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Resize and optimize images on-the-fly based on URL parameters. What you’ll learn:
  • Processing binary data
  • Query parameter handling
  • Caching strategies

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Step 1: Create the Function

telnyx-edge new-func -l=python -n=image-resizer
cd image-resizer

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Step 2: Add Dependencies

Create or update requirements.txt: 
pillow>=10.0.0
httpx>=0.27.0

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Step 3: Implement the Resizer

from PIL import Image
from io import BytesIO
from urllib.parse import urlparse, parse_qs
import base64
import httpx

class Function:
    def __init__(self):
        self.client = httpx.AsyncClient()
    
    async def handler(self, request):
        params = parse_qs(urlparse(request.url).query)
        
        # Get parameters
        image_url = params.get("url", [None])[0]
        width = int(params.get("w", [0])[0]) or None
        height = int(params.get("h", [0])[0]) or None
        quality = int(params.get("q", [85])[0])
        
        if not image_url:
            return {"status": 400, "body": "Missing url parameter"}
        
        # Fetch original image
        response = await self.client.get(image_url)
        if response.status_code != 200:
            return {"status": 404, "body": "Image not found"}
        
        # Process image
        img = Image.open(BytesIO(response.content))
        
        # Resize if dimensions provided
        if width or height:
            if width and height:
                img = img.resize((width, height), Image.LANCZOS)
            elif width:
                ratio = width / img.width
                img = img.resize((width, int(img.height * ratio)), Image.LANCZOS)
            else:
                ratio = height / img.height
                img = img.resize((int(img.width * ratio), height), Image.LANCZOS)
        
        # Convert to bytes
        output = BytesIO()
        img.save(output, format="JPEG", quality=quality, optimize=True)
        
        return {
            "status": 200,
            "headers": {
                "Content-Type": "image/jpeg",
                "Cache-Control": "public, max-age=86400"
            },
            "body": base64.b64encode(output.getvalue()).decode()
        }

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Step 4: Deploy and Test

telnyx-edge ship
Test with: 
https://image-resizer-{orgId}.telnyxcompute.com/?url=https://example.com/photo.jpg&w=400&q=80