feat: Enable regional endpoints for me-central2 (#386)

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Fixes internal issue 312304785 🦕

bigframes/_config/bigquery_options.py

@@ -125,9 +125,8 @@ def use_regional_endpoints(self) -> bool:
         """Flag to connect to regional API endpoints.
 
         .. deprecated:: 0.13.0
-            BigQuery regional endpoints is a feature in preview and
-            available only to selected projects.
-            Enable it only if your project has regional endpoints access.
+            Use of regional endpoints is a feature in preview and
+            available only in selected regions and projects.
 
         Requires ``location`` to also be set. For example, set
         ``location='asia-northeast1'`` and ``use_regional_endpoints=True`` to
@@ -144,9 +143,8 @@ def use_regional_endpoints(self, value: bool):
 
         if value:
             warnings.warn(
-                "BigQuery regional endpoints is a feature in preview and "
-                "available only to selected projects. "
-                "Enable it only if your project has regional endpoints access."
+                "Use of regional endpoints is a feature in preview and "
+                "available only in selected regions and projects. "
             )
 
         self._use_regional_endpoints = value

bigframes/session/__init__.py

@@ -152,7 +152,7 @@ def __init__(
             context = bigquery_options.BigQueryOptions()
 
         # TODO(swast): Get location from the environment.
-        if context is None or context.location is None:
+        if context.location is None:
             self._location = "US"
             warnings.warn(
                 f"No explicit location is set, so using location {self._location} for the session.",

bigframes/session/clients.py

@@ -37,13 +37,21 @@
 _APPLICATION_NAME = f"bigframes/{bigframes.version.__version__} ibis/{ibis.__version__}"
 _SCOPES = ["https://www.googleapis.com/auth/cloud-platform"]
 
+# Regions for which Regional Endpoints (REPs) are supported
+_REP_SUPPORTED_REGIONS = {"me-central2"}
+
+
 # BigQuery is a REST API, which requires the protocol as part of the URL.
-_BIGQUERY_REGIONAL_ENDPOINT = "https://{location}-bigquery.googleapis.com"
+_BIGQUERY_LOCATIONAL_ENDPOINT = "https://{location}-bigquery.googleapis.com"
+_BIGQUERY_REGIONAL_ENDPOINT = "https://bigquery.{location}.rep.googleapis.com"
 
 # BigQuery Connection and Storage are gRPC APIs, which don't support the
 # https:// protocol in the API endpoint URL.
-_BIGQUERYCONNECTION_REGIONAL_ENDPOINT = "{location}-bigqueryconnection.googleapis.com"
-_BIGQUERYSTORAGE_REGIONAL_ENDPOINT = "{location}-bigquerystorage.googleapis.com"
+_BIGQUERYCONNECTION_LOCATIONAL_ENDPOINT = "{location}-bigqueryconnection.googleapis.com"
+_BIGQUERYSTORAGE_LOCATIONAL_ENDPOINT = "{location}-bigquerystorage.googleapis.com"
+_BIGQUERYSTORAGE_REGIONAL_ENDPOINT = (
+    "https://bigquerystorage.{location}.rep.googleapis.com"
+)
 
 
 def _get_default_credentials_with_project():
@@ -104,9 +112,11 @@ def bqclient(self):
             bq_options = None
             if self._use_regional_endpoints:
                 bq_options = google.api_core.client_options.ClientOptions(
-                    api_endpoint=_BIGQUERY_REGIONAL_ENDPOINT.format(
-                        location=self._location
-                    ),
+                    api_endpoint=(
+                        _BIGQUERY_REGIONAL_ENDPOINT
+                        if self._location.lower() in _REP_SUPPORTED_REGIONS
+                        else _BIGQUERY_LOCATIONAL_ENDPOINT
+                    ).format(location=self._location),
                 )
             bq_info = google.api_core.client_info.ClientInfo(
                 user_agent=self._application_name
@@ -127,7 +137,7 @@ def bqconnectionclient(self):
             bqconnection_options = None
             if self._use_regional_endpoints:
                 bqconnection_options = google.api_core.client_options.ClientOptions(
-                    api_endpoint=_BIGQUERYCONNECTION_REGIONAL_ENDPOINT.format(
+                    api_endpoint=_BIGQUERYCONNECTION_LOCATIONAL_ENDPOINT.format(
                         location=self._location
                     )
                 )
@@ -150,9 +160,11 @@ def bqstoragereadclient(self):
             bqstorage_options = None
             if self._use_regional_endpoints:
                 bqstorage_options = google.api_core.client_options.ClientOptions(
-                    api_endpoint=_BIGQUERYSTORAGE_REGIONAL_ENDPOINT.format(
-                        location=self._location
-                    )
+                    api_endpoint=(
+                        _BIGQUERYSTORAGE_REGIONAL_ENDPOINT
+                        if self._location.lower() in _REP_SUPPORTED_REGIONS
+                        else _BIGQUERYSTORAGE_LOCATIONAL_ENDPOINT
+                    ).format(location=self._location),
                 )
             bqstorage_info = google.api_core.gapic_v1.client_info.ClientInfo(
                 user_agent=self._application_name