如何在 GraphQL 中设置 http 状态码

Question

I want to set an http status code in my GraphQL authentication query, depending on if auth attempt was successful (200), unauthorised (401) or missing parameters (422).

I am using Koa and Apollo and have configured my server like so:

const graphqlKoaMiddleware = graphqlKoa(ctx => {
  return ({
    schema,
    formatError: (err) => ({ message: err.message, status: err.status }),
    context: {
      stationConnector: new StationConnector(),
      passengerTypeConnector: new PassengerTypeConnector(),
      authConnector: new AuthConnector(),
      cookies: ctx.cookies
    }
  })
})

router.post("/graphql", graphqlKoaMiddleware)

As you can see, I have set my formatError to return a message and status but currently only the message is getting returned. The error message comes from the error that I throw in my resolver function.

For example:

const resolvers = {
  Query: {
    me: async (obj, {username, password}, ctx) => {
      try {
        return await ctx.authConnector.getUser(ctx.cookies)  
      }catch(err){
        throw new Error(`Could not get user: ${err}`);
      }
    }
  }
}

My only issue with this method is it is setting the status code in the error message and not actually updating the response object.

Does GraphQL require a 200 response even for failed queries / mutations or can I some how update the response objects status code? If not, How do I set the aforementioned error object status code?

Answer 1

除非 GraphQL 请求本身格式错误，否则 GraphQL 将返回 200 状态代码，即使在其中一个解析器中抛出错误也是如此。这是设计使然，所以没有真正的方法来配置 Apollo 服务器来改变这种行为。

也就是说，您可以轻松连接自己的中间件。您可以导入runHttpQueryApollo 中间件在后台使用的函数。实际上，您几乎可以复制源代码并对其进行修改以满足您的需要：

const graphqlMiddleware = options => {
  return (req, res, next) => {
    runHttpQuery([req, res], {
      method: req.method,
      options: options,
      query: req.method === 'POST' ? req.body : req.query,
    }).then((gqlResponse) => {
      res.setHeader('Content-Type', 'application/json')

      // parse the response for errors and set status code if needed

      res.write(gqlResponse)
      res.end()
      next()
    }, (error) => {
      if ( 'HttpQueryError' !== error.name ) {
        return next(error)
      }

      if ( error.headers ) {
        Object.keys(error.headers).forEach((header) => {
          res.setHeader(header, error.headers[header])
        })
      }

      res.statusCode = error.statusCode
      res.write(error.message)
      res.end()
      next(false)
    })
  }
}