Jammming: Unhandled Rejection (TypeError): Cannot read property '0' of undefined

Finishing up the Jammming project and typed in a search and the following showed up:

{{ Unhandled Rejection (TypeError): Cannot read property ‘0’ of undefined

(anonymous function)


  41 | return jsonResponse.tracks.items.map(track => ({  42 |   id: track.id,  43 |   name: track.name,> 44 |   artist: track.artist[0].name,     | ^  45 |   album: track.album.name,  46 |   uri: track.uri  47 | }));

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(anonymous function)


  38 | if (!jsonResponse.tracks) {  39 |   return [];  40 | }> 41 | return jsonResponse.tracks.items.map(track => ({     | ^  42 |   id: track.id,  43 |   name: track.name,  44 |   artist: track.artist[0].name,

View compiled

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Hey @charleskallick4619, The error message is basically saying that track.artist is undefined. You are using track.**artist** instead of track.artist**s**. Also, the instructions say "Artist - returned as track.artist**s**[0].name.

I hope this will help you!


Should be using console.log() to debug/check your code if you get stuck and compare with what you are expecting to see.


1 Like

got it taken care of. thank you!

TypeError: Cannot read property ‘0’ of undefined
at IncomingMessage , im having similar problem can someone help please.

Weather App
    <form action="/" method="POST">
    <label for="cityInput">cityName: </label>
    <input id="cityInput" type="text" name="cityName">
    <button type="submit">GO</button>

    <script src="" async defer></script>

//here is my app.js code//

const express=require(“express”);

const https=require(“https”);

const bodyParser=require(“body-parser”);

const {response}=require(“express”);

const app=express();



res.sendFile(__dirname +"/index.html");


app.post("/",function(req, res){

const query=req.body.cityName;

const appId=“cbb82ce079c621c839ff84be7f96ca23”;

const units=“metric”;

const url=“https://api.openweathermap.org/data/2.5/weather?q=”+ query +"&appid “+ appId +”=&units=" + units;



const weatherData  =JSON.parse(data);

const icon=weatherData.weather[0].icon;

const weatherDiscription=weatherData.weather[0].description

const imageURL="http://openweathermap.org/img/wn/"+ icon+"@2x.png";

 const temp=weatherData.main.temp;

 res.write("<h1>the temperature in "+ query +" is " + temp + "degrees Celcius</h1>");

 res.write("<p>The current weather is " +  weatherDiscription + "</p>");

 res.write("<img src=" + imageURL +">");




app. listen(3000,function(req, res){

 console.log("the sever is running at port 3000");

}) ;