hello_js_reverse_skill/tcaptcha/protocol/transport.py

# -*- coding: utf-8 -*-
"""
HTTP 传输层可选实现 —— 为 `TencentCaptchaClient` 提供"浏览器级"传输指纹。

背景 (2026-10-11 实测, 见 har/1ms_dianxuan/ANALYSIS.md §7.6):
  同一 aid (1ms 195672344)、同一套腾讯云登录 cookie、同一 prehandle 参数下,
  **真实浏览器**对 cap_union_new_verify 只会得到 50 / 9 / 0 (从不 12);
  而 httpx 客户端(HTTP/1.1 + OpenSSL, 头序与浏览器不同) 永远得到 12。
  即 12 的自变量不在"载荷内容"(答案已对、密钥已用真机密钥), 而在"谁在发这个 HTTP"。

本模块用 curl_cffi 复刻 Chrome 的网络指纹(**JA3/JA4 + HTTP/2 + 头序 + 头大小写**),
对上层暴露与 `httpx.Client` 相同的最小接口 (get / post / close), 便于单变量对照。

用法::

    TencentCaptchaClient(..., transport="curl", impersonate="chrome")

依赖: `curl_cffi` (uv add curl_cffi)。
"""
from __future__ import annotations

import logging
from typing import Any, Dict, Optional

logger = logging.getLogger("tcaptcha_http")

try:                                        # 依赖可选: 未安装时只影响 transport="curl"
    from curl_cffi import requests as _cr
except Exception:                           # pragma: no cover
    _cr = None


class CurlCffiClient:
    """`httpx.Client` 的最小兼容壳 —— 走 curl_cffi 的浏览器指纹。"""

    def __init__(self, base_url: str, headers: Dict[str, str], timeout: float = 15.0,
                 proxy: Optional[str] = None, impersonate: str = "chrome",
                 follow_redirects: bool = True) -> None:
        if _cr is None:
            raise RuntimeError("curl_cffi 未安装: 先执行 `uv add curl_cffi`")
        self._base = base_url.rstrip("/")
        self._headers = {k: v for k, v in headers.items() if v is not None}
        self._timeout = timeout
        self._proxy = proxy
        self._follow = follow_redirects
        self._session = _cr.Session(impersonate=impersonate)
        logger.debug("CurlCffiClient 就绪 (impersonate=%s)", impersonate)

    # ------------------------------------------------------------------ 兼容面
    def _url(self, path: str) -> str:
        return path if str(path).startswith("http") else self._base + str(path)

    def _proxy_kw(self) -> Dict[str, Any]:
        if not self._proxy:
            return {}
        return {"proxies": {"http": self._proxy, "https": self._proxy}}

    def _merge(self, extra: Optional[Dict[str, str]]) -> Dict[str, str]:
        out = dict(self._headers)
        if extra:
            out.update({k: v for k, v in extra.items() if v is not None})
        return out

    def get(self, path: str, **kw: Any):
        headers = self._merge(kw.pop("headers", None))
        return self._session.get(self._url(path), headers=headers, timeout=self._timeout,
                                 allow_redirects=self._follow, **self._proxy_kw(), **kw)

    def post(self, path: str, **kw: Any):
        headers = self._merge(kw.pop("headers", None))
        return self._session.post(self._url(path), headers=headers, timeout=self._timeout,
                                  allow_redirects=self._follow, **self._proxy_kw(), **kw)

    def close(self) -> None:
        try:
            self._session.close()
        except Exception:                    # pragma: no cover
            pass