请求在 Graphql 解析器中未定义，但在中间件中包含一些值。 （节点，快递）

Posted 2023-03-08

【中文标题】请求在 Graphql 解析器中未定义，但在中间件中包含一些值。 （节点，快递）

【英文标题】：Request is undefined in Graphql Resolver but contains some value in Middleware. (Node, Express)

【发布时间】：2020-04-26 22:31:27

【问题描述】：

我正在尝试使用 jwt 令牌对 User 进行身份验证，并将 userId 和身份验证检查添加到请求（req）中，如中间件文件所示，这里是 req.isAuth 返回 true。

问题是相同的req 在 Graphql 的 Resolver 中是 undefined 的，因此不再授予 api 使用权限。

任何帮助将不胜感激。 谢谢

app.js

const express = require('express');
const bodyParser = require('body-parser');
const graphqlHttp = require('express-graphql');
const mongoose = require('mongoose');

const isAuth = require('./middleware/is-auth');

const graphQlSchema = require('./graphql/schema/index');
const graphQlResolvers = require('./graphql/resolvers/index');

const app = express();

app.use(bodyParser.json());
app.use(isAuth);

app.use((req, res, next)=>
    console.log(req);
    res.setHeader('Access-Control-Allow-Origin','*');
    res.setHeader('Access-Control-Allow-Methods', 'POST,GET,OPTIONS');
    res.setHeader('Access-Control-Allow-Headers', 'Content-Type,Authorization');
    if (req.method === 'OPTIONS')
        return res.sendStatus(200);
    
    next();

);

app.use('/graphql', graphqlHttp(
    schema: graphQlSchema,
    rootValue: graphQlResolvers,
    graphiql: true
));

mongoose.set('useCreateIndex', true);

mongoose.connect(`mongodb+srv://user:[e-mail]/project-name?retryWrites=true&w=majority`,  useNewUrlParser: true, useUnifiedTopology: true ).then(() =>
    app.listen(process.env.PORT || 3002);
).catch(err => 
    console.log(err);
);

中间件 is-auth.js

const jwt = require('jsonwebtoken');

module.exports = (req, res, next) => 
    const authHeader = req.get('Authorization');
    if(!authHeader)
        req.isAuth = false;
        return next();
    
    const token = authHeader.split(' ')[1];

    if(!token || token === '')
        req.isAuth = false;
        return next();
    
    let decodedToken;
    try 

        decodedToken = jwt.verify(token, 'supersecret');
    catch(err)
        req.isAuth = false;
        return next();
    

    if(!decodedToken)
        req.isAuth = false;
        return next();
    
    req.isAuth = true;
    req.userId = decodedToken.userId;
    console.log(req.isAuth); // returns TRUE
    next();

GraphQl-Resolver

const User = require('../../models/user');
const Post = require('../../models/post');
const Comment = require('../../models/comment');

const jwt = require('jsonwebtoken');

module.exports = 
    fetchPosts: async (req) => 
        console.log(req.isAuth); // This returns Undefined
        if(!req.isAuth)
            throw new Error("Not Authorised to access this feature");
        
        try
            const userId = req.userId; //"5e0edd18845b912b244a1990";

            const following = await User.findOne(_id: userId);

            const postList =  new Array;

            await Promise.all(following.map( async eachUser => 
                const createdPosts = await User.findOne(_id: eachUser);
                await Promise.all(createdPosts.map(async eachPost => 
                    const postDetail = await Post.findOne(_id: eachPost);

                    await postList.push(postDetail);
                ));
            ));

            return postList;
        catch(err)
            throw(err);
        

    ,

【参考方案1】：

我自己解决了。

问题发生在仅传递 req 作为参数时。

解决方案： 同时传递 args 和 req 解决了这个问题。