7shi/index.html

## index.html
<!DOCTYPE html>
<html>
    <head>
        <title>File Save Test</title>
    </head>
    <body>
        <div id="result"></div>
        <script src="test.js"></script>
    </body>
</html>

## server.ts
// deno run --allow-net --allow-read --allow-write

import { serve } from "https://deno.land/std/http/server.ts";
import { serveFile } from "https://deno.land/std/http/file_server.ts";

const port = 8080;
const server = serve({ port: port });
const serverURL = `http://127.0.0.1:${port}`;
console.log(serverURL);

const te = new TextEncoder();
for await (const req of server) {
    const hostname = (req.conn.remoteAddr as Deno.NetAddr).hostname;
    console.log(hostname, req.method, req.url);
    if (hostname != "127.0.0.1") {
        req.respond({ status: 403 });
        continue;
    }
    let res: any = {};
    res.headers = new Headers();
    const origin = req.headers.get("origin");
    const acrm   = req.headers.get("access-control-request-method");
    const acrh   = req.headers.get("access-control-request-headers");
    if (origin) res.headers.set("Access-Control-Allow-Origin" , origin);
    if (acrm  ) res.headers.set("Access-Control-Allow-Methods", acrm);
    if (acrh  ) res.headers.set("Access-Control-Allow-Headers", acrh);
    switch (req.method) {
        case "GET":
            let url = req.url;
            if (url == "/end") {
                res.body = te.encode("<m>bye!</m>");
                await req.respond(res);
                server.close();
                continue;
            }
            if (url == "/") url = "/index.html";
            try {
                res = await serveFile(req, url.substring(1));
            } catch (e) {
                console.log(e);
                res.status = 404;
            }
            break;
        case "POST":
            let name = req.url.substring(1);
            try {
                Deno.statSync(name);
                console.log(name, req.contentLength, "denied");
                res.status = 403;
                break;
            } catch {}
            try {
                Deno.writeFile(name, await Deno.readAll(req.body));
                console.log(name, req.contentLength, "created");
                res.body = te.encode("<m>created</m>");
            } catch (e) {
                console.log(e);
                console.log(name, req.contentLength, "failed");
                res.status = 403;
            }
            break;
        case "OPTIONS":
            break;
        default:
            res.status = 403;
            break;
    }
    req.respond(res);
}

## test.js
function log(str) {
    result.appendChild(document.createTextNode(str));
    result.appendChild(document.createElement("br"));
}

function send(method, url, body) {
    log(`${method} ${url}`);
    return new Promise((resolve, reject) => {
        let req = new XMLHttpRequest();
        req.open(method, url);
        req.onload = () => {
            log(`response: ${req.status} ${req.response}`);
            resolve();
        };
        if (body) {
            req.send(new Blob([body], { type: "text/plain" }));
        } else {
            req.send();
        }
    });
}

(async () => {
    await send("POST", "1.txt", "hello\n");
    await send("POST", "2.txt", "world\n");
    await send("GET" , "end");
})();
	<!DOCTYPE html>
	<html>
	<head>
	<title>File Save Test</title>
	</head>
	<body>
	<div id="result"></div>
	<script src="test.js"></script>
	</body>
	</html>
	// deno run --allow-net --allow-read --allow-write

	import { serve } from "https://deno.land/std/http/server.ts";
	import { serveFile } from "https://deno.land/std/http/file_server.ts";

	const port = 8080;
	const server = serve({ port: port });
	const serverURL = `http://127.0.0.1:${port}`;
	console.log(serverURL);

	const te = new TextEncoder();
	for await (const req of server) {
	const hostname = (req.conn.remoteAddr as Deno.NetAddr).hostname;
	console.log(hostname, req.method, req.url);
	if (hostname != "127.0.0.1") {
	req.respond({ status: 403 });
	continue;
	}
	let res: any = {};
	res.headers = new Headers();
	const origin = req.headers.get("origin");
	const acrm = req.headers.get("access-control-request-method");
	const acrh = req.headers.get("access-control-request-headers");
	if (origin) res.headers.set("Access-Control-Allow-Origin" , origin);
	if (acrm ) res.headers.set("Access-Control-Allow-Methods", acrm);
	if (acrh ) res.headers.set("Access-Control-Allow-Headers", acrh);
	switch (req.method) {
	case "GET":
	let url = req.url;
	if (url == "/end") {
	res.body = te.encode("<m>bye!</m>");
	await req.respond(res);
	server.close();
	continue;
	}
	if (url == "/") url = "/index.html";
	try {
	res = await serveFile(req, url.substring(1));
	} catch (e) {
	console.log(e);
	res.status = 404;
	}
	break;
	case "POST":
	let name = req.url.substring(1);
	try {
	Deno.statSync(name);
	console.log(name, req.contentLength, "denied");
	res.status = 403;
	break;
	} catch {}
	try {
	Deno.writeFile(name, await Deno.readAll(req.body));
	console.log(name, req.contentLength, "created");
	res.body = te.encode("<m>created</m>");
	} catch (e) {
	console.log(e);
	console.log(name, req.contentLength, "failed");
	res.status = 403;
	}
	break;
	case "OPTIONS":
	break;
	default:
	res.status = 403;
	break;
	}
	req.respond(res);
	}
	function log(str) {
	result.appendChild(document.createTextNode(str));
	result.appendChild(document.createElement("br"));
	}

	function send(method, url, body) {
	log(`${method} ${url}`);
	return new Promise((resolve, reject) => {
	let req = new XMLHttpRequest();
	req.open(method, url);
	req.onload = () => {
	log(`response: ${req.status} ${req.response}`);
	resolve();
	};
	if (body) {
	req.send(new Blob([body], { type: "text/plain" }));
	} else {
	req.send();
	}
	});
	}

	(async () => {
	await send("POST", "1.txt", "hello\n");
	await send("POST", "2.txt", "world\n");
	await send("GET" , "end");
	})();