Edge Computing: Uma Experiência Única de Velocidade e Segurança

                                            
'use strict';

// Upstream URLs
const UPSTREAM_URLS = [
    new URL("http://localhost:4000"),
    new URL("http://localhost:4001"),
    new URL("http://localhost:4002"),
    new URL("http://localhost:4003"),
];

let NEXT_UPSTREAM_INDEX = 0;
async function handleRequest(request) {
    let upstreamIdx = NEXT_UPSTREAM_INDEX;
    NEXT_UPSTREAM_INDEX = (NEXT_UPSTREAM_INDEX + 1) % UPSTREAM_URLS.length;
    let upstream = UPSTREAM_URLS[upstreamIdx];
    return await doRequest(request, upstream);
}
function doRequest(request, upstream) {
    let newUrl = new URL(request.url);
    newUrl.protocol = upstream.protocol;
    newUrl.host = upstream.host;
    let newReq = new Request(newUrl.toString(), request);
    return fetch(newReq);
}

addEventListener("fetch", (event) => {
    event.respondWith(handleRequest(event.request));
});
                                        

                                            
'use strict';

// Your domains that is allowed to access hotlinks
const DOMAINS = ["time.ir", "fa.wikipedia.org"];
// Upstream url
const UPSTREAM_URL = "http://localhost:4000";
// File extensions that hotlink is against
const EXTENSIONS = ["jpg", "jpeg", "png", "ico", "gif"];

async function handleRequest(request) {
    const fileExt = extractUrlFileExtension(request.url);
    if (fileExt == null || !EXTENSIONS_SET.has(fileExt)) {
        return await doRequest(request);
    }
    else {
        return await checkReferrerAndDoRequest(request);
    }
}
async function doRequest(request) {
    let newUrl = new URL(request.url);
    newUrl.protocol = UPSTREAM_PROTOCOL;
    newUrl.host = UPSTREAM_HOST;
    let newReq = new Request(newUrl.toString(), request);
    return fetch(newReq);
}
async function checkReferrerAndDoRequest(request) {
    let response;
    const referrerHeader = request.headers.get("referer");
    if (referrerHeader != null) {
        let domain = extractDomainFromReferrer(referrerHeader);
        if (domain == null || DOMAINS_SET.has(domain)) {
            response = await doRequest(request);
        }
        else {
            response = UNAUTHORIZED_RESPONSE;
        }
    }
    else {
        response = await doRequest(request);
    }
    return response;
}
function extractDomainFromReferrer(referrer) {
    try {
        return new URL(referrer).hostname;
    }
    catch (e) {
        return null;
    }
}
function extractUrlFileExtension(url) {
    try {
        let pathname = new URL(url).pathname;
        let lastDotIdx = pathname.lastIndexOf(".");
        if (lastDotIdx == -1) {
            return null;
        }
        else {
            return pathname.substring(1 + lastDotIdx);
        }
    }
    catch (e) {
        return null;
    }
}
const DOMAINS_SET = (() => {
    const set = new Set();
    DOMAINS.forEach((i) => set.add(i));
    return set;
})();
const EXTENSIONS_SET = (() => {
    const set = new Set();
    EXTENSIONS.forEach((i) => set.add(i));
    return set;
})();
const UNAUTHORIZED_RESPONSE = new Response(null, {
    status: 401,
});
const UPSTREAM_PROTOCOL = new URL(UPSTREAM_URL).protocol;
const UPSTREAM_HOST = new URL(UPSTREAM_URL).host;

addEventListener("fetch", (event) => {
    event.respondWith(handleRequest(event.request));
});
                                        

                                            
'use strict';

// Credentials for users
const UserPassList = [{ user: "admin", pass: "adminpass" }];
// Upstream url
const UPSTREAM_URL = "http://localhost:4000";

async function handleRequest(request) {
    const authHeader = request.headers.get("Authorization");
    let response;
    if (authHeader != null && authHeader.startsWith("Basic")) {
        let encodedCredential = authHeader.substring(6);
        if (CREDENTIALS.has(encodedCredential)) {
            let newUrl = new URL(request.url);
            newUrl.protocol = UPSTREAM_PROTOCOL;
            newUrl.host = UPSTREAM_HOST;
            let newReq = new Request(newUrl.toString(), request);
            newReq.headers.delete("Authorization");
            response = await fetch(newReq);
        }
        else {
            response = UNAUTHORIZED_INVALID_CREDENTIALS_RESPONSE;
        }
    }
    else {
        response = UNAUTHORIZED_NEEDS_LOGIN_RESPONSE;
    }
    return response;
}
const UNAUTHORIZED_NEEDS_LOGIN_RESPONSE = new Response(null, {
    //TODO: Add realm and/or charset if needed
    headers: new Headers({
        "WWW-Authenticate": "Basic",
    }),
    status: 401,
});
const UNAUTHORIZED_INVALID_CREDENTIALS_RESPONSE = new Response(null, {
    status: 401,
});
// Key: Base64 encoded username:password
// Value: username
const CREDENTIALS = (() => {
    const map = new Map();
    for (let i of UserPassList) {
        // TODO: this may not properly work with utf8
        const encoded = btoa(`${i.user}:${i.pass}`);
        map.set(encoded, i.user);
    }
    return map;
})();
const UPSTREAM_PROTOCOL = new URL(UPSTREAM_URL).protocol;
const UPSTREAM_HOST = new URL(UPSTREAM_URL).host;

addEventListener("fetch", (event) => {
    event.respondWith(handleRequest(event.request));
});
                                        

                                            
'use strict';

const TODO_LIST = ["test"];
function createDb() {
    return {
        add: async (title) => {
            TODO_LIST.push(title);
        },
        list: async () => TODO_LIST,
    };
}
const DefaultDB = createDb();

var Index = "<!DOCTYPE html>\n<html lang=\"en\">\n\n<head>\n  <title>Todo list</title>\n  <script src=\"https://unpkg.com/htmx.org@1.9.5\"></script>\n  <link rel=\"stylesheet\" href=\"/styles.css\">\n</head>\n\n<body>\n  <div>\n    <div>\n      <h1>To-Do List</h1>\n    </div>\n    <form hx-post=\"/add\" hx-target=\"#list\" hx-swap=\"beforeend\">\n      <div>\n        <input type=\"text\" placeholder=\"Task title\" name=\"title\" required />\n        <button type=\"submit\">Add</button>\n      </div>\n    </form>\n    <div id=\"list\" hx-get=\"/list\" hx-trigger=\"load\"></div>\n  </div>\n</body>\n\n</html>";

var Styles = "h1 {\n  color: red;\n}\n";

async function handleRequest(request) {
    // simple router:
    let content = "";
    const url = new URL(request.url);
    switch (url.pathname) {
        case "/":
            content = Index;
            break;
        case "/styles.css":
            return new Response(Styles, {
                headers: { "Content-Type": "text/css" },
            });
        case "/add":
            const data = await request.formData();
            const title = data.get("title").toString();
            await DefaultDB.add(title);
            content = `<li>${title}</li>`;
            break;
        case "/list":
            content = (await DefaultDB.list()).map((x) => `<li>${x}</li>`).join("");
            break;
        default:
            content = "Not found :(";
    }
    if (request.url)
        return new Response(content, {
            headers: { "Content-Type": "text/html; charset=utf-8" },
        });
}

addEventListener("fetch", (event) => {
    event.respondWith(handleRequest(event.request));
});