fix: handle AttributeError in bigquery_storage writer (#414)

* fix: resolve AttributeError in bigquery_storage writer

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* handle AttributeError to avoid race condition

* actually catch AttributeError

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Steffany Brown <30247553+steffnay@users.noreply.github.com>

google/cloud/bigquery_storage_v1/writer.py

@@ -182,21 +182,35 @@ def _open(
         # ValueError: Can not send() on an RPC that has never been open()ed.
         #
         # when they try to send a request.
-        while not self._rpc.is_active and self._consumer.is_active:
-            # Avoid 100% CPU while waiting for RPC to be ready.
-            time.sleep(_WRITE_OPEN_INTERVAL)
-
-            # TODO: Check retry.deadline instead of (per-request) timeout.
-            # Blocked by
-            # https://github.com/googleapis/python-api-core/issues/262
-            if timeout is None:
-                continue
-            current_time = time.monotonic()
-            if current_time - start_time > timeout:
-                break
+        try:
+            while not self._rpc.is_active and self._consumer.is_active:
+                # Avoid 100% CPU while waiting for RPC to be ready.
+                time.sleep(_WRITE_OPEN_INTERVAL)
+
+                # TODO: Check retry.deadline instead of (per-request) timeout.
+                # Blocked by
+                # https://github.com/googleapis/python-api-core/issues/262
+                if timeout is None:
+                    continue
+                current_time = time.monotonic()
+                if current_time - start_time > timeout:
+                    break
+        except AttributeError:
+            # Handle the AttributeError which can occur if the stream is
+            # unable to be opened. In that case, self._rpc or self._consumer
+            # may be None.
+            pass
+
+        try:
+            is_consumer_active = self._consumer.is_active
+        except AttributeError:
+            # Handle the AttributeError which can occur if the stream is
+            # unable to be opened. In that case, self._consumer
+            # may be None.
+            is_consumer_active = False
 
         # Something went wrong when opening the RPC.
-        if not self._consumer.is_active:
+        if not is_consumer_active:
             # TODO: Share the exception from _rpc.open(). Blocked by
             # https://github.com/googleapis/python-api-core/issues/268
             request_exception = exceptions.Unknown(

google/cloud/bigquery_storage_v1beta2/writer.py

@@ -182,21 +182,35 @@ def _open(
         # ValueError: Can not send() on an RPC that has never been open()ed.
         #
         # when they try to send a request.
-        while not self._rpc.is_active and self._consumer.is_active:
-            # Avoid 100% CPU while waiting for RPC to be ready.
-            time.sleep(_WRITE_OPEN_INTERVAL)
-
-            # TODO: Check retry.deadline instead of (per-request) timeout.
-            # Blocked by
-            # https://github.com/googleapis/python-api-core/issues/262
-            if timeout is None:
-                continue
-            current_time = time.monotonic()
-            if current_time - start_time > timeout:
-                break
+        try:
+            while not self._rpc.is_active and self._consumer.is_active:
+                # Avoid 100% CPU while waiting for RPC to be ready.
+                time.sleep(_WRITE_OPEN_INTERVAL)
+
+                # TODO: Check retry.deadline instead of (per-request) timeout.
+                # Blocked by
+                # https://github.com/googleapis/python-api-core/issues/262
+                if timeout is None:
+                    continue
+                current_time = time.monotonic()
+                if current_time - start_time > timeout:
+                    break
+        except AttributeError:
+            # Handle the AttributeError which can occur if the stream is
+            # unable to be opened. In that case, self._rpc or self._consumer
+            # may be None.
+            pass
+
+        try:
+            is_consumer_active = self._consumer.is_active
+        except AttributeError:
+            # Handle the AttributeError which can occur if the stream is
+            # unable to be opened. In that case, self._consumer
+            # may be None.
+            is_consumer_active = False
 
         # Something went wrong when opening the RPC.
-        if not self._consumer.is_active:
+        if not is_consumer_active:
             # TODO: Share the exception from _rpc.open(). Blocked by
             # https://github.com/googleapis/python-api-core/issues/268
             request_exception = exceptions.Unknown(