Tiny Starlette application for retrieving image files from a private S3 bucket, resizing them based on querystring parameters and serving them with cache headers so the resized images can be cached by a CDN.
See Using SQL to find my best photo of a pelican according to Apple Photos for background information on this project.
You can see a demo of this proxy in action serving images on this page.
The following environment variables are required:
S3_BUCKETS3_AWS_ACCESS_KEY_IDS3_AWS_SECRET_ACCESS_KEY
Here are some notes on creating an S3 bucket with the right credentials.
If you want to be able to access the original image files, set a ORIGINAL_TOKEN with a secret token that you plan to use to access the originals.
You can deploy this tool directly to Vercel. You'll need to set the necessary environment variables.
Vercel provides a CDN, so resized images should be served very quickly on subsequent requests to the same image.
For local development you will need to install an additional dependency: uvicorn.
pip install -r requirements.txt
pip install uvicorn
You can then run the server like this:
S3_AWS_ACCESS_KEY_ID="xxx" \
S3_AWS_SECRET_ACCESS_KEY="yyy" \
S3_BUCKET="your-bucket" \
ORIGINAL_TOKEN="your-secret-token" \
uvicorn index:app
Once up and running, you can access image files stored in the S3 bucket like so:
http://localhost:8000/i/name-of-file.jpeg
To resize the image, pass ?w= or ?h= arguments:
http://localhost:8000/i/name-of-file.jpeg?w=400
http://localhost:8000/i/name-of-file.jpeg?h=400
Use ?bw=1 to convert the image to black and white.
If you are serving JPEGs you can control the quality using ?q= - e.g. ?q=25 for a lower quality (but faster loading) image.
To access the original image file, use this URL:
http://localhost:8000/o/name-of-file.jpeg?token=YOUR_SECRET_TOKEN