Grails GSP-model injection bug

I have the following Grails 2.3.6 controller:

@Slf4j
class FizzController {
    def index() {
        List<Widget> widgets = getSomehow()

        log.info("About to render foo.gsp with ${widgets.size()} widgets.")

        render (
            view: "foo",
            model: widgets
        )
    }
}

Where foo.gsp is:

<!DOCTYPE html>
<html>
<head>
    <omitting a bunch of stuff for brevity>
</head>
<body>
    <h3>Widget List:</h3>
<g:each in="${widgets}" var="widget" >
    <h2>Name: ${widget.name}, Type: ${widget.type}</h3>
</g:each>
</body>
</html>

When I do a Grails run-app and navigate my browser to:

http://localhost:8080/myapp/fizz

I see my foo GSP view/page (with the <h3> header tag), however it doesn't display anything else. When I view the page source code, I see:

<div id="page-body">
    <h3>Widget List:</h3>
</div>

This indicates that I am injecting an empty List<Widget>, right?

However in my log output, I see:

About to render foo.gsp with 1 widgets.

So it actually seems like I do have a non-empty List<Widget>, but apparently I'm not properly injecting it into my GSP. So what's going on here?

Solution

you are passing the wrong model, it should be a map:

    List<Widget> widgets = getSomehow()

    render (
        view: "foo",
        model:[ widgets:widgets ]
    )

then you can access it in your gsp:

<g:each in="${widgets}" var="widget" >
  <h2>Name: ${widget.name}, Type: ${widget.type}</h3>
</g:each>