rewrites drivers

tests/test_orm.py

@@ -0,0 +1,52 @@
+import pytest
+
+from yhttp.ext.sqlalchemy.orm import ORM
+
+
+def _engine_url(monkeypatch, url):
+    seen = {}
+
+    def fake_create_engine(target, **kwargs):
+        seen['url'] = target
+        seen['kwargs'] = kwargs
+
+        class Engine:
+            def dispose(self):
+                return None
+
+        return Engine()
+
+    monkeypatch.setattr(
+        'yhttp.ext.sqlalchemy.orm.create_engine',
+        fake_create_engine,
+    )
+    orm = ORM(object())
+    orm.connect(url)
+    try:
+        return seen
+    finally:
+        orm.disconnect()
+
+
+@pytest.mark.parametrize('url', (
+    'postgresql://user:pass@localhost:5432/dbname?sslmode=require',
+    'postgres://user:pass@localhost:5432/dbname?sslmode=require',
+))
+def test_driverless_postgresql_uses_psycopg2(monkeypatch, url):
+    seen = _engine_url(monkeypatch, url)
+    parsed = seen['url']
+
+    assert parsed.drivername == 'postgresql+psycopg2'
+
+
+@pytest.mark.parametrize('url', (
+    'postgresql+psycopg2://user:pass@localhost/dbname',
+    'postgresql+psycopg://user:pass@localhost/dbname',
+    'postgresql+asyncpg://user:pass@localhost/dbname',
+))
+def test_explicit_postgresql_driver_unchanged(monkeypatch, url):
+    seen = _engine_url(monkeypatch, url)
+
+    assert seen['url'].drivername == url.split(':', 1)[0]
+    assert seen['url'].username == 'user'
+    assert seen['url'].database == 'dbname'

yhttp/ext/sqlalchemy/__init__.py

@@ -1,4 +1,4 @@
 from .install import install
 
 
-__version__ = '6.1.0'
+__version__ = '6.1.1'

yhttp/ext/sqlalchemy/orm.py

@@ -1,4 +1,5 @@
 from sqlalchemy import create_engine
+from sqlalchemy.engine import make_url
 from sqlalchemy.orm import sessionmaker, close_all_sessions, Session, \
     scoped_session
 
@@ -22,8 +23,14 @@ def connect(self, url=None):
         assert self.engine is None
         assert u is not None
 
+        parsed = make_url(u)
+        if parsed.drivername in ('postgresql', 'postgres'):
+            # SQLAlchemy 2.1 loads psycopg 3 for a driverless URL.
+            # https://docs.sqlalchemy.org/en/21/changelog/migration_21.html#default-postgresql-driver-changed-to-psycopg-psycopg-3  # noqa: E501
+            parsed = parsed.set(drivername='postgresql+psycopg2')
+
         self.engine = create_engine(
-            u,
+            parsed,
             isolation_level='REPEATABLE READ',
             plugins=self.saplugins or [],
         )