Pass 2

tests/test_migrations/conftest.py

@@ -2,4 +2,4 @@
 # run ``run_migrations`` to completion assert ``get_version == LATEST`` and
 # ``applied == LATEST - starting_version`` so only this constant needs to
 # change, not every individual assertion.
-LATEST_SCHEMA_VERSION = 57
+LATEST_SCHEMA_VERSION = 58

tests/test_push_send.py

@@ -0,0 +1,74 @@
+"""Tests for Web Push delivery transport behavior."""
+
+from types import SimpleNamespace
+from unittest.mock import patch
+
+import pytest
+import requests
+
+from app.push.send import (
+    DEFAULT_PUSH_CONNECT_TIMEOUT_SECONDS,
+    DEFAULT_PUSH_READ_TIMEOUT_SECONDS,
+    IPV4_FALLBACK_CONNECT_TIMEOUT_SECONDS,
+    IPv4HTTPAdapter,
+    send_push,
+)
+
+
+@pytest.mark.asyncio
+async def test_send_push_prefers_default_dual_stack_session_before_any_ipv4_fallback():
+    """Successful sends should use the normal requests transport without forcing IPv4."""
+    captured_kwargs: dict = {}
+
+    def fake_webpush(**kwargs):
+        captured_kwargs.update(kwargs)
+        return SimpleNamespace(status_code=201)
+
+    with patch("app.push.send.webpush", side_effect=fake_webpush):
+        status = await send_push(
+            subscription_info={"endpoint": "https://push.example.test", "keys": {}},
+            payload='{"message":"hello"}',
+            vapid_private_key="private-key",
+            vapid_claims={"sub": "mailto:test@example.com"},
+        )
+
+    assert status == 201
+    session = captured_kwargs["requests_session"]
+    assert not isinstance(session.adapters["https://"], IPv4HTTPAdapter)
+    assert captured_kwargs["timeout"] == (
+        DEFAULT_PUSH_CONNECT_TIMEOUT_SECONDS,
+        DEFAULT_PUSH_READ_TIMEOUT_SECONDS,
+    )
+
+
+@pytest.mark.asyncio
+async def test_send_push_retries_with_ipv4_session_after_connect_timeout():
+    """Connect failures should retry through the isolated IPv4-only transport."""
+    calls: list[dict] = []
+
+    def fake_webpush(**kwargs):
+        calls.append(kwargs)
+        if len(calls) == 1:
+            raise requests.exceptions.ConnectTimeout("ipv6 connect timed out")
+        return SimpleNamespace(status_code=201)
+
+    with patch("app.push.send.webpush", side_effect=fake_webpush):
+        status = await send_push(
+            subscription_info={"endpoint": "https://push.example.test", "keys": {}},
+            payload='{"message":"hello"}',
+            vapid_private_key="private-key",
+            vapid_claims={"sub": "mailto:test@example.com"},
+        )
+
+    assert status == 201
+    assert len(calls) == 2
+    assert not isinstance(calls[0]["requests_session"].adapters["https://"], IPv4HTTPAdapter)
+    assert isinstance(calls[1]["requests_session"].adapters["https://"], IPv4HTTPAdapter)
+    assert calls[0]["timeout"] == (
+        DEFAULT_PUSH_CONNECT_TIMEOUT_SECONDS,
+        DEFAULT_PUSH_READ_TIMEOUT_SECONDS,
+    )
+    assert calls[1]["timeout"] == (
+        IPV4_FALLBACK_CONNECT_TIMEOUT_SECONDS,
+        DEFAULT_PUSH_READ_TIMEOUT_SECONDS,
+    )