GraphQL
GraphQL 是一种用于 API 的查询语言，以及执行这些查询以访问数据的运行时。
GraphQL提供了 API 中数据的完整且易于理解的描述，使客户端能够精确请求所需的内容，而不是多余的内容，简化了 API 随时间的演变，并支持强大的开发者工具。
通过在提供给代理的工具列表中包含 BaseGraphQLTool，您可以赋予代理从 GraphQL API 查询数据的能力，以满足您所需的任何目的。
此 Jupyter Notebook 演示了如何使用 GraphQLAPIWrapper 组件与代理。
在此示例中，我们将使用可在以下端点访问的公共 Star Wars GraphQL API： https://swapi-graphql.netlify.app/.netlify/functions/index。
首先，您需要安装 httpx 和 gql Python 包。
pip install httpx gql > /dev/null
%pip install --upgrade --quiet langchain-community
现在，让我们创建一个带有指定星球大战 API 端点的 BaseGraphQLTool 实例，并用该工具初始化一个代理。
from langchain.agents import AgentType, initialize_agent, load_tools
from langchain_openai import OpenAI
llm = OpenAI(temperature=0)
tools = load_tools(
["graphql"],
graphql_endpoint="https://swapi-graphql.netlify.app/.netlify/functions/index",
)
agent = initialize_agent(
tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True
)
现在，我们可以使用代理对星球大战 GraphQL API 运行查询。让我们请求代理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 "
agent.run(suffix + graphql_fields)
[1m> Entering new AgentExecutor chain...[0m
[32;1m[1;3m I need to query the graphql database to get the titles of all the star wars films
Action: query_graphql
Action Input: query { allFilms { films { title } } }[0m
Observation: [36;1m[1;3m"{\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}"[0m
Thought:[32;1m[1;3m I now know the titles of all the star wars films
Final Answer: The titles of all the star wars films are: A New Hope, The Empire Strikes Back, Return of the Jedi, The Phantom Menace, Attack of the Clones, and Revenge of the Sith.[0m
[1m> Finished chain.[0m
'The titles of all the star wars films are: A New Hope, The Empire Strikes Back, Return of the Jedi, The Phantom Menace, Attack of the Clones, and Revenge of the Sith.'