Source code for langchain_community.document_loaders.bigquery

from __future__ import annotations

from typing import TYPE_CHECKING, List, Optional

from langchain_core._api.deprecation import deprecated
from langchain_core.documents import Document

from langchain_community.document_loaders.base import BaseLoader
from langchain_community.utilities.vertexai import get_client_info

    from google.auth.credentials import Credentials

[docs]@deprecated( since="0.0.32", removal="0.3.0", alternative_import="langchain_google_community.BigQueryLoader", ) class BigQueryLoader(BaseLoader): """Load from the Google Cloud Platform `BigQuery`. Each document represents one row of the result. The `page_content_columns` are written into the `page_content` of the document. The `metadata_columns` are written into the `metadata` of the document. By default, all columns are written into the `page_content` and none into the `metadata`. """
[docs] def __init__( self, query: str, project: Optional[str] = None, page_content_columns: Optional[List[str]] = None, metadata_columns: Optional[List[str]] = None, credentials: Optional[Credentials] = None, ): """Initialize BigQuery document loader. Args: query: The query to run in BigQuery. project: Optional. The project to run the query in. page_content_columns: Optional. The columns to write into the `page_content` of the document. metadata_columns: Optional. The columns to write into the `metadata` of the document. credentials : google.auth.credentials.Credentials, optional Credentials for accessing Google APIs. Use this parameter to override default credentials, such as to use Compute Engine (`google.auth.compute_engine.Credentials`) or Service Account (`google.oauth2.service_account.Credentials`) credentials directly. """ self.query = query self.project = project self.page_content_columns = page_content_columns self.metadata_columns = metadata_columns self.credentials = credentials
[docs] def load(self) -> List[Document]: try: from import bigquery except ImportError as ex: raise ImportError( "Could not import google-cloud-bigquery python package. " "Please install it with `pip install google-cloud-bigquery`." ) from ex bq_client = bigquery.Client( credentials=self.credentials, project=self.project, client_info=get_client_info(module="bigquery"), ) if not bq_client.project: error_desc = ( "GCP project for Big Query is not set! Either provide a " "`project` argument during BigQueryLoader instantiation, " "or set a default project with `gcloud config set project` " "command." ) raise ValueError(error_desc) query_result = bq_client.query(self.query).result() docs: List[Document] = [] page_content_columns = self.page_content_columns metadata_columns = self.metadata_columns if page_content_columns is None: page_content_columns = [ for column in query_result.schema] if metadata_columns is None: metadata_columns = [] for row in query_result: page_content = "\n".join( f"{k}: {v}" for k, v in row.items() if k in page_content_columns ) metadata = {k: v for k, v in row.items() if k in metadata_columns} doc = Document(page_content=page_content, metadata=metadata) docs.append(doc) return docs