Signer.SignerType == "file" && (nodeConfig.Node.Aggregator && !nodeConfig.Node.BasedSequencer) {
 		// Get passphrase file path
@@ -152,6 +146,13 @@ func StartNode(
 		return fmt.Errorf("unknown signer type: %s", nodeConfig.Signer.SignerType)
 	}
 
+	blobClient, err := blobrpc.NewWSClient(ctx, nodeConfig.DA.Address, nodeConfig.DA.AuthToken, "")
+	if err != nil {
+		return fmt.Errorf("failed to create blob client: %w", err)
+	}
+	defer blobClient.Close()
+	daClient := block.NewDAClient(blobClient, nodeConfig, logger)
+
 	// sanity check for based sequencer
 	if nodeConfig.Node.BasedSequencer && genesis.DAStartHeight == 0 {
 		return fmt.Errorf("based sequencing requires DAStartHeight to be set in genesis. This value should be identical for all nodes of the chain")

pkg/da/jsonrpc/client.go

@@ -25,15 +25,16 @@ func (c *Client) Close() {
 }
 
 // httpToWS converts an HTTP(S) URL to a WebSocket URL.
-// go-jsonrpc requires WebSocket for channel-based subscriptions (e.g. Subscribe).
-// WebSocket connections also support regular RPC calls, so this is backward-compatible.
 func httpToWS(addr string) string {
 	addr = strings.Replace(addr, "https://", "wss://", 1)
 	addr = strings.Replace(addr, "http://", "ws://", 1)
 	return addr
 }
 
-// NewClient connects to the celestia-node RPC endpoint
+// NewClient connects to the DA RPC endpoint using the address as-is.
+// Uses HTTP by default (lazy connection — only connects on first RPC call).
+// Does NOT support channel-based subscriptions (e.g. Subscribe).
+// For subscription support, use NewWSClient instead.
 func NewClient(ctx context.Context, addr, token string, authHeaderName string) (*Client, error) {
 	var httpHeader http.Header
 	if token != "" {
@@ -43,19 +44,16 @@ func NewClient(ctx context.Context, addr, token string, authHeaderName string) (
 		httpHeader = http.Header{authHeaderName: []string{fmt.Sprintf("Bearer %s", token)}}
 	}
 
-	// Use WebSocket so that channel-based subscriptions (blob.Subscribe) work.
-	wsAddr := httpToWS(addr)
-
 	var cl Client
 
 	// Connect to the blob namespace
-	blobCloser, err := jsonrpc.NewClient(ctx, wsAddr, "blob", &cl.Blob.Internal, httpHeader)
+	blobCloser, err := jsonrpc.NewClient(ctx, addr, "blob", &cl.Blob.Internal, httpHeader)
 	if err != nil {
 		return nil, fmt.Errorf("failed to connect to blob namespace: %w", err)
 	}
 
 	// Connect to the header namespace
-	headerCloser, err := jsonrpc.NewClient(ctx, wsAddr, "header", &cl.Header.Internal, httpHeader)
+	headerCloser, err := jsonrpc.NewClient(ctx, addr, "header", &cl.Header.Internal, httpHeader)
 	if err != nil {
 		blobCloser()
 		return nil, fmt.Errorf("failed to connect to header namespace: %w", err)
@@ -70,6 +68,15 @@ func NewClient(ctx context.Context, addr, token string, authHeaderName string) (
 	return &cl, nil
 }
 
+// NewWSClient connects to the DA RPC endpoint over WebSocket.
+// 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)
+}
+
 // BlobAPI mirrors celestia-node's blob module (nodebuilder/blob/blob.go).
 // jsonrpc.NewClient wires Internal.* to RPC stubs.
 type BlobAPI struct {