Sails.js : Youtube API V3 with Node.js

I try to connect Youtube Data API with Node.js in Sails.js, but I've a problem with "fs.readFile" function.

When I launch service it returns "undefined".

Here is my code for YoutubeService :

module.exports = {

callYoutubeApi: function (req, res) {
    // Load client secrets from a local file.
    fs.readFile('api/services/client_secret.json', function processClientSecrets(err, content) {
        if (err) {
            sails.log('Error loading client secret file: ' + err);
            return "error";
        }
        // Authorize a client with the loaded credentials, then call the YouTube API.
        sails.log('123');
        return YoutubeService.authorize(JSON.parse(content), YoutubeService.getChannel);
    });
},

The call in my controller :

channelData = YoutubeService.callYoutubeApi();
sails.log(channelData);

The error :

debug: undefined
debug: 123

I think the call is not working and it can't read the "processClientSecrets" function.

If someone have an idea to help me thanks !

via Benjamin Arthuys