bigquery_client.py•1.26 kB
"""BigQuery client helper for MCP server."""
import os
from google.auth.exceptions import DefaultCredentialsError
from google.cloud import bigquery
def get_bigquery_client() -> bigquery.Client:
"""
Create and return a configured BigQuery client.
Uses Application Default Credentials (ADC) by default.
Respects environment variables:
- BQ_PROJECT: GCP project ID
- BQ_LOCATION: Default location for BigQuery operations
Returns:
bigquery.Client: Configured BigQuery client
Raises:
DefaultCredentialsError: If credentials cannot be found
"""
project = os.environ.get("BQ_PROJECT")
location = os.environ.get("BQ_LOCATION")
try:
# Create client with location if provided
if location:
client = bigquery.Client(project=project, location=location)
else:
client = bigquery.Client(project=project)
return client
except DefaultCredentialsError as e:
raise DefaultCredentialsError(
"No BigQuery credentials found. Please set up Application "
"Default Credentials or provide a service account key. "
"Run 'gcloud auth application-default login' for local "
"development."
) from e