fix(http): ignore normal EOF when decoding HTTP response blocks

conn_http.go

@@ -443,6 +443,10 @@ func (h *httpConnect) readData(reader *chproto.Reader, timezone *time.Location,
 
 	// Try to decode the block
 	if err := block.Decode(reader, h.revision); err != nil {
+		if errors.Is(err, io.EOF) && (captureBuffer == nil || !bytes.Contains(captureBuffer.Bytes(), []byte("__exception__"))) {
+			return nil, io.EOF
+		}
+
 		// Decode failed - check if captured data contains exception marker
 		// The decode error typically happens because it tries to read the
 		// "__exception__" marker as binary data
@@ -461,7 +465,7 @@ func (h *httpConnect) readData(reader *chproto.Reader, timezone *time.Location,
 		if len(remaining) > 0 && captureBuffer != nil {
 			captureBuffer.Write(remaining)
 		}
-		if readErr != nil {
+		if readErr != nil && !errors.Is(readErr, io.EOF) {
 			h.logger.Error("HTTP read data: decode error while parsing exception block", slog.Any("error", err))
 		}
 

conn_http_exception_test.go

@@ -5,6 +5,8 @@ import (
 	"errors"
 	"strings"
 	"testing"
+
+	chproto "github.com/ClickHouse/ch-go/proto"
 )
 
 func TestParseExceptionFromBytes(t *testing.T) {
@@ -287,3 +289,22 @@ func TestCapturingReader(t *testing.T) {
 		})
 	}
 }
+
+func TestHTTPReadDataEOFDoesNotLogDecodeError(t *testing.T) {
+	var logBuf bytes.Buffer
+	h := &httpConnect{
+		logger: slog.New(slog.NewTextHandler(&logBuf, &slog.HandlerOptions{Level: slog.LevelDebug})),
+	}
+
+	reader := chproto.NewReader(bytes.NewReader(nil))
+	block, err := h.readData(reader, nil, &bytes.Buffer{})
+	if !errors.Is(err, io.EOF) {
+		t.Fatalf("expected io.EOF, got %v", err)
+	}
+	if block != nil {
+		t.Fatalf("expected nil block, got %#v", block)
+	}
+	if got := logBuf.String(); got != "" {
+		t.Fatalf("expected no error log, got %q", got)
+	}
+}