Grails has built in support for handling duplicate form submissions using the "Synchronizer Token Pattern". To get started you need to define a token on the form tag:<g:form useToken="true" ...>
Then in your controller code you can use the withForm method to handle valid and invalid requests:withForm {
// good request
}.invalidToken {
// bad request
}
If you only provide the withForm method and not the chained invalidToken
method then by default Grails will store the invalid token in a flash.invalidToken
variable and redirect the request back to the original page. This can then be checked in the view:<g:if test="${flash.invalidToken}">
Don't click the button twice!
</g:if>
The withForm tag makes use of the session and hence requires session affinity if used in a cluster.