dc-polyfill

dc-polyfill: Diagnostics Channel Polyfill

This package provides a polyfill (or ponyfill) for the diagnostics_channel core Node.js module (including TracingChannel) for use with older versions of Node.js. It aims to remain simple, with zero dependencies, and only taking up a few kilobytes of space.

dc-polyfill attempts to backport every feature and bugfix that is added to Node.js core. If a feature hasn't been backported then please open a Pull Request or open an issue.

Currently this package provides an API compatible with diagnostics_channel as of Node.js v20.6. Therefore, to view the capabilities of this package, read the Node.js diagnostics_channel documentation.

Whenever the currently running version of Node.js ships with diagnostics_channel, dc-polyfill will make sure to use the global registry of channels provided by the core module. However, for old versions of Node.js which lack it, dc-polyfill instead uses a global symbol to track the channels. This symbol will remain the same for all versions of dc-polyfill to avoid the issue where multiple versions of an npm library installed in a dependency hierarchy usually provide different singletons.

Ideally, this package will forever remain backwards compatible, and there will never be a v2.x release.

Usage

npm install dc-polyfill

const diagnostics_channel = require('dc-polyfill');

Contributing

When a Pull Request is created the code runs against many different versions of Node.js. Notably, versions right before a change and versions right after a change, the first version of a release line, and the last version of a release line.

Currently this module tests Node.js >= v12.17. If you would like to use dc-polyfill for versions of Node.js older than this then feel free to submit a Pull Request or open an issue.

License / Copyright

See LICENSE.txt for full details.

MIT License - Copyright (c) 2023 Datadog, Inc.