Grails forms & URL mapping - forms

Question

I am writing a Grails app where I would like to setup a form that allows a user to type in an image ID number and this value will be passed to a controller / action that retrieves the image from S3 for the given image ID.
The desired url would be of the format example.com/results/1234. I have setup the following URL mappings:
class UrlMappings {
static mappings = {
"/$controller/$action?/$id?"{
constraints {
// apply constraints here
}
}
"/results/$id?" {
controller = "s3Image"
action = "getS3Image"
}
"/"(view:"/index")
"500"(view:'/error')
}
}
The following is how I have setup a form:
<g:form controller="results" method="get">
<input type="text" name="id" class="input-xxlarge" placeholder="http://www.example.com">
<button class="btn btn-inverse">Submit</button>
</g:form>
However this seems to submit the form to example.com/results?id=12345.
How would I alter my form or mappings such that I can produce the desired url after form submission?
Thanks!

Answer 1

<g:form controller="results" method="get">
will generate an HTML form whose action URL is /results (the reverse URL mapping for a controller named "results" with no action or id). When this form is submitted, the browser will add ?id=1234 to the end of this URL because the form method is GET. This is not something you can influence in your URL mappings on the server side.
Instead, you should have your form POST to a different controller action that redirects to the getS3Image action. The redirect will have access to the ID on the server side, so can generate the friendly-looking URL for the redirect.
UrlMappings:
"/results/$id?" {
controller = "s3Image"
action = "getS3Image"
}
"/findImage" {
controller = "s3Image"
action = "find"
}
S3ImageController:
def find() {
redirect(action:"getS3Image", id:params.id)
}
def getS3Image() {
// as before
}
GSP:
<g:form controller="s3Image" action="find" method="post">
<input type="text" name="id" class="input-xxlarge" placeholder="http://www.example.com">
<button class="btn btn-inverse">Submit</button>
</g:form>

Answer 2

Derek,
what you are seeing is correct behaviour. For the GET request you have two things
URL of request
Parameters
Parameters are appended after urls using urlencode and separated by &, so, when you have form with URL http://mydomain.com/controller/action/, and in this form you have two fields: id, name, then, upon submission, they will be passed like this: http://mydomain.com/controller/action/?id=3&name=someName
URLMappings are mapping only URL part of it. So, in your example UrlMapping are matched only to /results/ and id is not passed.
But that is ok, since you can still access the id parameter in your controller, just do it like this (inside s3Image controller):
def getS3Image() {
def id = params.id
}

Answer 3

Try very simple change in UrlMapping:
"/results/$id?" {
controller = "s3Image"
action = "getS3Image"
id = $id
}
and then for sure you have the id accessible in the s3Image controller via:
def id = params.id

Answer 4

I think you have two problems here. First, UrlMappings rules are matched in order of appearance, from top to bottom. First rule that grails matches is "/$controller/$action?/$id?". Move your rule "/results/$id?" above and it should take precedence. - check comment below post.
Your second mistake is declaration of form. I think you've meant:
<g:form controller="s3Image" method="getS3Image">