Lumo Framework

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HTTP Response ​

Introduction ​

Lumo Framework provides several ways to return responses from your API handlers. You may return JSON data, plain text responses, HTML content, redirects, or even file downloads.

Creating Responses ​

Basic Responses ​

The simplest responses return JSON data using the json method:

typescript
import { Request, Response } from '@lumo-framework/core'

export function GET(request: Request, response: Response) {
  return response.json({ message: 'Hello World' })
}

You can also specify a status code as the second parameter:

typescript
export function POST(request: Request, response: Response) {
  const user = createUser(request.json())
  
  return response.json(user, 201) // Created
}

Attaching Headers ​

Add custom headers to your responses using the header method:

typescript
export function GET(request: Request, response: Response) {
  return response
    .header('X-API-Version', '2.0')
    .header('Cache-Control', 'no-cache')
    .json({ data: 'Hello World' })
}

Attaching Cookies ​

Set cookies on the response using the cookie method:

typescript
export function POST(request: Request, response: Response) {
  return response
    .cookie('session_id', 'abc123', {
      httpOnly: true,
      secure: true,
      maxAge: 3600 // 1 hour
    })
    .json({ message: 'Logged in successfully' })
}

Cookie options include:

  • maxAge: Expiration in seconds
  • expires: Explicit expiration date
  • domain: Cookie domain
  • path: Cookie path
  • secure: HTTPS only
  • httpOnly: HTTP only access
  • sameSite: SameSite policy ('strict', 'lax', or 'none')

Setting Status Codes ​

Set the HTTP status code using the status method:

typescript
export function GET(request: Request, response: Response) {
  const user = findUser(request.params.id)
  
  if (!user) {
    return response.status(404).json({
      error: 'User not found'
    })
  }
  
  return response.status(200).json(user)
}

Response Types ​

JSON Responses ​

Return JSON data using the json method:

typescript
export function GET(request: Request, response: Response) {
  const users = getAllUsers()
  
  return response.json({
    data: users,
    meta: {
      total: users.length,
      page: 1
    }
  })
}

HTML Responses ​

Return HTML content using the html method:

typescript
export function GET(request: Request, response: Response) {
  const htmlContent = `
    <!DOCTYPE html>
    <html>
      <head><title>Welcome</title></head>
      <body>
        <h1>Hello from Lumo Framework!</h1>
      </body>
    </html>
  `
  
  return response.html(htmlContent)
}

Plain Text Responses ​

Return plain text using the response body directly:

typescript
export function GET(request: Request, response: Response) {
  return response
    .header('Content-Type', 'text/plain')
    .status(200)
    // Use the Response object directly
}

File Downloads ​

Provide file downloads using the attachment method:

typescript
export function GET(request: Request, response: Response) {
  const fileData = getFileContent()
  
  return response
    .attachment('report.pdf')
    .header('Content-Type', 'application/pdf')
    // Return file data
}

Redirects ​

Basic Redirects ​

Redirect users to different URLs using the redirect method:

typescript
export function POST(request: Request, response: Response) {
  // Process form submission
  processForm(request.json())
  
  // Redirect to success page
  return response.redirect('/success')
}

Redirects with Status Codes ​

Specify the redirect status code:

typescript
export function GET(request: Request, response: Response) {
  // Permanent redirect
  return response.redirect('/new-url', 301)
  
  // Temporary redirect (default is 302)
  return response.redirect('/temporary-url', 302)
}

External Redirects ​

Redirect to external domains:

typescript
export function GET(request: Request, response: Response) {
  return response.redirect('https://external-site.com/page')
}