Making API request using Request module in node.js app

Question

I have the following request call in my node.js app

   request({ url:chanURL, qs:chanProperties}, function(err, response, body) {
      if(err) { console.log(err); return; }
      body = JSON.parse(body);

      (function (body) {
        Object.keys(body.items).forEach(function(item) {
            pid = item.contentDetails.relatedPlaylists.uploads;
            console.log(pid);
        })
      })();
    })

And, I'm getting TypeError: Cannot read property 'items' of undefined while processing the response.

The JSON object that I'm trying to work with is

{ kind: 'youtube#channelListResponse',
  etag: '"0KG1mRN7bm3nResDPKHQZpg5-do/B7stMlWJTBpmW2q34yWKIzz8fF8"',
  pageInfo: { totalResults: 1, resultsPerPage: 1 },
  items: 
   [ { kind: 'youtube#channel',
       etag: '"0KG1mRN7bm3nResDPKHQZpg5-do/vV2FFZUI5inz53NuQDJMTs3tdQk"',
       id: 'UCwy6X3JB24VTsDFqMwdO5Jg',
       contentDetails: [Object] } ] }

Why does it say items is undefined?

And I also would like to know if I want to execute the function within this request wrapper, I need to wrap it inside the parenthesis like I did? I did get syntax error without the parenthesis.

joews · Accepted Answer · 2015-10-25 22:01:32Z

3

There are a few problems with your code:

(function (body) { /* ... */ })()

You're calling the anonymous function without an argument. body is therefore undefined inside the function. You should omit the IIFE - it doesn't help you here.

Object.keys(body.items)

Object.keys returns an array of the property names for an Object. body.items is an Array, so you don't need to use it - you should iterate over the object directly.

pid = item.contentDetails.relatedPlaylists.uploads

contentDetails is an Array. If you mean to use the first element, your code should read: item.contentDetails[0].relatedPlaylists.uploads

Making those changes leaves you with:

request({ url:chanURL, qs:chanProperties}, function(err, response, body) {
  if(err) { console.log(err); return; }
  body = JSON.parse(body);

  body.items.forEach(function(item) {
      pid = item.contentDetails[0].relatedPlaylists.uploads;
      console.log(pid);
  })
})

edited Oct 25, 2015 at 22:01

answered Oct 25, 2015 at 21:55

joews

30.4k11 gold badges82 silver badges91 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Seong Lee Over a year ago

Thank you for your insightful answer, this is really helpful. Would you mind adding how I can structure so I can call another another request call in a chain or using callback? Now I got the playlist ID of my Youtube, I need to make another similar request to get the list of videos using this playlist ID. I know how to get the videos but I'm not sure how to put these two requests together to ultimately get the video data.

Collectives™ on Stack Overflow

Making API request using Request module in node.js app

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related