feat: Multi db test parametrization (#717)

* feat: Multi db test parametrization

The changes are:

- adding test parametrization wherever the client is used. It will run the test against the default db, and a named db
named db can only be passed to the Client, and the underlying queries and aggregation queries will retrieve the database id from the Client.

* Fix unit test import

* Fix unit test import

* fix: change non-default database name

* fix: added client test without any database set

---------

Co-authored-by: Vishwaraj Anand <vishwaraj.anand00@gmail.com>
Co-authored-by: kolea2 <45548808+kolea2@users.noreply.github.com>
Co-authored-by: Anthonios Partheniou <partheniou@google.com>

google/cloud/firestore_v1/async_client.py

@@ -29,7 +29,6 @@
 
 from google.cloud.firestore_v1.base_client import (
     BaseClient,
-    DEFAULT_DATABASE,
     _CLIENT_INFO,
     _parse_batch_get,  # type: ignore
     _path_helper,
@@ -88,7 +87,7 @@ def __init__(
         self,
         project=None,
         credentials=None,
-        database=DEFAULT_DATABASE,
+        database=None,
         client_info=_CLIENT_INFO,
         client_options=None,
     ) -> None:

google/cloud/firestore_v1/base_client.py

@@ -117,10 +117,11 @@ def __init__(
         self,
         project=None,
         credentials=None,
-        database=DEFAULT_DATABASE,
+        database=None,
         client_info=_CLIENT_INFO,
         client_options=None,
     ) -> None:
+        database = database or DEFAULT_DATABASE
         # NOTE: This API has no use for the _http argument, but sending it
         #       will have no impact since the _http() @property only lazily
         #       creates a working HTTP object.

google/cloud/firestore_v1/client.py

@@ -29,7 +29,6 @@
 
 from google.cloud.firestore_v1.base_client import (
     BaseClient,
-    DEFAULT_DATABASE,
     _CLIENT_INFO,
     _parse_batch_get,
     _path_helper,
@@ -86,7 +85,7 @@ def __init__(
         self,
         project=None,
         credentials=None,
-        database=DEFAULT_DATABASE,
+        database=None,
         client_info=_CLIENT_INFO,
         client_options=None,
     ) -> None:

tests/system/test__helpers.py

@@ -12,3 +12,4 @@
 UNIQUE_RESOURCE_ID = unique_resource_id("-")
 EMULATOR_CREDS = EmulatorCreds()
 FIRESTORE_EMULATOR = os.environ.get(_FIRESTORE_EMULATOR_HOST) is not None
+FIRESTORE_OTHER_DB = os.environ.get("SYSTEM_TESTS_DATABASE", "system-tests-named-db")