将 checkout_capabilities 响应改写为 cassia
// ==UserScript==
// @name TestExample Cassia Response Mock
// @namespace local.testexample.checkout
// @version 1.1.0
// @description 将 checkout_capabilities 响应改写为 cassia
// @match *://claude.ai/*
// @match *://*.claude.ai/*
// @run-at document-start
// @grant none
// @sandbox raw
// ==/UserScript==
(function () {
"use strict";
const TARGET_HOST = "claude.ai";
const TARGET_PATH =
/^\/api\/organizations\/[^/]+\/subscription\/checkout_capabilities\/?$/;
const MOCK_DATA = {
checkout_flow: "cassia"
};
const MOCK_BODY = JSON.stringify(MOCK_DATA);
const MOCK_LENGTH =
new TextEncoder().encode(MOCK_BODY).byteLength;
function getTargetUrl(input, method = "GET") {
try {
let rawUrl;
if (typeof input === "string" || input instanceof URL) {
rawUrl = String(input);
} else if (input && typeof input.url === "string") {
rawUrl = input.url;
} else {
return null;
}
const url = new URL(rawUrl, location.href);
if (String(method).toUpperCase() !== "GET") {
return null;
}
// 允许主域名以及其子域名
const hostMatched =
url.hostname === TARGET_HOST ||
url.hostname.endsWith("." + TARGET_HOST);
if (!hostMatched) {
return null;
}
if (!TARGET_PATH.test(url.pathname)) {
return null;
}
return url;
} catch (error) {
console.error("[Cassia Mock] URL 解析失败：", error);
return null;
}
}
function createMockResponse(originalResponse) {
const headers = new Headers(originalResponse.headers);
headers.delete("content-length");
headers.delete("content-encoding");
headers.delete("etag");
headers.delete("content-md5");
headers.set(
"content-type",
"application/json; charset=utf-8"
);
headers.set("content-length", String(MOCK_LENGTH));
headers.set("cache-control", "no-store");
const response = new Response(MOCK_BODY, {
status: 200,
statusText: "OK",
headers
});
// 尽量保留原始响应信息
try {
Object.defineProperties(response, {
url: {
value: originalResponse.url,
configurable: true
},
redirected: {
value: originalResponse.redirected,
configurable: true
},
type: {
value: originalResponse.type,
configurable: true
}
});
} catch (_) {
// 不影响主体改写
}
return response;
}
/*
* 拦截 Fetch
*/
const nativeFetch = window.fetch;
window.fetch = async function (input, init) {
const method =
init?.method ||
(input instanceof Request ? input.method : "GET");
const targetUrl = getTargetUrl(input, method);
const originalResponse =
await nativeFetch.apply(this, arguments);
if (!targetUrl) {
return originalResponse;
}
console.warn(
"[Cassia Mock] Fetch 响应已改写：",
targetUrl.href,
MOCK_DATA
);
return createMockResponse(originalResponse);
};
/*
* 拦截 XMLHttpRequest
*/
const XhrPrototype = XMLHttpRequest.prototype;
const xhrInfo = new WeakMap();
const loggedXhrs = new WeakSet();
const nativeOpen = XhrPrototype.open;
const nativeSend = XhrPrototype.send;
const nativeGetResponseHeader =
XhrPrototype.getResponseHeader;
const nativeGetAllResponseHeaders =
XhrPrototype.getAllResponseHeaders;
XhrPrototype.open = function (method, url) {
let absoluteUrl;
try {
absoluteUrl = new URL(
String(url),
location.href
).href;
} catch (_) {
absoluteUrl = String(url);
}
xhrInfo.set(this, {
method: String(method || "GET").toUpperCase(),
url: absoluteUrl
});
return nativeOpen.apply(this, arguments);
};
function getMatchedXhr(xhr) {
const info = xhrInfo.get(xhr);
if (
!info ||
xhr.readyState !== XMLHttpRequest.DONE
) {
return null;
}
return getTargetUrl(info.url, info.method);
}
function replaceXhrGetter(propertyName, replacement) {
const descriptor =
Object.getOwnPropertyDescriptor(
XhrPrototype,
propertyName
);
if (
!descriptor ||
typeof descriptor.get !== "function" ||
descriptor.configurable === false
) {
console.warn(
`[Cassia Mock] 无法接管 XHR.${propertyName}`
);
return;
}
const nativeGetter = descriptor.get;
Object.defineProperty(XhrPrototype, propertyName, {
...descriptor,
get: function () {
if (!getMatchedXhr(this)) {
return nativeGetter.call(this);
}
return replacement.call(this, nativeGetter);
}
});
}
replaceXhrGetter(
"responseText",
function (nativeGetter) {
if (
this.responseType !== "" &&
this.responseType !== "text"
) {
return nativeGetter.call(this);
}
return MOCK_BODY;
}
);
replaceXhrGetter(
"response",
function (nativeGetter) {
if (this.responseType === "json") {
return {
checkout_flow: "cassia"
};
}
if (
this.responseType === "" ||
this.responseType === "text"
) {
return MOCK_BODY;
}
return nativeGetter.call(this);
}
);
replaceXhrGetter("status", function () {
return 200;
});
replaceXhrGetter("statusText", function () {
return "OK";
});
XhrPrototype.getResponseHeader = function (name) {
if (!getMatchedXhr(this)) {
return nativeGetResponseHeader.apply(
this,
arguments
);
}
switch (String(name).toLowerCase()) {
case "content-type":
return "application/json; charset=utf-8";
case "content-length":
return String(MOCK_LENGTH);
case "cache-control":
return "no-store";
case "content-encoding":
case "etag":
case "content-md5":
return null;
default:
return nativeGetResponseHeader.apply(
this,
arguments
);
}
};
XhrPrototype.getAllResponseHeaders = function () {
const originalHeaders =
nativeGetAllResponseHeaders.apply(this, arguments);
if (!getMatchedXhr(this)) {
return originalHeaders;
}
const headers = String(originalHeaders || "")
.split(/\r?\n/)
.filter(Boolean)
.filter(function (line) {
const name = line
.split(":", 1)[0]
.trim()
.toLowerCase();
return ![
"content-type",
"content-length",
"content-encoding",
"cache-control",
"etag",
"content-md5"
].includes(name);
});
headers.push(
"content-type: application/json; charset=utf-8",
`content-length: ${MOCK_LENGTH}`,
"cache-control: no-store"
);
return headers.join("\r\n") + "\r\n";
};
XhrPrototype.send = function () {
this.addEventListener(
"readystatechange",
function () {
const targetUrl = getMatchedXhr(this);
if (targetUrl && !loggedXhrs.has(this)) {
loggedXhrs.add(this);
console.warn(
"[Cassia Mock] XHR 响应已改写：",
targetUrl.href,
MOCK_DATA
);
}
}
);
return nativeSend.apply(this, arguments);
};
/*
* 显示运行标记
*/
function showStatusBadge() {
if (!document.documentElement) {
document.addEventListener(
"DOMContentLoaded",
showStatusBadge,
{ once: true }
);
return;
}
if (document.getElementById("cassia-mock-badge")) {
return;
}
const badge = document.createElement("div");
badge.id = "cassia-mock-badge";
badge.textContent = "Cassia Mock ON";
Object.assign(badge.style, {
position: "fixed",
right: "12px",
bottom: "12px",
zIndex: "2147483647",
padding: "7px 11px",
color: "#ffffff",
background: "#167c3a",
borderRadius: "6px",
fontSize: "12px",
fontFamily: "sans-serif",
boxShadow: "0 2px 8px rgba(0,0,0,.3)"
});
document.documentElement.appendChild(badge);
}
window.__cassiaMockInstalled = true;
console.info(
"[Cassia Mock] 脚本已加载：",
location.href
);
showStatusBadge();
})();