Transform responses

You can use Edge Functions to transform the content of an HTTP response. In this example, we transform the response of a request to /hello with a toUpperCase() function, using the query parameter method=transform.

This is a simple example, and for more complex transformations you may want to use HTMLRewriter.

import { Context } from "@netlify/edge-functions";

export default async (request: Request, context: Context) => {
  const url = new URL(request.url);

  // Look for the query parameter, and return if we don't find it
  if (url.searchParams.get("method") !== "transform") {
    return;
  }

  const response = await context.next();
  const text = await response.text();
  return new Response(text.toUpperCase(), response);
};

This transform Edge Function is set up to run using the method=transform query parameter on any URL

See this in action

• View the original response from /hello without a transform
• View the response from /hello dynamically transformed with an Edge Function
• The Edge Function code: transform.ts