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我一直在尝试使用 typescript 实现 Apollo 的新网关。但是我一直遇到一个我似乎无法解决的打字稿问题。错误消息是“类型 'TContext'.ts(2339) 上不存在属性 'userId'”。注意我正在尝试在 AWS Lambda 上实施。

据我所知，通过查看包源代码 TContext = Record 是一个对象，但它似乎没有解决。

import { ApolloServer } from 'apollo-server-lambda';
import { ApolloGateway, RemoteGraphQLDataSource } from '@apollo/gateway';


const gateway = new ApolloGateway({
  serviceList: [
    { name: 'users', url: 'xx' },
    { name: 'precedents', url: 'xx' }
    // other services
  ],
  buildService({ url }) {
    return new RemoteGraphQLDataSource({
      url,
      willSendRequest({ request, context }) {
        // pass the user's id from the context to underlying services
        // as a header called `user-id`
        request && request.http && request.http.headers.set('user-id', context.userId);
      }
    });
  }
});

const server = new ApolloServer({
  gateway,
  subscriptions: false,
  context: ({ event, context }) => {
    // get the user token from the headers
    const token = event.headers.authorization || '';

    // try to retrieve a user with the token
    const userId = token;

    // add the user to the context
    return {
      headers: event.headers,
      functionName: context.functionName,
      event,
      context,
      userId
    };
  }
});

exports.handler = server.createHandler({
  cors: {
    origin: true,
    credentials: true,
    methods: ['POST', 'GET'],
    allowedHeaders: ['Content-Type', 'Origin', 'Accept', 'authorization']
  }
});

下面的编辑 更新似乎会导致同样的问题。

interface MyContext{
    userId: string;
}

const gateway = new ApolloGateway({
  serviceList: [
    { name: 'users', url: 'xx' },
    { name: 'precedents', url: 'xx' }
    // other services
  ],
  buildService({ url }) {
    return new RemoteGraphQLDataSource({
      url,
      willSendRequest<MyContext>({ request, context } : {request: GraphQLRequest, context: MyContext}) {
        // pass the user's id from the context to underlying services
        // as a header called `user-id`
        request && request.http && request.http.headers.set('user-id', context.userID);
      }
    });
  }
});
4

1 回答 1

0

首先，创建一个接口，它将描述您的 graphql 上下文

interface MyContext{
    userId: string;
}

然后像这样将 MyContext 类型参数添加到 willSendRequest 方法

...
willSendRequest<MyContext>({request, context}) {
...

现在编译器知道，上下文是 MyContext 类型的。

于 2019-09-13T11:28:36.450 回答