fix: stabilize production payment flow

apps/billing/payment_gateways.py

@@ -94,6 +94,25 @@ def _wechat_amount_cents(value) -> int:
     return int((_decimal_money(value) * Decimal("100")).to_integral_value())
 
 
+def _wechat_response_payload(response) -> dict:
+    if isinstance(response, dict):
+        return response
+    if isinstance(response, tuple) and len(response) >= 2:
+        payload = response[1]
+        if isinstance(payload, dict):
+            return payload
+        if isinstance(payload, bytes):
+            payload = payload.decode("utf-8")
+        if isinstance(payload, str):
+            try:
+                parsed = json.loads(payload)
+            except json.JSONDecodeError as exc:
+                raise ValueError("WeChat API response is not valid JSON.") from exc
+            if isinstance(parsed, dict):
+                return parsed
+    raise ValueError("WeChat API response has an unsupported format.")
+
+
 def _default_expires_at():
     minutes = int(getattr(settings, "PAYMENT_QR_EXPIRES_MINUTES", 10) or 10)
     return timezone.now() + timedelta(minutes=minutes)
@@ -198,7 +217,7 @@ def _create_mock_payment_order(order: RechargeOrder) -> PaymentOrderCode:
 
 def _create_wechat_payment_order_with_sdk(order: RechargeOrder) -> PaymentOrderCode:
     try:
-        from wechatpayv3 import WeChatPay  # type: ignore
+        from wechatpayv3 import WeChatPay, WeChatPayType  # type: ignore
     except ImportError as exc:
         raise PaymentOrderCreateError("wechatpayv3 is not installed.") from exc
 
@@ -231,11 +250,16 @@ def _create_wechat_payment_order_with_sdk(order: RechargeOrder) -> PaymentOrderC
                 "total": _wechat_amount_cents(order.amount_money),
                 "currency": order.currency,
             },
+            pay_type=WeChatPayType.NATIVE,
         )
     except Exception as exc:  # pragma: no cover - depends on merchant SDK/runtime.
         raise PaymentOrderCreateError("WeChat native order creation failed.") from exc
 
-    code_url = response.get("code_url") if isinstance(response, dict) else None
+    try:
+        payload = _wechat_response_payload(response)
+    except ValueError as exc:
+        raise PaymentOrderCreateError("WeChat native order response was invalid.") from exc
+    code_url = payload.get("code_url")
     if not code_url:
         raise PaymentOrderCreateError("WeChat native order did not return code_url.")
     return PaymentOrderCode(code_url=str(code_url), expires_at=_default_expires_at())
@@ -398,7 +422,7 @@ def _query_wechat_payment_order_with_sdk(order: RechargeOrder) -> RechargePaymen
             "WeChat active payment query SDK binding is not configured."
         )
     try:
-        resource = query(out_trade_no=order.order_no)
+        resource = _wechat_response_payload(query(out_trade_no=order.order_no))
     except Exception as exc:  # pragma: no cover - depends on merchant SDK/runtime.
         raise PaymentQueryUnavailableError("WeChat trade query failed.") from exc
     if resource.get("trade_state") != "SUCCESS":

apps/billing/tests.py

@@ -1,8 +1,12 @@
 import threading
 import time
 import uuid
+import sys
+import tempfile
 from datetime import timedelta
 from decimal import Decimal
+from types import SimpleNamespace
+from unittest.mock import patch
 
 from cryptography.fernet import Fernet
 from django.contrib import admin
@@ -28,6 +32,7 @@ from apps.billing.pricing import (
     get_pricing_rule,
     quote_recharge_points,
 )
+from apps.billing import payment_gateways
 from apps.billing.payment_gateways import PaymentOrderCode
 from apps.billing.services import (
     InsufficientPointsError,
@@ -497,6 +502,97 @@ class BillingServiceTests(TestCase):
         self.assertEqual(order.status, RechargeOrder.Status.FAILED)
         self.assertEqual(order.code_url, "")
 
+    def test_wechat_sdk_native_order_passes_explicit_pay_type(self):
+        order = self.create_recharge_order(amount="1.00", points_granted=10)
+
+        class FakeWeChatPayType:
+            NATIVE = object()
+
+        class FakeWeChatPay:
+            pay_kwargs = None
+
+            def __init__(self, **_kwargs):
+                pass
+
+            def pay(self, **kwargs):
+                FakeWeChatPay.pay_kwargs = kwargs
+                return (
+                    200,
+                    '{"code_url":"weixin://wxpay/bizpayurl?pr=test-ticket"}',
+                )
+
+        fake_module = SimpleNamespace(
+            WeChatPay=FakeWeChatPay,
+            WeChatPayType=FakeWeChatPayType,
+        )
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            private_key_path = f"{tmpdir}/apiclient_key.pem"
+            with open(private_key_path, "w", encoding="utf-8") as private_key:
+                private_key.write("test-private-key")
+
+            with (
+                patch.dict(sys.modules, {"wechatpayv3": fake_module}),
+                override_settings(
+                    WECHAT_PAY_APPID="wx-test-appid",
+                    WECHAT_PAY_MCHID="1900000001",
+                    WECHAT_PAY_API_V3_KEY="a" * 32,
+                    WECHAT_PAY_CERT_SERIAL_NO="ABC123",
+                    WECHAT_PAY_PRIVATE_KEY_PATH=private_key_path,
+                    WECHAT_PAY_NOTIFY_URL="https://cm.example.test/api/v1/recharge/callback/wechat",
+                ),
+            ):
+                payment_order = payment_gateways._create_wechat_payment_order_with_sdk(order)
+
+        self.assertEqual(
+            payment_order.code_url,
+            "weixin://wxpay/bizpayurl?pr=test-ticket",
+        )
+        self.assertIs(FakeWeChatPay.pay_kwargs["pay_type"], FakeWeChatPayType.NATIVE)
+
+    def test_wechat_sdk_query_parses_tuple_json_response(self):
+        order = self.create_recharge_order(amount="1.00", points_granted=10)
+
+        class FakeWeChatPay:
+            def __init__(self, **_kwargs):
+                pass
+
+            def query(self, **_kwargs):
+                return (
+                    200,
+                    (
+                        '{"trade_state":"SUCCESS",'
+                        f'"out_trade_no":"{order.order_no}",'
+                        '"amount":{"total":100},'
+                        '"transaction_id":"wx-transaction-001",'
+                        '"success_time":"2026-07-04T17:40:00+08:00"}'
+                    ),
+                )
+
+        fake_module = SimpleNamespace(WeChatPay=FakeWeChatPay)
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            private_key_path = f"{tmpdir}/apiclient_key.pem"
+            with open(private_key_path, "w", encoding="utf-8") as private_key:
+                private_key.write("test-private-key")
+
+            with (
+                patch.dict(sys.modules, {"wechatpayv3": fake_module}),
+                override_settings(
+                    WECHAT_PAY_APPID="wx-test-appid",
+                    WECHAT_PAY_MCHID="1900000001",
+                    WECHAT_PAY_API_V3_KEY="a" * 32,
+                    WECHAT_PAY_CERT_SERIAL_NO="ABC123",
+                    WECHAT_PAY_PRIVATE_KEY_PATH=private_key_path,
+                    WECHAT_PAY_NOTIFY_URL="https://cm.example.test/api/v1/recharge/callback/wechat",
+                ),
+            ):
+                payment = payment_gateways._query_wechat_payment_order_with_sdk(order)
+
+        self.assertEqual(payment.order_no, order.order_no)
+        self.assertEqual(payment.amount, Decimal("1.00"))
+        self.assertEqual(payment.transaction_id, "wx-transaction-001")
+
     def test_precharge_call_debits_wallet_and_writes_pending_call_and_consume_ledger(self):
         charge = precharge_call(
             user=self.user,