denoland-deno/cli/js/web/README.md

# Deno Web APIs

This directory facilities Web APIs that are available in Deno.

Please note, that some of implementations might not be completely aligned with
specification.

Some of the Web APIs are using ops under the hood, eg. `console`, `performance`.

## Implemented Web APIs

- [Blob](https://developer.mozilla.org/en-US/docs/Web/API/Blob): for
  representing opaque binary data
- [Console](https://developer.mozilla.org/en-US/docs/Web/API/Console): for
  logging purposes
- [CustomEvent](https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent),
  [EventTarget](https://developer.mozilla.org/en-US/docs/Web/API/EventTarget)
  and
  [EventListener](https://developer.mozilla.org/en-US/docs/Web/API/EventListener):
  to work with DOM events
  - **Implementation notes:** There is no DOM hierarchy in Deno, so there is no
    tree for Events to bubble/capture through.
- [URL](https://developer.mozilla.org/en-US/docs/Web/API/URL) and
  [URLSearchParams](https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams):
  to construct and parse URLSs
- [fetch](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/fetch),
  [Request](https://developer.mozilla.org/en-US/docs/Web/API/Request),
  [Response](https://developer.mozilla.org/en-US/docs/Web/API/Response),
  [Body](https://developer.mozilla.org/en-US/docs/Web/API/Body) and
  [Headers](https://developer.mozilla.org/en-US/docs/Web/API/Headers): modern
  Promise-based HTTP Request API
- [FormData](https://developer.mozilla.org/en-US/docs/Web/API/FormData): access
  to a `multipart/form-data` serialization
- [Location](https://developer.mozilla.org/en-US/docs/Web/API/Location): parsing
  the current script's URL
  - **Implementation notes:** the `globalThis.location` object cannot be
    manipulated using `assign()`, `reload()` and `replace()` methods. They are
    not implemented.
- [Performance](https://developer.mozilla.org/en-US/docs/Web/API/Performance):
  retrieving current time with a high precision
- [setTimeout](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setTimeout),
  [setInterval](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval),
  [clearTimeout](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/clearTimeout):
  scheduling callbacks in future and
  [clearInterval](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/clearInterval)
- [Worker](https://developer.mozilla.org/en-US/docs/Web/API/Worker): executing
  additional code in a separate thread
  - **Implementation notes:** Blob URLs are not supported, object ownership
    cannot be transferred, posted data is serialized to JSON instead of
    [structured cloning](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm).