> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ouim.me/llms.txt
> Use this file to discover all available pages before exploring further.

# Cookie Utilities

> Client-side cookie management utilities for authentication

Utilities for managing cookies and JWT tokens in logto-authkit applications.

## Cookie Utilities

General-purpose cookie management functions.

### cookieUtils.setCookie

Set a cookie with the given name, value, and options.

```typescript theme={null}
cookieUtils.setCookie(
  name: string,
  value: string,
  options?: CookieOptions
): void
```

<ResponseField name="name" type="string" required>
  The cookie name
</ResponseField>

<ResponseField name="value" type="string" required>
  The cookie value
</ResponseField>

<ResponseField name="options" type="CookieOptions">
  Cookie configuration options
</ResponseField>

#### CookieOptions

<ResponseField name="expires" type="Date | number">
  Expiration date (Date object) or number of days until expiration
</ResponseField>

<ResponseField name="maxAge" type="number">
  Maximum age in seconds
</ResponseField>

<ResponseField name="domain" type="string">
  Cookie domain
</ResponseField>

<ResponseField name="path" type="string" default="/">
  Cookie path
</ResponseField>

<ResponseField name="secure" type="boolean" default="window.location.protocol === 'https:'">
  Whether cookie requires HTTPS
</ResponseField>

<ResponseField name="sameSite" type="'strict' | 'lax' | 'none'" default="lax">
  SameSite cookie attribute
</ResponseField>

<ResponseField name="httpOnly" type="boolean">
  Whether cookie is HTTP-only (not accessible via JavaScript)
</ResponseField>

**Example:**

```typescript theme={null}
import { cookieUtils } from '@ouim/logto-authkit'

// Set a cookie that expires in 7 days
cookieUtils.setCookie('user_preference', 'dark-mode', {
  expires: 7,
  secure: true,
  sameSite: 'strict'
})

// Set a cookie with a specific expiration date
cookieUtils.setCookie('session', 'abc123', {
  expires: new Date('2026-12-31'),
  path: '/'
})
```

### cookieUtils.getCookie

Get a cookie value by name.

```typescript theme={null}
cookieUtils.getCookie(name: string): string | null
```

<ResponseField name="name" type="string" required>
  The cookie name to retrieve
</ResponseField>

**Returns:** `string | null` - The cookie value, or `null` if not found

**Example:**

```typescript theme={null}
import { cookieUtils } from '@ouim/logto-authkit'

const preference = cookieUtils.getCookie('user_preference')
if (preference === 'dark-mode') {
  // Enable dark mode
}
```

### cookieUtils.removeCookie

Remove a cookie by name.

```typescript theme={null}
cookieUtils.removeCookie(
  name: string,
  options?: RemoveCookieOptions
): void
```

<ResponseField name="name" type="string" required>
  The cookie name to remove
</ResponseField>

<ResponseField name="options" type="RemoveCookieOptions">
  Cookie removal options (domain and path must match the original cookie)
</ResponseField>

#### RemoveCookieOptions

<ResponseField name="domain" type="string">
  Cookie domain (must match original)
</ResponseField>

<ResponseField name="path" type="string" default="/">
  Cookie path (must match original)
</ResponseField>

**Example:**

```typescript theme={null}
import { cookieUtils } from '@ouim/logto-authkit'

cookieUtils.removeCookie('user_preference', { path: '/' })
```

## JWT Token Utilities

Specialized utilities for managing JWT authentication tokens.

### jwtCookieUtils.saveToken

Save a JWT token to a secure cookie.

```typescript theme={null}
jwtCookieUtils.saveToken(token: string): void
```

<ResponseField name="token" type="string" required>
  The JWT token to save
</ResponseField>

**Cookie details:**

* Name: `logto_authtoken`
* Expires: 7 days
* Secure: true (HTTPS only)
* SameSite: strict
* Path: /

**Example:**

```typescript theme={null}
import { jwtCookieUtils } from '@ouim/logto-authkit'

// After successful authentication
const token = await getAccessToken()
jwtCookieUtils.saveToken(token)
```

### jwtCookieUtils.getToken

Retrieve the JWT token from the cookie.

```typescript theme={null}
jwtCookieUtils.getToken(): string | null
```

**Returns:** `string | null` - The JWT token, or `null` if not found

**Example:**

```typescript theme={null}
import { jwtCookieUtils } from '@ouim/logto-authkit'

const token = jwtCookieUtils.getToken()
if (token) {
  // Make authenticated API request
  fetch('/api/user', {
    headers: {
      Authorization: `Bearer ${token}`
    }
  })
}
```

### jwtCookieUtils.removeToken

Remove the JWT token cookie.

```typescript theme={null}
jwtCookieUtils.removeToken(): void
```

**Example:**

```typescript theme={null}
import { jwtCookieUtils } from '@ouim/logto-authkit'

// On sign out
function handleSignOut() {
  jwtCookieUtils.removeToken()
  // Redirect to login page
}
```

## Configuration Validation

### validateLogtoConfig

Validate Logto configuration for required fields.

```typescript theme={null}
validateLogtoConfig(config: LogtoConfig): void
```

<ResponseField name="config" type="LogtoConfig" required>
  The Logto configuration object to validate
</ResponseField>

**Throws:** `Error` if configuration is invalid or missing required fields

**Example:**

```typescript theme={null}
import { validateLogtoConfig } from '@ouim/logto-authkit'
import type { LogtoConfig } from '@logto/react'

const config: LogtoConfig = {
  endpoint: 'https://your-tenant.logto.app',
  appId: 'your-app-id',
  resources: ['https://api.example.com']
}

try {
  validateLogtoConfig(config)
  console.log('Config is valid')
} catch (error) {
  console.error('Invalid config:', error.message)
}
```

<Note>
  The library uses internal utilities for transforming user data and generating guest IDs. These utilities are used automatically by the AuthProvider and do not need to be called directly.
</Note>