(Quick Reference)
chain
Purpose
Uses
flash storage to implicitly retain the model following an HTTP redirect from one action to another.
Examples
def shawshankRedemption = new Book(title: 'The Shawshank Redemption')
chain(action: "details", model: [book: shawshankRedemption])
Description
Usage:
chain(controller*, action, id*, model, params*)
Arguments:
uri
- The full uri to redirect to (example /book/list, book/show/2)
controller
(optional) - The controller to redirect to; defaults to the current controller if not specified
action
- The action to redirect to, either a string name or a reference to an action within the current controller
id
(optional) - The id to use in redirection
model
- The model to chain to the next action
params
(optional) - Parameters to pass to the action chained to.
The chain method stores the passed model in flash scope and then performs an HTTP redirect. The model is then restored for the next request. The model that will eventually be passed to the view will be created by starting with the model that was passed to the chain method and then adding to that all of the data that is in the model returned by the next action, which may replace some of the data that was in the model originally passed to the chain method. For example:
def one() {
chain action: 'two', model: [name: 'Tony', town: 'Birmingham']
}def two() {
[name: 'Anthony', country: 'England']
}
If a request is sent to the
one
action, that action chains to the
two
action which returns a model. The model that is passed to the view would contain
[name: 'Anthony', town: 'Birmingham', country: 'England']
The chain method requires either a URI to redirect to
or a controller/action/id name combination