Cloudflare Workers Types
:stop_sign: This repository was for @cloudflare/workers-types versions ≤ 3 and is no longer maintained.
Since version 4, types are automatically generated from and in the workerd repository.
Find the new README here and the new auto-generation scripts here.
Please raise issues with type definitions in the workerd repository, tagging @cloudflare/workers-types in your report.
Legacy Documentation
## Install
```bash
npm install -D @cloudflare/workers-types
-- Or
yarn add -D @cloudflare/workers-types
```
## Usage
> :warning: If you're upgrading from version 2, make sure to remove `webworker` from the `lib` array in your
> `tsconfig.json`. These types are now included in `@cloudflare/workers-types`.
The following is a minimal `tsconfig.json` for use alongside this package:
**`tsconfig.json`**
```json
{
"compilerOptions": {
"target": "ES2020",
"module": "CommonJS",
"lib": ["ES2020"],
"types": ["@cloudflare/workers-types"]
}
}
```
### Using bindings
It's recommended that you create an ambient type file for any bindings your Worker uses. Create a file named
`bindings.d.ts` in your src directory:
**`bindings.d.ts`**
```typescript
export {};
declare global {
const MY_ENV_VAR: string;
const MY_SECRET: string;
const myKVNamespace: KVNamespace;
}
```
## Auto-Generation
Types are automatically generated from the Workers runtime's source code on every release. However, these generated
types don't include any generics or overloads, so to improve ergonomics, some of them are overridden.
The [`overrides`](./overrides) directory contains partial TypeScript declarations. If an override has a different type
classification than its generated counterpart – for example, an `interface` is declared to override a generated `class`
definition – then the override is used instead of the generated output. However, if they're the same type classification
(e.g. both the override and the generated output are using `class`), then their member properties are merged:
- Members in the override but not in the generated type are included in the output
- If a member in the override has the same name as one in the generated type, the generated one is removed from the
output, and the override is included instead
- If the member is declared type `never` in the override, it is removed from the output
If a named type override is declared as a type alias to `never`, that named type is removed from the output.
JSDoc comments from overrides will also be copied over to the output.
Comment overrides can also be written in Markdown. The [`docs`](./docs) directory contains these overrides.
2nd level headings are the names of top level declarations (e.g. ## \`KVNamespace\`),
3rd level headings are for member names (e.g. ### \`KVNamespace#put\`), and 4th level
headings correspond to JSDoc sections for members:
- `#### Parameters`: a list with parameters of the form - \`param\`: param description, these will be
formatted as `@param` tags
- `#### Returns`: contents will be copied as-is to the `@returns` tag
- `#### Examples`: fenced code blocks with the language set to `js`, `ts`, `javascript` or `typescript` will be copied
to `@example` tags