apache/beam · error

error encoding bool

Error message

error encoding bool

What it means

EncodeBool writes a single byte (0 or 1) per the Beam runner protocol; this wraps any I/O failure from that write with 'error encoding bool'. It indicates the underlying writer failed mid-serialization, not a type problem. Common underlying causes are broken pipes, closed writers, or disk/network errors when the coder output goes to a stream or file.

Source

Thrown at sdks/go/pkg/beam/core/graph/coder/bool.go:35

import (
	"io"

	"github.com/apache/beam/sdks/v2/go/pkg/beam/core/util/ioutilx"
	"github.com/apache/beam/sdks/v2/go/pkg/beam/internal/errors"
)

// EncodeBool encodes a boolean according to the beam protocol.
func EncodeBool(v bool, w io.Writer) error {
	// Encoding: false = 0, true = 1
	var err error
	if v {
		_, err = ioutilx.WriteUnsafe(w, []byte{1})
	} else {
		_, err = ioutilx.WriteUnsafe(w, []byte{0})
	}
	if err != nil {
		return errors.Wrap(err, "error encoding bool")
	}
	return nil
}

// DecodeBool decodes a boolean according to the beam protocol.
func DecodeBool(r io.Reader) (bool, error) {
	// Encoding: false = 0, true = 1
	var b [1]byte
	if err := ioutilx.ReadNBufUnsafe(r, b[:]); err != nil {
		if err == io.EOF {
			return false, err
		}
		return false, errors.Wrap(err, "error decoding bool")
	}
	switch b[0] {
	case 0:
		return false, nil
	case 1:

View on GitHub (pinned to 12126d8942)

Solutions

1. Inspect the wrapped cause (errors.Unwrap) to find the real I/O failure (broken pipe, closed connection, disk full).
2. Check network/worker health if this occurs during pipeline execution; retry the affected stage.
3. Verify custom sinks keep the writer open for the duration of encoding.
4. Add retry/timeout handling on the transport feeding the io.Writer.

Example fix

// before: writer may be closed before encode finishes
w.Close()
EncodeBool(true, w)
// after: encode first, then close
EncodeBool(true, w)
w.Close()

// Go
if err := coder.EncodeBool(v, w); err != nil {
    cause := errors.Unwrap(err)
    log.Printf("bool encode failed: %v", cause) // inspect real I/O error
    return err
}

When it happens

Trigger: EncodeBool(v, w) when w is closed, broken (pipe), or returns a write error — e.g. during sink serialization to a failed network stream or full disk.

Common situations: Runner shut down while a stage is still encoding elements; network failures streaming encoded records between workers; writing to a closed file or connection in custom sinks.

Related errors

• error encoding bool: %v
• error decoding bool
• error decoding byte
• empty chunk
• No data

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/9ded0a6230980505. Report an issue: GitHub.