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"use strict";
function handleRequest(request, response) {
let qs = new URLSearchParams(request.queryString);
let asset = qs.get("as");
let hinted = qs.get("hinted") === "1";
let httpCode = qs.get("code");
let uuid = qs.get("uuid");
let cached = qs.get("cached") === "1";
let url = `early_hint_asset.sjs?as=${asset}${uuid ? `&uuid=${uuid}` : ""}${
cached ? "&cached=1" : ""
}`;
// write to raw socket
response.seizePower();
let link = "";
if (hinted) {
response.write("HTTP/1.1 103 Early Hint\r\n");
if (asset === "fetch" || asset === "font") {
// fetch and font has to specify the crossorigin attribute
link = `Link: <${url}>; rel=preload; as=${asset}; crossorigin=anonymous\r\n`;
response.write(link);
} else if (asset === "module") {
// module preloads are handled differently
link = `Link: <${url}>; rel=modulepreload\r\n`;
response.write(link);
} else {
link = `Link: <${url}>; rel=preload; as=${asset}\r\n`;
response.write(link);
}
response.write("\r\n");
}
let body = "";
if (asset === "image") {
body = `<!DOCTYPE html>
<html>
<body>
<img src="${url}" width="100px">
</body>
</html>`;
} else if (asset === "style") {
body = `<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="${url}">
</head>
<body>
<h1>Test preload css<h1>
<div id="square" style="width:100px;height:100px;">
</body>
</html>
`;
} else if (asset === "script") {
body = `<!DOCTYPE html>
<html>
<head>
<script src="${url}"></script>
</head>
<body>
<h1>Test preload javascript<h1>
<div id="square" style="width:100px;height:100px;">
</body>
</html>
`;
} else if (asset === "module") {
// this code assumes that the .sjs for the module is in the same directory
var file_name = url.split("/");
file_name = file_name[file_name.length - 1];
body = `<!DOCTYPE html>
<html>
<head>
</head>
<body>
<h1>Test preload module<h1>
<div id="square" style="width:100px;height:100px;">
<script type="module">
import { draw } from "./${file_name}";
draw();
</script>
</body>
</html>
`;
} else if (asset === "fetch") {
body = `<!DOCTYPE html>
<html>
<body onload="onLoad()">
<script>
function onLoad() {
fetch("${url}")
.then(r => r.text())
.then(r => document.getElementsByTagName("h2")[0].textContent = r);
}
</script>
<h1>Test preload fetch</h1>
<h2>Fetching...</h2>
</body>
</html>
`;
} else if (asset === "font") {
body = `<!DOCTYPE html>
<html>
<head>
<style>
@font-face {
font-family: "preloadFont";
src: url("${url}");
}
body {
font-family: "preloadFont";
}
</style>
</head>
<body>
<h1>Test preload font<h1>
</body>
</html>
`;
}
if (!httpCode) {
response.write(`HTTP/1.1 200 OK\r\n`);
} else {
response.write(`HTTP/1.1 ${httpCode} Error\r\n`);
}
response.write(link);
response.write("Content-Type: text/html;charset=utf-8\r\n");
response.write("Cache-Control: no-cache\r\n");
response.write(`Content-Length: ${body.length}\r\n`);
response.write("\r\n");
response.write(body);
response.finish();
}