Test retry of failed initial db connection (#1269)

Added tests

parsec/backend/postgresql/handler.py

@@ -195,6 +195,7 @@ async def _run_connections(self, task_status=trio.TASK_STATUS_IGNORED):
             except OSError:
                 postgres_initial_connect_failed = True
                 if self.first_tries_number == 1:
+                    logger.error("initial db connection failed", tries_remaining=0)
                     raise
                 if self.first_tries_number > 1:
                     self.first_tries_number -= 1

tests/backend/test_postgres_db.py

@@ -0,0 +1,59 @@
+# Parsec Cloud (https://parsec.cloud) Copyright (c) AGPLv3 2019 Scille SAS
+
+import pytest
+import trio
+
+
+def records_filter_debug(records):
+    return [record for record in records if record.levelname != "DEBUG"]
+
+
+@pytest.mark.trio
+@pytest.mark.postgresql
+async def test_postgresql_connection_ok(postgresql_url, backend_factory, blockstore):
+    async with backend_factory(config={"db_url": postgresql_url}):
+        pass
+
+
+@pytest.mark.trio
+@pytest.mark.postgresql
+async def test_postgresql_connection_not_ok(
+    postgresql_url, backend_factory, caplog, unused_tcp_port
+):
+    postgresql_url = f"postgresql://localhost:{unused_tcp_port}/dummy"
+    with pytest.raises(OSError) as exc:
+        async with backend_factory(config={"db_url": postgresql_url}):
+            pass
+    assert "[Errno 111] Connect call failed" in str(exc.value)
+    records = records_filter_debug(caplog.records)
+    assert len(records) == 1
+    assert records[0].levelname == "ERROR"
+    assert "initial db connection failed" in records[0].message
+
+
+@pytest.mark.trio
+@pytest.mark.postgresql
+async def test_postgresql_connection_not_ok_retrying(
+    postgresql_url, backend_factory, caplog, unused_tcp_port, autojump_clock
+):
+    tries_number = 4
+    tries_sleep = 3
+    postgresql_url = f"postgresql://localhost:{unused_tcp_port}/dummy"
+    with pytest.raises(OSError) as exc:
+        with trio.fail_after((tries_number - 1) * tries_sleep + 1):
+            async with backend_factory(
+                config={
+                    "db_url": postgresql_url,
+                    "db_first_tries_number": tries_number,
+                    "db_first_tries_sleep": tries_sleep,
+                }
+            ):
+                pass
+    assert "[Errno 111] Connect call failed" in str(exc.value)
+    records = records_filter_debug(caplog.records)
+    assert len(records) == 4
+    for record in records[:3]:
+        assert record.levelname == "WARNING"
+        assert "initial db connection failed" in record.message
+    assert records[3].levelname == "ERROR"
+    assert "initial db connection failed" in records[3].message