跳到主要内容
Open In ColabOpen on GitHub

GraphQL

GraphQL 是一种用于 API 的查询语言，也是一个针对您的数据执行这些查询的运行时。GraphQL 提供了 API 中数据的完整且易于理解的描述，使客户端能够精确地请求所需数据，不多不少，使得 API 随时间演进变得更容易，并支持强大的开发者工具。

通过在提供给 Agent 的工具列表中包含 BaseGraphQLTool，您可以赋予您的 Agent 从 GraphQL API 查询数据的能力，以满足您的任何需求。

本 Jupyter Notebook 演示了如何将 GraphQLAPIWrapper 组件与 Agent 结合使用。

在本示例中，我们将使用以下公共 星球大战 GraphQL API 端点： https://swapi-graphql.netlify.app/graphql。

首先，您需要安装 httpx 和 gql 这两个 Python 包。

pip install httpx gql > /dev/null
Note: you may need to restart the kernel to use updated packages.
%pip install --upgrade --quiet  langchain-community
Note: you may need to restart the kernel to use updated packages.

现在，让我们使用指定的星球大战 API 端点创建一个 BaseGraphQLTool 实例，并用该工具初始化一个 Agent。

import os

os.environ["OPENAI_API_KEY"] = ""
from langchain_community.agent_toolkits.load_tools import load_tools

tools = load_tools(
    ["graphql"],
    graphql_endpoint="https://swapi-graphql.netlify.app/graphql",
)
API 参考：load_tools
from langgraph.prebuilt import create_react_agent

agent = create_react_agent("openai:gpt-4.1-mini", tools)
API 参考：create_react_agent

现在，我们可以使用 Agent 对星球大战 GraphQL API 运行查询。让我们让 Agent 列出所有星球大战电影及其上映日期。

graphql_fields = """allFilms {
    films {
      title
      director
      releaseDate
      speciesConnection {
        species {
          name
          classification
          homeworld {
            name
          }
        }
      }
    }
  }

"""

suffix = "Search for the titles of all the stawars films stored in the graphql database that has this schema "

input_message = {
    "role": "user",
    "content": suffix + graphql_fields,
}

for step in agent.stream(
    {"messages": [input_message]},
    stream_mode="values",
):
    step["messages"][-1].pretty_print()
================================ Human Message =================================

Search for the titles of all the stawars films stored in the graphql database that has this schema allFilms {
    films {
      title
      director
      releaseDate
      speciesConnection {
        species {
          name
          classification
          homeworld {
            name
          }
        }
      }
    }
  }


================================== Ai Message ==================================
Tool Calls:
  query_graphql (call_tN5A0dBbfOMewuw8Yy13bYpW)
 Call ID: call_tN5A0dBbfOMewuw8Yy13bYpW
  Args:
    tool_input: query { allFilms { films { title } } }
================================= Tool Message =================================
Name: query_graphql

"{\n  \"allFilms\": {\n    \"films\": [\n      {\n        \"title\": \"A New Hope\"\n      },\n      {\n        \"title\": \"The Empire Strikes Back\"\n      },\n      {\n        \"title\": \"Return of the Jedi\"\n      },\n      {\n        \"title\": \"The Phantom Menace\"\n      },\n      {\n        \"title\": \"Attack of the Clones\"\n      },\n      {\n        \"title\": \"Revenge of the Sith\"\n      }\n    ]\n  }\n}"
================================== Ai Message ==================================

The titles of all the Star Wars films stored in the database are:
1. A New Hope
2. The Empire Strikes Back
3. Return of the Jedi
4. The Phantom Menace
5. Attack of the Clones
6. Revenge of the Sith

If you would like more information about any of these films, please let me know!