### Install WebContainer API with npm

Source: https://webcontainers.io/guides/quickstart

Installs the WebContainer API package using npm. This is the first step to integrate the API into your project.

```bash
npm i @webcontainer/api
```

--------------------------------

### Run npm Install and Dev Server in WebContainer

Source: https://webcontainers.io/guides/quickstart

Shows how to execute commands within the WebContainer, specifically 'npm install' followed by 'npm run dev'. It includes error handling for the install process.

```javascript
async function startDevServer() {
  const installProcess = await webcontainerInstance.spawn('npm', ['install']);

  const installExitCode = await installProcess.exit;

  if (installExitCode !== 0) {
    throw new Error('Unable to run npm install');
  }

  // `npm run dev`
  await webcontainerInstance.spawn('npm', ['run', 'dev']);
}
```

--------------------------------

### Create a WebContainer Instance

Source: https://webcontainers.io/guides/quickstart

Demonstrates how to create a WebContainer instance by importing `WebContainer` and calling the `boot` method. This method should only be called once.

```javascript
import { WebContainer } from '@webcontainer/api';

// Call only once
const webcontainerInstance = await WebContainer.boot();
```

--------------------------------

### Mount Project Files into WebContainer

Source: https://webcontainers.io/guides/quickstart

Loads project files into the WebContainer's file system using the `mount` method. This is recommended for optimal performance, especially on page load.

```javascript
await webcontainerInstance.mount(projectFiles);
```

--------------------------------

### mkdir - Create Directory

Source: https://webcontainers.io/guides/working-with-the-file-system

Creates a new directory at the specified path. Supports creating nested directories recursively.

```APIDOC
## POST /fs/mkdir

### Description
Creates a directory at the specified path. If the directory already exists, an error will be thrown unless the `recursive` option is used.

### Method
POST

### Endpoint
`/fs/mkdir`

### Parameters
#### Query Parameters
- **path** (string) - Required - The path for the new directory.
- **options** (object) - Optional - Options for directory creation.
  - **recursive** (boolean) - Optional - If true, creates parent directories as needed. Defaults to false.

### Request Example
```js
// Create a single directory
await webcontainerInstance.fs.mkdir('src');

// Create nested directories
await webcontainerInstance.fs.mkdir('this/is/my/nested/folder', { recursive: true });
```

### Response
#### Success Response (200)
Indicates the directory was created successfully. No content is typically returned.
```

--------------------------------

### Spawning a Process in WebContainers

Source: https://webcontainers.io/guides/running-processes

Demonstrates how to spawn a process using the `spawn` method in WebContainers. This method takes the command and an array of arguments. It's used here to execute `npm install`.

```javascript
webcontainerInstance.spawn('npm', ['install']);
```

--------------------------------

### Handle Server Ready Event for Preview

Source: https://webcontainers.io/guides/quickstart

Attaches an event listener to the `server-ready` event emitted by the WebContainer. This event provides the URL to preview the application, typically by setting an iframe's source.

```javascript
webcontainerInstance.on('server-ready', (port, url) => (iframeEl.src = url));
```

--------------------------------

### Running a Development Server in WebContainers

Source: https://webcontainers.io/guides/running-processes

An asynchronous function that starts a development server within a WebContainer using `npm run start`. It listens for the `server-ready` event to know when the server is available and provides the port and URL.

```javascript
async function startDevServer() {
  // Run `npm run start` to start the Express app
  await webcontainerInstance.spawn('npm', ['run', 'start']);

  // Wait for `server-ready` event
  webcontainerInstance.on('server-ready', (port, url) => {
    // ...
  });
}
```

--------------------------------

### List Directory Contents in WebContainers

Source: https://webcontainers.io/guides/working-with-the-file-system

Provides an example of how to list the files and directories within a specified directory in the WebContainer's file system using `webcontainerInstance.fs.readdir`. The method returns an array of strings representing the names of the entries in the directory.

```javascript
const files = await webcontainerInstance.fs.readdir('/src');
//    ^ is an array of strings
```

--------------------------------

### Spawning a Process with Multiple Arguments in WebContainers

Source: https://webcontainers.io/guides/running-processes

Illustrates spawning a process with multiple arguments using `webcontainerInstance.spawn`. This example shows how to execute the `ls` command with the `src` directory and the `-l` flag.

```javascript
webcontainerInstance.spawn('ls', ['src', '-l']);
```

--------------------------------

### Configure Cross-Origin Isolation Headers

Source: https://webcontainers.io/guides/quickstart

Specifies the necessary COOP and COEP headers required for WebContainers, which depend on `SharedArrayBuffer`. These headers ensure the website is cross-origin isolated.

```yaml
Cross-Origin-Embedder-Policy: require-corp
Cross-Origin-Opener-Policy: same-origin
```

--------------------------------

### Generating and Mounting Snapshots

Source: https://webcontainers.io/guides/working-with-the-file-system

Explains how to generate a binary snapshot of a local folder using `@webcontainer/snapshot` and how to serve it. It also details how to fetch this snapshot on the client-side and mount it into a WebContainer.

```APIDOC
## Generating and Mounting Snapshots

### Description
Generates a binary snapshot of a folder for efficient mounting in WebContainers. Provides server-side examples (Express, SvelteKit) for serving the snapshot and client-side code for fetching and mounting it.

### Method
`snapshot(source: string): Promise<Buffer>` (from `@webcontainer/snapshot`)
`webcontainerInstance.mount(snapshot: ArrayBuffer)`

### Parameters

#### `snapshot` Function Parameters
- **source** (`string`) - Required - The path to the source code folder on the server.

#### `mount` Method Parameters
- **snapshot** (`ArrayBuffer`) - Required - The binary snapshot data to mount.

### Server-Side Request Example (Express.js)
```javascript
import { snapshot } from '@webcontainer/snapshot';

const SOURCE_CODE_FOLDER = './path/to/your/source-code';
const folderSnapshot = await snapshot(SOURCE_CODE_FOLDER);

app.get('/snapshot', (req, res) => {
  res
    .setHeader('content-type', 'application/octet-stream')
    .send(folderSnapshot);
});
```

### Server-Side Request Example (SvelteKit)
```typescript
import { snapshot } from '@webcontainer/snapshot';

const SOURCE_CODE_FOLDER = './path/to/your/source-code';
const sourceSnapshot = await snapshot(SOURCE_CODE_FOLDER);

export function getSnapshot(req: Request) {
  return new Response(sourceSnapshot, {
    headers: {
      'content-type': 'application/octet-stream',
    },
  });
}
```

### Client-Side Request Example
```javascript
import { WebContainer } from '@webcontainer/api';

const webcontainer = await WebContainer.boot();

const snapshotResponse = await fetch('/snapshot');
const snapshot = await snapshotResponse.arrayBuffer();

await webcontainer.mount(snapshot);
```
```

--------------------------------

### Installing Dependencies in WebContainers

Source: https://webcontainers.io/guides/running-processes

An asynchronous function that installs project dependencies within a WebContainer instance using `npm install`. It returns the exit code of the installation process, indicating success or failure.

```javascript
async function installDependencies() {
  // Install dependencies
  const installProcess = await webcontainerInstance.spawn('npm', ['install']);
  // Wait for install command to exit
  return installProcess.exit;
}
```

--------------------------------

### Configure Specific Page Headers in SvelteKit (hooks.server.js)

Source: https://webcontainers.io/guides/configuring-headers

This SvelteKit example shows how to apply Cross-Origin Isolation headers to a specific page (e.g., '/tutorial') using the `hooks.server.js` file. It checks the request path and conditionally adds the headers, allowing for granular control over security policies.

```javascript
export const handle = async ({ request, resolve }) => {
  const response = await resolve(request);

  if (request.path === '/tutorial') {
    response.headers.set('Cross-Origin-Embedder-Policy', 'require-corp');
    response.headers.set('Cross-Origin-Opener-Policy', 'same-origin');
  }

  return response;
};
```

--------------------------------

### Write File with Encoding (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Writes file content to a specified path using a given encoding. This allows for writing data in different character sets or formats. The example shows writing a string with 'latin1' encoding.

```javascript
await webcontainerInstance.fs.writeFile(
  '/src/main.js',
  '\xE5\x8D\x83\xE8\x91\x89\xE5\xB8\x82\xE3\x83\x96\xE3\x83\xAB\xE3\x83\xBC\xE3\x82\xB9',
  { encoding: 'latin1' }
);
```

```javascript
await webcontainerInstance.fs.writeFile(
  '/src/main.js',
  '\xE5\x8D\x83\xE8\x91\x89\xE5\xB8\x82\xE3\x83\x96\xE3\x83\xAB\xE3\x83\xBC\xE3\x82\xB9',
  { encoding: 'latin1' }
);
```

--------------------------------

### Mounting Files to a Different Path

Source: https://webcontainers.io/guides/working-with-the-file-system

Demonstrates how to mount a file system tree to a specific directory within the WebContainer, rather than the root. It also shows how to create the target directory beforehand if it doesn't exist.

```APIDOC
## Mounting Files to a Different Path

### Description
Mounts a `FileSystemTree` to a specified `mountPoint`. Ensures the directory exists before mounting.

### Method
`webcontainerInstance.mount(files: FileSystemTree, { mountPoint?: string })
webcontainerInstance.fs.mkdir(path: string)

### Parameters

#### `mount` Method Parameters
- **files** (`FileSystemTree`) - Required - The file system tree to mount.
- **mountPoint** (`string`) - Optional - The path within the WebContainer to mount the files. Defaults to root.

#### `mkdir` Method Parameters
- **path** (`string`) - Required - The path of the directory to create.

### Request Example (Mounting with mountPoint)
```javascript
/** @type {import('@webcontainer/api').FileSystemTree} */
const files = {
  'package.json': { content: '{ "name": "my-app" }' },
  'index.html': { content: '<h1>Hello</h1>' },
};

await webcontainerInstance.mount(files, { mountPoint: 'my-mount-point' });
```

### Request Example (Creating directory and mounting)
```javascript
await webcontainerInstance.fs.mkdir('my-mount-point');
await webcontainerInstance.mount(files, { mountPoint: 'my-mount-point' });
```
```

--------------------------------

### writeFile - Write to a File

Source: https://webcontainers.io/guides/working-with-the-file-system

Writes content to a file at the specified path. Creates the file if it doesn't exist or overwrites it if it does. Encoding can also be specified.

```APIDOC
## PUT /fs/writeFile

### Description
Writes data to a file at the specified path. If the file does not exist, it will be created. If it exists, it will be overwritten. An optional encoding can be provided.

### Method
PUT

### Endpoint
`/fs/writeFile`

### Parameters
#### Query Parameters
- **path** (string) - Required - The path where the file will be written.
- **data** (string | Buffer | UInt8Array) - Required - The content to write to the file.
- **options** (object) - Optional - Options for writing the file.
  - **encoding** (string) - Optional - The encoding to use when writing the file. Defaults to 'utf8'.

### Request Example
```js
// Write a string to a file
await webcontainerInstance.fs.writeFile('/src/main.js', 'console.log("Hello from WebContainers!")');

// Write with a specific encoding
await webcontainerInstance.fs.writeFile(
  '/src/main.js',
  '\xE5\x8D\x83\xE8\x91\x89\xE5\xB8\x82\xE3\x83\x96\xE3\x83\xAB\xE3\x83\xBC\xE3\x82\xB9',
  { encoding: 'latin1' }
);
```

### Response
#### Success Response (200)
Indicates the file was written successfully. No content is typically returned.
```

--------------------------------

### Mounting Folders and Files in WebContainer JS

Source: https://webcontainers.io/guides/working-with-the-file-system

Illustrates how to mount directories and their contents within a WebContainer. Directories are represented by a `directory` key, and files within them are nested similarly. This allows for complex project structures to be loaded.

```javascript
/** @type {import('@webcontainer/api').FileSystemTree} */

const files = {
  // This is a directory - provide its name as a key
  src: {
    // Because it's a directory, add the "directory" key
    directory: {
      // This is a file - provide its path as a key:
      'main.js': {
        // Because it's a file, add the "file" key
        file: {
          contents: `
            console.log('Hello from WebContainers!')
          `,
        },
      },
      // This is another file inside the same folder
      'main.css': {
        // Because it's a file, add the "file" key
        file: {
          contents: `
            body {
              margin: 0;
            }
          `,
        },
      },
    },
  },
  // This is a file outside the folder
  'package.json': {
    /* Omitted for brevity */
  },
  // This is another file outside the folder
  'index.html': {
    /* Omitted for brevity */
  },
};

await webcontainerInstance.mount(files);
```

--------------------------------

### Represent a directory in WebContainer's file system (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Illustrates how to represent a directory in the WebContainer's virtual file system. It shows the structure for defining a directory and preparing it to contain files.

```javascript
const files = {
  src: {
    directory: {
    },
  },
};
```

--------------------------------

### Generate and Mount Binary Snapshots in WebContainers

Source: https://webcontainers.io/guides/working-with-the-file-system

Explains how to generate a binary snapshot of a source code folder using `@webcontainer/snapshot` and serve it. The client-side application can then fetch this snapshot and mount it into a WebContainer instance, enabling efficient transfer of large codebases.

```typescript
import { snapshot } from '@webcontainer/snapshot';

// snapshot is a `Buffer`
const folderSnapshot = await snapshot(SOURCE_CODE_FOLDER);

// for an express-based application
app.get('/snapshot', (req, res) => {
  res
    .setHeader('content-type', 'application/octet-stream')
    .send(snapshot);
});

// for a SvelteKit-like application
export function getSnapshot(req: Request) {
  return new Response(sourceSnapshot, {
    headers: {
      'content-type': 'application/octet-stream',
    },
  });
}
```

```typescript
import { WebContainer } from '@webcontainer/api';

const webcontainer = await WebContainer.boot();

const snapshotResponse = await fetch('/snapshot');
const snapshot = await snapshotResponse.arrayBuffer();

await webcontainer.mount(snapshot);
```

--------------------------------

### Create Directory (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Creates a directory at the specified path. If the directory already exists, an error will be thrown. The `recursive: true` option allows for the creation of nested directories in a single call.

```javascript
await webcontainerInstance.fs.mkdir('src');
```

```javascript
await webcontainerInstance.fs.mkdir('src');
```

--------------------------------

### Configure Specific Page Headers in Nuxt 3 (nuxt.config.js)

Source: https://webcontainers.io/guides/configuring-headers

This Nuxt 3 example configures Cross-Origin Isolation headers for a specific page, '/tutorial', using `nuxt.config.js`. By specifying the route '/tutorial' in `nitro.routeRules`, the headers are applied only to that particular path, providing targeted security settings.

```javascript
// https://nuxt.com/docs/api/configuration/nuxt-config
export default defineNuxtConfig({
  nitro: {
    routeRules: {
      '/tutorial': {
        headers: {
          'Cross-Origin-Embedder-Policy': 'require-corp',
          'Cross-Origin-Opener-Policy': 'same-origin',
        },
      },
    },
  },
});
```

--------------------------------

### Mounting Multiple Files in WebContainer JS

Source: https://webcontainers.io/guides/working-with-the-file-system

Demonstrates how to load multiple files into a WebContainer instance by providing an object with file paths as keys to the `mount` method. Each file object contains its content. This is useful for setting up project structures.

```javascript
/** @type {import('@webcontainer/api').FileSystemTree} */

const files = {
  'package.json': {
    file: {
      contents: `
        {
          "name": "vite-starter",
          "private": true,
          "version": "0.0.0",
          "type": "module",
          "scripts": {
            "dev": "vite",
            "build": "vite build",
            "preview": "vite preview"
          },
          "devDependencies": {
            "vite": "^4.0.4"
          }
        }`,
    },
  },
  'index.html': {
    file: {
      contents: `
        <!DOCTYPE html>
        <html lang="en">
          <head>
            <meta charset="UTF-8" />
            <link rel="icon" type="image/svg+xml" href="/vite.svg" />
            <meta name="viewport" content="width=device-width, initial-scale=1.0" />
            <title>Vite App</title>
          </head>
          <body>
            <div id="app"></div>
            <script type="module" src="/src/main.js"></script>
          </body>
        </html>`,
    },
  },
};

await webcontainerInstance.mount(files);
```

--------------------------------

### Mount a single file into WebContainer's file system (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Loads a single file, `package.json`, into the root of the WebContainer's virtual file system using the `mount` method. Requires the `webcontainerInstance` to be initialized.

```javascript
/** @type {import('@webcontainer/api').FileSystemTree} */

const files = {
  'package.json': {
    file: {
      contents: `
        {
          "name": "vite-starter",
          "private": true,
          "version": "0.0.0",
          "type": "module",
          "scripts": {
            "dev": "vite",
            "build": "vite build",
            "preview": "vite preview"
          },
          "devDependencies": {
            "vite": "^4.0.4"
          }
        }`,
    },
  },
};

await webcontainerInstance.mount(files);
```

--------------------------------

### rm - Remove File or Directory

Source: https://webcontainers.io/guides/working-with-the-file-system

Deletes a file or a directory. For directories, a `recursive: true` option is required to delete its contents.

```APIDOC
## DELETE /fs/rm

### Description
Deletes a file or a directory. If the path points to a file, the file is deleted. If the path points to a directory, the `recursive: true` option must be provided to delete the directory and all its contents.

### Method
DELETE

### Endpoint
`/fs/rm`

### Parameters
#### Query Parameters
- **path** (string) - Required - The path to the file or directory to remove.
- **options** (object) - Optional - Options for removal.
  - **recursive** (boolean) - Required if removing a directory. If true, deletes the directory and its contents.
  - **force** (boolean) - Optional - If true, ignores errors if a specified file does not exist.

### Request Example
```js
// Delete a file
await webcontainerInstance.fs.rm('/src/main.js');

// Delete a directory
await webcontainerInstance.fs.rm('/src', { recursive: true });
```

### Response
#### Success Response (204)
No content is returned upon successful deletion.
```

--------------------------------

### Read a file from WebContainer's file system (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Reads the content of a file, specifically `/package.json`, from the WebContainer's virtual file system using the `readFile` method.

```javascript
const file = await webcontainerInstance.fs.readFile('/package.json');
```

--------------------------------

### readdir - encoding Option

Source: https://webcontainers.io/guides/working-with-the-file-system

Allows specifying the encoding for the directory entries returned by `readdir`. By default, it returns strings. Setting encoding to 'buffer' returns `UInt8Array`.

```APIDOC
## GET /fs/readdir (with encoding)

### Description
Reads the contents of a directory with a specified encoding. By default, `readdir` returns an array of strings. You can pass the `encoding` option to specify the encoding, such as 'buffer' to receive `UInt8Array`.

### Method
GET

### Endpoint
`/fs/readdir`

### Parameters
#### Query Parameters
- **path** (string) - Required - The path to the directory to read.
- **encoding** (string) - Optional - Specifies the encoding. Use 'buffer' to receive `UInt8Array`. Defaults to 'utf8'.

### Request Example
```js
const files = await webcontainerInstance.fs.readdir('/src', { encoding: 'buffer' });
```

### Response
#### Success Response (200)
- **files** (array) - An array of file and directory names. If encoding is 'buffer', the array contains `UInt8Array` objects.

#### Response Example
```json
[
  // Example for encoding: 'buffer'
  "<Buffer 69 6e 64 65 78 2e 68 74 6d 6c>",
  "<Buffer 73 72 63>"
]
```
```

--------------------------------

### File System Operations (fs)

Source: https://webcontainers.io/guides/working-with-the-file-system

Details the available file system operations exposed via the `fs` property on the WebContainer instance, including `readFile`, `readdir`, `rm`, `writeFile`, and `mkdir`.

```APIDOC
## File System Operations (`fs`)

### Description
Provides an interface for interacting with the WebContainer's file system. Supported methods include `readFile`, `readdir`, `rm`, `writeFile`, and `mkdir`.

### `fs.readFile(path: string, encoding?: string): Promise<UInt8Array | string>`

Reads the file at the given path. Throws an error if the file does not exist.

- **Parameters**:
  - `path` (`string`): The path to the file to read.
  - `encoding` (`string`, optional): The encoding to use when reading the file. If not provided, returns a `UInt8Array`.

- **Returns**: A `UInt8Array` or a `string` (if encoding is specified).

- **Example**:
  ```javascript
  // Read as UInt8Array
  const fileContent = await webcontainerInstance.fs.readFile('/package.json');

  // Read as string
  const fileContentString = await webcontainerInstance.fs.readFile('/package.json', 'utf-8');
  ```

### `fs.readdir(path: string, options?: { withFileTypes?: boolean, encoding?: string }): Promise<string[] | Dirent[]>`

Reads a directory and returns an array of its files and directories. Throws an error if the directory does not exist.

- **Parameters**:
  - `path` (`string`): The path to the directory to read.
  - `options` (`object`, optional): An options object.
    - `withFileTypes` (`boolean`): If true, the reply will be an array of fs.Dirent:
    - `encoding` (`string`): Specifies the encoding of the file or directory names.

- **Returns**: An array of strings (file/directory names) or `fs.Dirent` objects.

- **Example**:
  ```javascript
  // Read directory entries as strings
  const files = await webcontainerInstance.fs.readdir('/src');

  // Read directory entries with file types
  const filesWithTypes = await webcontainerInstance.fs.readdir('/src', { withFileTypes: true });
  ```

### `fs.rm(path: string, options?: { recursive?: boolean, force?: boolean }): Promise<void>`

Removes a file or directory. Use with caution, especially with `recursive: true`.

- **Parameters**:
  - `path` (`string`): The path to the file or directory to remove.
  - `options` (`object`, optional): An options object.
    - `recursive` (`boolean`): If true, operations will be performed recursively.
    - `force` (`boolean`): If true, suppresses errors if the path does not exist.

### `fs.writeFile(path: string, data: string | Buffer | UInt8Array, options?: { encoding?: string, mode?: number, flag?: number }): Promise<void>`

Writes data to a file, replacing the file if it already exists.

- **Parameters**:
  - `path` (`string`): The path to the file to write.
  - `data` (`string | Buffer | UInt8Array`): The data to write to the file.
  - `options` (`object`, optional): An options object for encoding, mode, and flag.

### `fs.mkdir(path: string, options?: { recursive?: boolean }): Promise<void>`

Creates a directory.

- **Parameters**:
  - `path` (`string`): The path of the directory to create.
  - `options` (`object`, optional): An options object.
    - `recursive` (`boolean`): If true, creates parent directories as needed.
```

--------------------------------

### readdir - withFileTypes Option

Source: https://webcontainers.io/guides/working-with-the-file-system

Reads the contents of a directory. When `withFileTypes` is set to `true`, the method returns an array of `Dirent` objects, each containing file name and type information.

```APIDOC
## GET /fs/readdir

### Description
Reads the contents of a directory. When `withFileTypes` is set to `true`, the method returns an array of `Dirent` objects.

### Method
GET

### Endpoint
`/fs/readdir`

### Parameters
#### Query Parameters
- **path** (string) - Required - The path to the directory to read.
- **withFileTypes** (boolean) - Optional - If true, returns `Dirent` objects. Defaults to false.
- **encoding** (string) - Optional - Specifies the encoding for the file names. Defaults to 'utf8'. Can be 'buffer' to return `UInt8Array`.

### Request Example
```js
const files = await webcontainerInstance.fs.readdir('/src', {
  withFileTypes: true
});
```

### Response
#### Success Response (200)
- **files** (array) - An array of file and directory names, or `Dirent` objects if `withFileTypes` is true.
  - **Dirent Object Properties**:
    - **name** (string) - The name of the file or directory.
    - **isFile()** (function) - Returns true if the entry is a file.
    - **isDirectory()** (function) - Returns true if the entry is a directory.

#### Response Example
```json
[
  {
    "name": "index.html",
    "isFile": () => true,
    "isDirectory": () => false
  },
  {
    "name": "src",
    "isFile": () => false,
    "isDirectory": () => true
  }
]
```
```

--------------------------------

### Write File (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Writes content to a file at the specified path. If the file does not exist, it will be created. If it already exists, its content will be overwritten. An optional third argument can specify the encoding of the file content.

```javascript
await webcontainerInstance.fs.writeFile('/src/main.js', 'console.log("Hello from WebContainers!")');
```

```javascript
await webcontainerInstance.fs.writeFile('/src/main.js', 'console.log("Hello from WebContainers!")');
```

--------------------------------

### Represent a folder with a file in WebContainer's file system (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Shows how to represent a directory containing a file within the WebContainer's virtual file system. This includes defining the directory and then a nested file with its content.

```javascript
const files = {
  src: {
    directory: {
      'main.js': {
        file: {
          contents: `
            console.log('Hello from WebContainers!')
          `,
        },
      },
    },
  },
};
```

--------------------------------

### Mount Files to a Custom Path in WebContainers

Source: https://webcontainers.io/guides/working-with-the-file-system

Demonstrates how to mount a file system tree to a specific directory within the WebContainer using the `mountPoint` option. Ensures the target directory exists before mounting to prevent errors. This method is useful for organizing project files or mounting external resources to non-root locations.

```javascript
/** @type {import('@webcontainer/api').FileSystemTree} */

const files = {
  'package.json': {
    /* Omitted for brevity */
  },
  'index.html': {
    /* Omitted for brevity */
  },
};

await webcontainerInstance.mount(files, { mountPoint: 'my-mount-point' });
```

```javascript
await webcontainerInstance.fs.mkdir('my-mount-point');
await webcontainerInstance.mount(files, { mountPoint: 'my-mount-point' });
```

--------------------------------

### Represent a JSON file in WebContainer's file system (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Demonstrates the data structure for representing a single file, specifically a `package.json`, within the WebContainer's virtual file system. It shows how to define the file path and its content.

```javascript
const files = {
  'package.json': {
    file: {
      contents: `
        {
          "name": "vite-starter",
          "private": true,
         // ...
          },
          "devDependencies": {
            "vite": "^4.0.4"
          }
        }`,
    },
  },
};
```

--------------------------------

### Read File Content with Encoding in WebContainers

Source: https://webcontainers.io/guides/working-with-the-file-system

Illustrates how to read the content of a file from the WebContainer's file system using `webcontainerInstance.fs.readFile`. It shows how to retrieve the content as a `UInt8Array` by default, or as a string when a specific encoding like 'utf-8' is provided.

```javascript
const file = await webcontainerInstance.fs.readFile('/package.json');
//    ^ it is a UInt8Array
```

```javascript
const file = await webcontainerInstance.fs.readFile('/package.json', 'utf-8');
//    ^ it is a string
```

--------------------------------

### Create Nested Directory Recursively (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Creates a nested directory structure in a single operation using the `recursive: true` option. This is convenient for setting up complex directory layouts without needing to create each directory individually.

```javascript
await webcontainerInstance.fs.mkdir('this/is/my/nested/folder', { recursive: true });
```

```javascript
await webcontainerInstance.fs.mkdir('this/is/my/nested/folder', { recursive: true });
```

--------------------------------

### Read Directory with Encoding Option (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Reads the contents of a directory and allows specifying the encoding of the returned file names. By default, `readdir` returns an array of strings. When `encoding` is set to 'buffer', it returns an array of `UInt8Array`.

```javascript
const files = await webcontainerInstance.fs.readdir('/src', { encoding: 'buffer' });
//    ^ it is an array of UInt8Array
```

```javascript
const files = await webcontainerInstance.fs.readdir('/src', { encoding: 'buffer' });
//    ^ it is an array of UInt8Array
```

--------------------------------

### Remove File or Directory (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Deletes a file or a directory. For files, a simple path is sufficient. For directories, the `recursive: true` option must be provided to delete the directory and all its contents. The `force` option can also be used for deletion.

```javascript
// Delete a file
await webcontainerInstance.fs.rm('/src/main.js');

// Delete a directory
await webcontainerInstance.fs.rm('/src', { recursive: true });
```

```javascript
// Delete a file
await webcontainerInstance.fs.rm('/src/main.js');

// Delete a directory
await webcontainerInstance.fs.rm('/src', { recursive: true });
```

--------------------------------

### Read Directory with File Types (JavaScript)

Source: https://webcontainers.io/guides/working-with-the-file-system

Reads the contents of a directory and returns an array of `Dirent` objects. Each `Dirent` object contains information about the file or directory, such as its name and type (file or directory). This is useful for distinguishing between files and subdirectories without needing to perform additional file system operations.

```javascript
const files = await webcontainerInstance.fs.readdir('/src', {
  withFileTypes: true,
});
```

```javascript
const files = await webcontainerInstance.fs.readdir('/src', {
  withFileTypes: true,
});
```

--------------------------------

### Run Command in Specific Directory with WebContainer

Source: https://webcontainers.io/guides/troubleshooting

This code snippet shows how to execute a command within a specific directory using the WebContainer API's `spawn` method. It demonstrates passing the `--cwd` flag to the `turbo` command, followed by the desired project path and the actual command to execute (e.g., `astro dev`). This is useful for managing multiple projects or running commands in isolated environments.

```javascript
webcontainer.spawn('turbo', ['--cwd', `~/projects/${id}`, 'exec', 'astro', 'dev']);
```

```javascript
webcontainer.spawn('turbo', ['--cwd', `~/projects/${id}`, 'exec', 'astro', 'dev']);
```

--------------------------------

### Configure All Page Headers in Next.js (next.config.js)

Source: https://webcontainers.io/guides/configuring-headers

This Next.js configuration sets Cross-Origin Isolation headers for all pages using the `headers` function in `next.config.js`. The `source: '/(.*)'` pattern targets all incoming requests, applying the specified headers globally across the application.

```javascript
// https://nextjs.org/docs/api-reference/next.config.js/introduction
module.exports = {
  async headers() {
    return [
      {
        source: '/(.*)',
        headers: [
          {
            key: 'Cross-Origin-Embedder-Policy',
            value: 'require-corp',
          },
          {
            key: 'Cross-Origin-Opener-Policy',
            value: 'same-origin',
          },
        ],
      },
    ];
  },
};
```

--------------------------------

### Configure All Page Headers in SvelteKit (hooks.server.js)

Source: https://webcontainers.io/guides/configuring-headers

This snippet configures Cross-Origin Isolation headers for all pages in a SvelteKit application by modifying the `hooks.server.js` file. It intercepts requests and adds the required headers to the response. This is useful for ensuring consistent security policies across your entire site.

```javascript
export const handle = async ({ request, resolve }) => {
  const response = await resolve(request);

  response.headers.set('Cross-Origin-Embedder-Policy', 'require-corp');
  response.headers.set('Cross-Origin-Opener-Policy', 'same-origin');

  return response;
};
```

--------------------------------

### Reading Process Output in WebContainers

Source: https://webcontainers.io/guides/running-processes

Shows how to capture and process the output of a spawned process in WebContainers. The `output` property of the `WebContainerProcess` is piped to a `WritableStream` to log the data to the console.

```javascript
  const installProcess = await webcontainerInstance.spawn('npm', ['install']);

  installProcess.output.pipeTo(new WritableStream({
    write(data) {
      console.log(data);
    }
  }));
```

--------------------------------

### Configure Specific Page Headers in SvelteKit (+page.server.js)

Source: https://webcontainers.io/guides/configuring-headers

This SvelteKit code demonstrates setting Cross-Origin Isolation headers for a specific page using its `+page.server.js` file. The `setHeaders` function is used within the `load` export to directly configure headers for that particular route. This method is cleaner for single-page header configurations.

```javascript
/** @type {import('./$types').PageServerLoad} */
export const load = ({ setHeaders }) => {
  setHeaders({
    'Cross-Origin-Embedder-Policy': 'require-corp',
    'Cross-Origin-Opener-Policy': 'same-origin',
  });
};
```

--------------------------------

### Configure All Page Headers in Nuxt 3 (nuxt.config.js)

Source: https://webcontainers.io/guides/configuring-headers

This Nuxt 3 configuration sets Cross-Origin Isolation headers for all pages by utilizing the `nitro.routeRules` in `nuxt.config.js`. The `'**'` pattern ensures that the headers are applied globally to every route within the application.

```javascript
// https://nuxt.com/docs/api/configuration/nuxt-config
export default defineNuxtConfig({
  nitro: {
    routeRules: {
      '**': {
        headers: {
          'Cross-Origin-Embedder-Policy': 'require-corp',
          'Cross-Origin-Opener-Policy': 'same-origin',
        },
      },
    },
  },
});
```

--------------------------------

### Configure Page-Specific Headers in Next.js

Source: https://webcontainers.io/guides/configuring-headers

This snippet shows how to define custom HTTP headers for a specific route ('/tutorial') in a Next.js application. It uses the `headers` function within `next.config.js` to return an array of header configurations. The configuration includes the `source` path and an array of `headers` with their respective `key` and `value`.

```javascript
// https://nextjs.org/docs/api-reference/next.config.js/introduction
module.exports = {
  async headers() {
    return [
      {
        source: '/tutorial',
        headers: [
          {
            key: 'Cross-Origin-Embedder-Policy',
            value: 'require-corp',
          },
          {
            key: 'Cross-Origin-Opener-Policy',
            value: 'same-origin',
          },
        ],
      },
    ];
  },
};

```

--------------------------------

### Add CORS Headers with Vite Plugin

Source: https://webcontainers.io/guides/troubleshooting

This JavaScript code snippet demonstrates how to add Cross-Origin Opener Policy (COOP), Cross-Origin Embedder Policy (COEP), and Cross-Origin Resource Policy (CORP) headers using a Vite plugin. This is useful for ensuring cross-origin isolation, which is required for certain WebContainer features. The plugin configures the server middleware to set these headers for all responses.

```javascript
{
  name: 'add-cors',

  configureServer(server) {
    server.middlewares.use((_req, res, next) => {
      res.setHeader('Cross-Origin-Opener-Policy', 'same-origin');
      res.setHeader('Cross-Origin-Embedder-Policy', 'require-corp');
      res.setHeader('Cross-Origin-Resource-Policy', 'cross-origin');
      next();
    });
  },
}
```

```javascript
{
  name: 'add-cors',

  configureServer(server) {
    server.middlewares.use((_req, res, next) => {
      res.setHeader('Cross-Origin-Opener-Policy', 'same-origin');
      res.setHeader('Cross-Origin-Embedder-Policy', 'require-corp');
      res.setHeader('Cross-Origin-Resource-Policy', 'cross-origin');
      next();
    });
  },
}
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.