Store Facebook graph profile picture URL in User Metadata

gistfile1.txt

function (user, context, callback) {
  
  if(context.connection !== 'facebook'){
    callback(null, user, context);
  }
  
  if(!user.user_metadata.fb_profile_pic){
    
    user.user_metadata = user.user_metadata || {};
    var fb_identity = _.where(user.identities,{provider: "facebook"}); 
    user.user_metadata.fb_profile_pic = 'http://graph.facebook.com/' + fb_identity[0].user_id + '/picture';

    auth0.users.updateUserMetadata(user.user_id, user.user_metadata)
     .then(function(){
      callback(null, user, context);
    })
    .catch(function(err){
        callback(err);
    });
  }
    
}