feat(auth): 微信登录 bind_ticket 令牌 + 配置

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/core/config.py

@@ -44,6 +44,9 @@ class Settings(BaseSettings):
     JWT_ALGORITHM: str = "HS256"
     JWT_ACCESS_TOKEN_EXPIRE_MINUTES: int = 120
     JWT_REFRESH_TOKEN_EXPIRE_DAYS: int = 30
+    # 微信登录未命中 openid 时签发的"待绑手机"令牌有效期(分钟)。
+    # 见 auth.wechat_login / security.create_bind_ticket。
+    WECHAT_BIND_TICKET_EXPIRE_MINUTES: int = 10
 
     # ===== Admin 后台 =====
     # admin 用独立 JWT secret(≠ JWT_SECRET_KEY),App 用户 token 无法越权访问后台。

app/core/security.py

@@ -87,6 +87,45 @@ def issue_token_pair(user_id: int) -> dict[str, Any]:
     }
 
 
+def create_bind_ticket(
+    *, openid: str, wechat_nickname: str | None, wechat_avatar_url: str | None
+) -> str:
+    """微信登录未命中 openid 时,签发短时"待绑手机"令牌,承载 openid + 微信昵称头像。
+
+    typ='wechat_bind'、sub=openid;有效期 settings.WECHAT_BIND_TICKET_EXPIRE_MINUTES 分钟。
+    与 access/refresh 用同一 JWT_SECRET_KEY 签名,靠 typ 区分,decode_bind_ticket 校验 typ。
+    """
+    now = _now()
+    expire = now + timedelta(minutes=settings.WECHAT_BIND_TICKET_EXPIRE_MINUTES)
+    payload: dict[str, Any] = {
+        "sub": openid,
+        "typ": "wechat_bind",
+        "wnk": wechat_nickname,
+        "wav": wechat_avatar_url,
+        "iat": int(now.timestamp()),
+        "exp": int(expire.timestamp()),
+    }
+    return jwt.encode(payload, settings.JWT_SECRET_KEY, algorithm=settings.JWT_ALGORITHM)
+
+
+def decode_bind_ticket(token: str) -> dict[str, Any]:
+    """解析"待绑手机"令牌,校验签名/过期/类型。失败抛 TokenError。
+
+    返回 {'openid': str, 'wnk': str|None, 'wav': str|None}。
+    """
+    try:
+        payload = jwt.decode(token, settings.JWT_SECRET_KEY, algorithms=[settings.JWT_ALGORITHM])
+    except jwt.ExpiredSignatureError as e:
+        raise TokenError("bind ticket expired") from e
+    except jwt.InvalidTokenError as e:
+        raise TokenError(f"invalid bind ticket: {e}") from e
+    if payload.get("typ") != "wechat_bind":
+        raise TokenError(f"wrong token type: want=wechat_bind got={payload.get('typ')}")
+    if "sub" not in payload:
+        raise TokenError("bind ticket missing sub")
+    return {"openid": payload["sub"], "wnk": payload.get("wnk"), "wav": payload.get("wav")}
+
+
 # ===================== 密码 hash(admin 后台账号用)=====================
 # 用户侧是手机号+验证码登录,不存密码;仅 admin 账号用 username+password 登录。
 

tests/test_wechat_login.py

@@ -0,0 +1,44 @@
+"""微信登录 M1 测试:bind_ticket 令牌、wechat-login(openid 命中/未命中)、
+bind-phone(建号/占用/令牌过期)。
+
+沿用 tests/test_auth.py 风格:HTTP 走 client fixture;微信 code→openid 用 monkeypatch
+拦掉(conftest 里 WECHAT_APP_ID/SECRET 是 dummy,不真连微信);短信走 SMS_MOCK(任意 6 位通过)。
+"""
+from __future__ import annotations
+
+import pytest
+
+from app.api.v1 import auth
+from app.core import security
+from app.integrations import wxpay
+
+
+def _fake_userinfo(openid: str, nickname: str | None = "微信昵称", avatar: str | None = "http://x/a.png"):
+    """返回一个可传给 monkeypatch 的假 code_to_userinfo(忽略 code,固定返回给定 openid)。"""
+    def _f(code: str) -> dict:
+        return {"openid": openid, "nickname": nickname, "avatar_url": avatar, "raw": {}}
+    return _f
+
+
+# ===== Task 1: bind_ticket 令牌 =====
+
+def test_bind_ticket_roundtrip() -> None:
+    token = security.create_bind_ticket(openid="oid1", wechat_nickname="昵", wechat_avatar_url="http://a")
+    claims = security.decode_bind_ticket(token)
+    assert claims["openid"] == "oid1"
+    assert claims["wnk"] == "昵"
+    assert claims["wav"] == "http://a"
+
+
+def test_bind_ticket_wrong_type_rejected() -> None:
+    # 用 access token 冒充 bind_ticket → TokenError(typ 不匹配)
+    access, _ = security.create_token(user_id=1, token_type="access")
+    with pytest.raises(security.TokenError):
+        security.decode_bind_ticket(access)
+
+
+def test_bind_ticket_expired_rejected(monkeypatch) -> None:
+    monkeypatch.setattr(security.settings, "WECHAT_BIND_TICKET_EXPIRE_MINUTES", -1)
+    token = security.create_bind_ticket(openid="oid", wechat_nickname=None, wechat_avatar_url=None)
+    with pytest.raises(security.TokenError):
+        security.decode_bind_ticket(token)