Smooth error handling for Meteor.methods

throwErrorMeteor.js

// in /lib needed on both client and server

var throwError = function(error, reason, details) {
  error = new Meteor.Error(error, reason, details);
  if (Meteor.isClient) {
    return error;
  } else if (Meteor.isServer) {
    throw error;
  }
};

// Some Method

Meteor.methods({
  createPost: function(text) {
    if (!this.userId) {
      return throwError(403, 'Must be logged in');
    }
  }
});