how to fetch youtube playlist videos using Go on app engine

Using Api key I was able to fetch the videos in a playlist from Api Explorer. Execute without OAuth fetched the results json. Here is the link.<br>
https://developers.google.com/apis-explorer/?hl=en_US#p/youtube/v3/youtube.playlistItems.list?part=snippet&amp;playlistId=PLHyTuYqPkZCzt7mWZ4hmmrRdjLJiw6O2T&amp;_h=2&

Implementing the same call using Go on App engine fails with below error:
<pre>
Get https://www.googleapis.com/youtube/v3/playlistItems?alt=json&amp;part=snippet&amp;playlistId=PLHyTuYqPkZCzt7mWZ4hmmrRdjLJiw6O2T: http.DefaultTransport and http.DefaultClient are not available in App Engine. See https://cloud.google.com/appengine/docs/go/urlfetch/
</pre>

Here is the code I use:
<!-- language : go -->

import (
	"net/http"
	"code.google.com/p/google-api-go-client/googleapi/transport"
	"code.google.com/p/google-api-go-client/youtube/v3"
	"log"
)

    var service *youtube.Service
    func init() {
    	var err error
    	log.Println("Apikey = ", apiKey)
    	client := &http.Client{Transport: &transport.APIKey{Key: apiKey}}
    	service, err = youtube.New(client)
    	if err != nil {
    		log.Println("ERROR in creating youtube New client ", err)
    	}
    	var items *youtube.PlaylistItemListResponse
    	if items, err = service.PlaylistItems.List("snippet").PlaylistId("PLHyTuYqPkZCzt7mWZ4hmmrRdjLJiw6O2T").Do(); err != nil {
    		log.Println("Error in fetching playlist items ", err) //this line shows the error
    	}
    	log.Println(Jsonify(items))
    }

As of now, I run my code on local dev server i.e goapp serve

What is missing? How do I fetch youtube playlist videos using v3 api and ApiKey?

Unfortunately, the linked doc doesn't quite explain why your code isn't working. On App Engine, you need to use a special http.Transport provided by the urlfetch package; see https://cloud.google.com/appengine/docs/go/urlfetch/

Found the solution. Below code did the task for me.

<!-- language: go -->

func FetchVideos(w http.ResponseWriter, r *http.Request) {
    var service *youtube.Service
    ctx := appengine.NewContext(r)
    
    transport := &transport.APIKey{
    	Key:       apiKey,
    	Transport: &urlfetch.Transport{Context: ctx}}
    client := &http.Client{Transport: transport}
    
    var err error
    service, err = youtube.New(client)
    if err != nil {
    	log.Println("ERROR in creating youtube New client ", err)
    }
    var items *youtube.PlaylistItemListResponse
    if items, err = service.PlaylistItems.List("snippet").PlaylistId("PLHyTuYqPkZCzt7mWZ4hmmrRdjLJiw6O2T").Do(); err != nil {
    	log.Println("Error in fetching playlist items ", err)
    }
    log.Println(Jsonify(items))