javascript - React: Uncaught (in promise) SyntaxError: Unexpected token < in JSON at position 0

Question

我正在学习教程，但我被困在这部分。多次根据源代码检查我的代码，并用谷歌搜索了这个错误。有很多结果，但我似乎无法将解决方案应用到我的项目中。

我正在使用反应、表达、redis。这是负责 json 数据的文件

根目录 > 反应目录 > src > App.js

import React from 'react'
import './App.css'

import Jobs from './Jobs'

const JOB_API_URL = 'http://localhost:3000/'

async function fetchJobs(updateCb) {
    const res = await fetch(JOB_API_URL)
    const json = await res.json()
    
    updateCb(json)
}


function App() {

    const [ jobList, updateJobs ] = React.useState([])
  
    React.useEffect(() => {
        fetchJobs(updateJobs)
    }, [])
    
    return (
      <div className="App">
        <Jobs jobs={ jobList } />
      </div>
    );
}

export default App  

根目录 > 工作目录 > 任务目录 > fetch-github.js

const fetch         = require('node-fetch')

const redis         = require('redis')
const client        = redis.createClient()

const { promisify } = require("util");
const setAsync      = promisify(client.set).bind(client);

const baseURL = 'https://jobs.github.com/positions.json'

async function fetchGithub() {
    
    let resultCount = 1 
    let onPage      = 0
    let allJobs     = []
    
    // fetch all pages
    while( resultCount > 0 ) {
      
      const res  = await fetch(`${baseURL}?page=${onPage}`)
      const jobs = await res.json()
      
      allJobs.push(...jobs)
      resultCount = jobs.length
      console.log('got', jobs.length, 'jobs')
      onPage++
      
    }
    
    console.log('got ' + allJobs.length + ' jobs total' )
    
    // filter algorithm
    const jrJobs = allJobs.filter(job => {
      
        const jobTitle = job.title.toLowerCase()
        let isJunior = true
        
        // logic
        if (jobTitle.includes('senior') || jobTitle.includes('manager') ||
            jobTitle.includes('sr.') || jobTitle.includes('architect')) {
            
            return false
        }   
        return true
    })
    
    console.log('filtered down to ' + jrJobs.length)
    
    // set in redis
    const success = await setAsync('github', JSON.stringify(jrJobs))
    
    console.log({success})
}

module.exports = fetchGithub

根目录 > api 目录 > index.js

const express       = require('express')
const app           = express()
const port          = 3001

const redis         = require('redis')
const client        = redis.createClient()

const { promisify } = require("util");
const getAsync      = promisify(client.get).bind(client);

app.get('/jobs', async (req, res) => {
    const jobs = await getAsync('github')
    res.header('Access-Control-Allow-Origin', 'http://localhost:3000')
    
    return res.send(jobs) 
})

app.listen(port, () => {
    console.log(`Example app listening at http://localhost:${port}`)
})

标签： javascriptreactjsredis