Getting JSON back from rails with respond_with

Question

I have a jquery ajax call that goes to the create action, and I need to get the response back as JSON to then do something with it on the page in the success ajax function, but for some reason with rails it keeps throwing a missing template error:

class MembersController < ApplicationController
  respond_to :json

  def create
    @member = @group.members.build
    @member.user_id = params[:user_id]
    respond_with(@member) if @member.save
  end
end

Should I be rendering nothing at all?

Answer 1

If @member.save fails, then the default rendering will take place, which means that rails will try to render create.*.erb, or create.rjs, etc. You probably want to do

def create
  @member = @group.members.build
  @member.user_id = params[:user_id]
  if @member.save
    respond_with(@member)
  else
    render :nothing => true
  end 
end