mirror of
https://github.com/hwchase17/langchain
synced 2024-11-10 01:10:59 +00:00
55 lines
1.9 KiB
Python
55 lines
1.9 KiB
Python
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import json
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from typing import Any, Callable, Dict, Optional
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from langchain_core.pydantic_v1 import BaseModel, Extra, root_validator
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class GraphQLAPIWrapper(BaseModel):
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"""Wrapper around GraphQL API.
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To use, you should have the ``gql`` python package installed.
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This wrapper will use the GraphQL API to conduct queries.
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"""
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custom_headers: Optional[Dict[str, str]] = None
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graphql_endpoint: str
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gql_client: Any #: :meta private:
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gql_function: Callable[[str], Any] #: :meta private:
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class Config:
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"""Configuration for this pydantic object."""
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extra = Extra.forbid
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@root_validator(pre=True)
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def validate_environment(cls, values: Dict) -> Dict:
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"""Validate that the python package exists in the environment."""
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try:
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from gql import Client, gql
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from gql.transport.requests import RequestsHTTPTransport
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except ImportError as e:
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raise ImportError(
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"Could not import gql python package. "
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f"Try installing it with `pip install gql`. Received error: {e}"
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)
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headers = values.get("custom_headers")
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transport = RequestsHTTPTransport(
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url=values["graphql_endpoint"],
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headers=headers,
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)
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client = Client(transport=transport, fetch_schema_from_transport=True)
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values["gql_client"] = client
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values["gql_function"] = gql
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return values
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def run(self, query: str) -> str:
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"""Run a GraphQL query and get the results."""
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result = self._execute_query(query)
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return json.dumps(result, indent=2)
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def _execute_query(self, query: str) -> Dict[str, Any]:
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"""Execute a GraphQL query and return the results."""
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document_node = self.gql_function(query)
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result = self.gql_client.execute(document_node)
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return result
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