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There are a few useful conventions you can follow when creating JSON views. For example if you have a domain class called `Book`, then creating a template located at `grails-app/views/book/_book.gson` and using the link:../ref/Controllers/respond.html[respond] method will result in rendering the template:

[source,groovy]
----
def show(Long id) {
    respond Book.get(id)
}
----

In addition if an error occurs during validation by default Grails will try to render a template called `grails-app/views/book/_errors.gson`, otherwise it will try to render `grails-app/views/errors/_errors.gson` if the former doesn't exist.

This is useful because when persisting objects you can `respond` with validation errors to render these aforementioned templates:

[source,groovy]
----
@Transactional
def save(Book book) {
    if (book.hasErrors()) {
        transactionStatus.setRollbackOnly()
        respond book.errors
    }
    else {
        // valid object
    }
}
----

If a validation error occurs in the above example the `grails-app/views/book/_errors.gson` template will be rendered.

For more information on JSON views (and Markup views), see the http://views.grails.org/latest/[JSON Views user guide].
