# @opentelemetry/baggage-span-processor

> OpenTelemetry Baggage Span Processor for Node.js

Latest version **0.5.0** (published 2025-12-17) · Apache-2.0 license · 0 weekly downloads

## Install

```sh
npm install @opentelemetry/baggage-span-processor
pnpm add @opentelemetry/baggage-span-processor
yarn add @opentelemetry/baggage-span-processor
bun add @opentelemetry/baggage-span-processor
```

## Health

**Score 65/100 (B)** — status: stable.

Positive: has types; no vulnerabilities; has provenance; high maintenance score; high quality score.

Warnings: low downloads; no esm support; pre 1.0.

## Facts

| | |
|---|---|
| Version | 0.5.0 |
| Published | 2025-12-17 |
| First published | 2024-05-02 |
| Weekly downloads | 0 |
| License | Apache-2.0 |
| TypeScript types | bundled |
| Module format | CommonJS |
| Node | ^18.19.0 \|\| >=20.6.0 |
| Dependencies | 1 |
| Unpacked size | 31.3 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 927 |
| Author | OpenTelemetry Authors |
| Maintainers | dyladan, pichlermarc |
| Keywords | opentelemetry, nodejs, tracing, baggage, plugin |

## Links

- npm: https://www.npmjs.com/package/@opentelemetry/baggage-span-processor
- Repository: https://github.com/open-telemetry/opentelemetry-js-contrib
- Homepage: https://github.com/open-telemetry/opentelemetry-js-contrib/tree/main/packages/baggage-span-processor#readme
- Issues: https://github.com/open-telemetry/opentelemetry-js-contrib/issues
- npm.io page: https://npm.io/package/@opentelemetry/baggage-span-processor

## Dependencies (1)

- [@opentelemetry/sdk-trace-base](https://npm.io/package/@opentelemetry/sdk-trace-base.md) ^2.0.0

## Recent versions

- 0.5.0 (latest) — 2025-12-17
- 0.4.2 — 2025-09-29
- 0.4.1 — 2025-09-29
- 0.4.0 — 2025-03-18
- 0.3.1 — 2024-06-10
- 0.3.0 — 2024-06-06
- 0.2.0 — 2024-05-15
- 0.1.0 — 2024-05-02

## README

# OpenTelemetry Baggage Span Processor for Node.js

[![NPM Published Version][npm-img]][npm-url]
[![Apache License][license-image]][license-url]

The BaggageSpanProcessor reads entries stored in Baggage from the parent context and adds the [baggage](https://opentelemetry.io/docs/concepts/signals/baggage) entries' keys and
values to the span as attributes on span start.

Add this span processor to a tracer provider.

Keys and values added to Baggage will appear on subsequent child spans for a trace within this service *and* be propagated to external services in accordance with any configured propagation formats configured.
If the external services also have a Baggage span processor, the keys and values will appear in those child spans as well.

⚠ Warning ⚠️

Do not put sensitive information in Baggage.

To repeat: a consequence of adding data to Baggage is that the keys and values will appear in all outgoing HTTP headers from the application.

Compatible with OpenTelemetry JS API and SDK `1.0+`.

## Installation

```bash
npm install --save @opentelemetry/baggage-span-processor
```

### Usage

Add to the span processors that copies all baggage entries during configuration:

```javascript
import { NodeSDK, tracing } from '@opentelemetry/sdk-node';
import { ALLOW_ALL_BAGGAGE_KEYS, BaggageSpanProcessor } from '@opentelemetry/baggage-span-processor';

const spanProcessors = [
  new tracing.SimpleSpanProcessor(
    new tracing.ConsoleSpanExporter()),
  new BaggageSpanProcessor(ALLOW_ALL_BAGGAGE_KEYS)];

const sdk = new NodeSDK({
  serviceName: "example-service",
  spanProcessors
});

sdk.start();
```

Alternatively, you can provide a custom baggage key predicate to select which baggage keys you want to copy.

For example, to only copy baggage entries that start with `my-key`:

```javascript
new BaggageSpanProcessor((baggageKey: string) => key.startsWith('my-key'))
```

For example, to only copy baggage entries that matches the regex `^key.+`:

```javascript
const regex = new RegExp("^key.+")
new BaggageSpanProcessor((baggageKey: string) => regex.test(baggageKey))
```

## Useful links

- For more information on OpenTelemetry, visit: <https://opentelemetry.io/>
- For more about OpenTelemetry JavaScript: <https://github.com/open-telemetry/opentelemetry-js>
- For help or feedback on this project, join us in [GitHub Discussions][discussions-url]

## License

APACHE 2.0 - See [LICENSE][license-url] for more information.

[discussions-url]: https://github.com/open-telemetry/opentelemetry-js/discussions
[license-url]: https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/LICENSE
[license-image]: https://img.shields.io/badge/license-Apache_2.0-green.svg?style=flat
[npm-url]: https://www.npmjs.com/package/@opentelemetry/baggage-span-processor
[npm-img]: https://badge.fury.io/js/%40opentelemetry%2Fbaggage-span-processor.svg

---
_Source: https://npm.io/package/@opentelemetry/baggage-span-processor · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._