from typing import Iterator, Optional, Sequence from langchain_core.documents import Document from langchain_community.document_loaders.base import BaseLoader class FaunaLoader(BaseLoader): """Load from `FaunaDB`. Attributes: query (str): The FQL query string to execute. page_content_field (str): The field that contains the content of each page. secret (str): The secret key for authenticating to FaunaDB. metadata_fields (Optional[Sequence[str]]): Optional list of field names to include in metadata. """ def __init__( self, query: str, page_content_field: str, secret: str, metadata_fields: Optional[Sequence[str]] = None, ): self.query = query self.page_content_field = page_content_field self.secret = secret self.metadata_fields = metadata_fields def lazy_load(self) -> Iterator[Document]: try: from fauna import Page, fql from fauna.client import Client from fauna.encoding import QuerySuccess except ImportError: raise ImportError( "Could not import fauna python package. " "Please install it with `pip install fauna`." ) # Create Fauna Client client = Client(secret=self.secret) # Run FQL Query response: QuerySuccess = client.query(fql(self.query)) page: Page = response.data for result in page: if result is not None: document_dict = dict(result.items()) page_content = "" for key, value in document_dict.items(): if key == self.page_content_field: page_content = value document: Document = Document( page_content=page_content, metadata={"id": result.id, "ts": result.ts}, ) yield document if page.after is not None: yield Document( page_content="Next Page Exists", metadata={"after": page.after}, )