Source code
Revision control
Copy as Markdown
Other Tools
"use strict";
function handleRequest(request, response) {
response.setHeader("Content-Type", "image/png", false);
response.setHeader("Cache-Control", "max-age=604800", false);
// the typo in "Referer" is part of the http spec
if (request.hasHeader("Referer")) {
setSharedState("requestReferrer", request.getHeader("Referer"));
} else {
setSharedState("requestReferrer", "");
}
let count = JSON.parse(getSharedState("earlyHintCount"));
let image;
// send different sized images depending whether this is an early hint request
if (
request.hasHeader("X-Moz") &&
request.getHeader("X-Moz") === "early hint"
) {
count.hinted += 1;
// set to green/black horizontal stripes (71 bytes)
image = atob(
"iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAIAAAD91JpzAAAADklEQVQIW2OU+i/FAAcADoABNV8X" +
"GBMAAAAASUVORK5CYII="
);
} else {
count.normal += 1;
// set to purple/white checkered pattern (76 bytes)
image = atob(
"iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAIAAAD91JpzAAAAE0lEQVQIW2P4//+/N8MkBiAGsgA1" +
"bAe1SzDY8gAAAABJRU5ErkJggg=="
);
}
setSharedState("earlyHintCount", JSON.stringify(count));
response.write(image);
}