/**
* DomainFront Relay — Google Apps Script
*
* TWO modes:
* 1. Single: POST { k, m, u, h, b, ct, r } → { s, h, b }
* 2. Batch: POST { k, q: [{m,u,h,b,ct,r}, ...] } → { q: [{s,h,b}, ...] }
* Uses UrlFetchApp.fetchAll() — all URLs fetched IN PARALLEL.
*
* DEPLOYMENT:
* 1. Go to https://script.google.com → New project
* 2. Delete the default code, paste THIS entire file
* 3. Click Deploy → New deployment
* 4. Type: Web app | Execute as: Me | Who has access: Anyone
* 5. Copy the Deployment ID into config.json as "script_id"
*
* CHANGE THE AUTH KEY BELOW TO YOUR OWN SECRET!
*/
const AUTH_KEY = "CHANGE_ME_TO_A_STRONG_SECRET";
// Keep browser capability headers (sec-ch-ua*, sec-fetch-*) intact.
// Some modern apps, notably Google Meet, use them for browser gating.
const SKIP_HEADERS = {
host: 1, connection: 1, "content-length": 1,
"transfer-encoding": 1, "proxy-connection": 1, "proxy-authorization": 1,
"priority": 1, te: 1,
};
function doPost(e) {
try {
var req = JSON.parse(e.postData.contents);
if (req.k !== AUTH_KEY) return _json({ e: "unauthorized" });
// Batch mode: { k, q: [...] }
if (Array.isArray(req.q)) return _doBatch(req.q);
// Single mode
return _doSingle(req);
} catch (err) {
return _json({ e: String(err) });
}
}
function _doSingle(req) {
if (!req.u || typeof req.u !== "string" || !req.u.match(/^https?:\/\//i)) {
return _json({ e: "bad url" });
}
var opts = _buildOpts(req);
var resp = UrlFetchApp.fetch(req.u, opts);
return _json({
s: resp.getResponseCode(),
h: _respHeaders(resp),
b: Utilities.base64Encode(resp.getContent()),
});
}
function _doBatch(items) {
var fetchArgs = [];
var errorMap = {};
for (var i = 0; i < items.length; i++) {
var item = items[i];
if (!item.u || typeof item.u !== "string" || !item.u.match(/^https?:\/\//i)) {
errorMap[i] = "bad url";
continue;
}
var opts = _buildOpts(item);
opts.url = item.u;
fetchArgs.push({ _i: i, _o: opts });
}
// fetchAll() processes all requests in parallel inside Google
var responses = [];
if (fetchArgs.length > 0) {
responses = UrlFetchApp.fetchAll(fetchArgs.map(function(x) { return x._o; }));
}
var results = [];
var rIdx = 0;
for (var i = 0; i < items.length; i++) {
if (errorMap.hasOwnProperty(i)) {
results.push({ e: errorMap[i] });
} else {
var resp = responses[rIdx++];
results.push({
s: resp.getResponseCode(),
h: _respHeaders(resp),
b: Utilities.base64Encode(resp.getContent()),
});
}
}
return _json({ q: results });
}
function _buildOpts(req) {
var opts = {
method: (req.m || "GET").toLowerCase(),
muteHttpExceptions: true,
followRedirects: req.r !== false,
validateHttpsCertificates: true,
escaping: false,
};
if (req.h && typeof req.h === "object") {
var headers = {};
for (var k in req.h) {
if (req.h.hasOwnProperty(k) && !SKIP_HEADERS[k.toLowerCase()]) {
headers[k] = req.h[k];
}
}
opts.headers = headers;
}
if (req.b) {
opts.payload = Utilities.base64Decode(req.b);
if (req.ct) opts.contentType = req.ct;
}
return opts;
}
function _respHeaders(resp) {
try {
if (typeof resp.getAllHeaders === "function") {
return resp.getAllHeaders();
}
} catch (err) {}
return resp.getHeaders();
}
function doGet(e) {
return HtmlService.createHtmlOutput(
"My App" +
'' +
"Welcome
This application is running normally.
" +
""
);
}
function _json(obj) {
return ContentService.createTextOutput(JSON.stringify(obj)).setMimeType(
ContentService.MimeType.JSON
);
}