grails render collection as single json object

Question

For example I have next Domain class

User{
   String name
}

Also I have 2 objects of this class

new User(name: "John").save()
new User(name: "Alex").save()

How should look "list" action in UserController to represent User.list() in JSON format like this

{1: "John", 2: "Alex"}

Let me be more precise. I want something like this:

UserController{
   def list = {
    render(contentType: "text/json") {
        User.list().each {user->
            user.id = user.name
        }
    }
}

But sadly this isn't working.

Answer 1

I couldn't find solution with JSONBuilder API. Because of that I made my solution with help of org.codehaus.jackson.

response.setContentType("text/json")
JsonGenerator g = jsonFactory.createJsonGenerator(response.getOutputStream())
g.writeStartObject()
for (user in users) {
    g.writeStringField(user.id.toString(), user.name)
}
g.writeEndObject()
g.close()