test: automatically count queries in webtest (#19544)

* test: automatically count queries in webtest

Signed-off-by: Mike Fiedler <miketheman@gmail.com>

* test: add functional test for JSON API

Signed-off-by: Mike Fiedler <miketheman@gmail.com>

---------

Signed-off-by: Mike Fiedler <miketheman@gmail.com>

Author: miketheman

tests/conftest.py

@@ -697,6 +697,23 @@ def _make_email_renderers(
 
 
 class _TestApp(_webtest.TestApp):
+    def __init__(self, app, engine, **kwargs):
+        super().__init__(app, **kwargs)
+        self._engine = engine
+        self.query_recorder = QueryRecorder()
+        event.listen(self._engine, "before_cursor_execute", self.query_recorder.record)
+
+    def do_request(self, *args, **kwargs):
+        self.query_recorder.clear()
+        self.query_recorder.start()
+        try:
+            return super().do_request(*args, **kwargs)
+        finally:
+            self.query_recorder.stop()
+
+    def close(self):
+        event.remove(self._engine, "before_cursor_execute", self.query_recorder.record)
+
     def xmlrpc(self, path, method, *args):
         body = xmlrpc.client.dumps(args, methodname=method)
         resp = self.post(path, body, headers={"Content-Type": "text/xml"})
@@ -731,12 +748,14 @@ def webtest(app_config_dbsession_from_env, tm):
     app_config_dbsession_from_env.add_settings(enforce_https=False)
 
     app = app_config_dbsession_from_env.make_wsgi_app()
+    engine = app_config_dbsession_from_env.registry["sqlalchemy.engine"]
 
     with get_db_session_for_app_config(app_config_dbsession_from_env) as _db_session:
         # Register the app with the external test environment, telling
         # request.db to use this db_session and use the Transaction manager.
         testapp = _TestApp(
             app,
+            engine,
             extra_environ={
                 "warehouse.db_session": _db_session,
                 "tm.active": True,  # disable pyramid_tm
@@ -745,6 +764,7 @@ def webtest(app_config_dbsession_from_env, tm):
             },
         )
         yield testapp
+        testapp.close()
 
 
 class _MockRedis:

tests/functional/legacy/api/test_json.py

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: Apache-2.0
+
+from tests.common.db.packaging import ReleaseFactory
+
+
+def test_json_project(webtest):
+    """
+    Testing JSON API for basic structure
+
+    Exercises `warehouse.legacy.api.json.json_project` with full web stack
+    """
+    release = ReleaseFactory.create()
+
+    resp = webtest.get(f"/pypi/{release.project.normalized_name}/json")
+
+    assert resp.status_code == 200
+    assert resp.headers["Cache-Control"] == "max-age=900, public"
+    assert resp.headers["Content-Type"] == "application/json"
+    assert resp.headers["X-PyPI-Last-Serial"] == str(release.project.last_serial)
+    # How many database calls are needed to satisfy the data
+    assert len(webtest.query_recorder.queries) == 7