Override/enhance controller/view functions

[mikegrogan]

Since plugins are going away eventually I'm trying to replace jsconfirm (https://forgebox.io/view/cfwheels-js-confirm) with something directly in my app code. Doesn't seem like it needs to be a package.

I'm trying to figure out the best approach to overriding the linkto() function.

I see this https://guides.wheels.dev/v3-0-0/working-with-wheels/overriding-core-methods/ talking about using something like superlinkto(). In reviewing some of the vendor code it doesn't seem like that only applies to models. Either way, I'm having trouble getting anything to work. Even tried some Google Gemini help.

To enhance the linkto() and buttonto() built in functions with a js confirmation:

• Should I be user superlinkto()? I can dump out core and see the linkto() function but in trying to override it I get http 500 errors, among other things
• Where should I be making this tweak? app/controllers/controller.cfc? app/global/functions.cfm? app/views/helpers.cfm?

I know this is probably an easier question. Thanks for any help if someone has done something similar.

[bpamiri]

Good question — and you've hit a real rough edge, so let me untangle it. Everything below is copy-paste-tested against 4.0.x (develop).

Why superlinkto() gave you 500s

The super-prefixed convention from that guide is currently implemented for models only. When you override a core method on a model, the framework registers the original as super<name>() — but controllers and view helpers never get that branch, so superLinkTo() is simply undefined there, and calling it errors. The guide over-promises; I've filed #3325 to bring controllers/views to parity and to fix the docs.

The good news: you don't need to override anything

linkTo() and buttonTo() pass any extra named argument straight through as an HTML attribute, and camelCased data* argument names are automatically hyphenized (a hyphen isn't legal in a CFML argument name):

#linkTo(text="Delete", route="post", key=post.id, method="delete", dataConfirm="Are you sure?")#
<!--- renders: <a data-confirm="Are you sure?" href="..."> --->

#buttonTo(text="Delete", route="post", key=post.id, method="delete", dataConfirm="Are you sure?")#
<!--- renders: <form data-confirm="Are you sure?" ...> --->

Then one small delegated listener in your layout replaces the whole jsconfirm plugin:

<script>
document.addEventListener("click", function (e) {
	var el = e.target.closest("a[data-confirm]");
	if (el && !confirm(el.getAttribute("data-confirm"))) {
		e.preventDefault();
		e.stopImmediatePropagation();
	}
}, true);
document.addEventListener("submit", function (e) {
	var f = e.target;
	if (f.matches("form[data-confirm]") && !confirm(f.getAttribute("data-confirm"))) {
		e.preventDefault();
	}
}, true);
</script>

If you want the old confirm= argument back

The right home is app/views/helpers.cfm (your third guess). That file is included into every controller before the framework mixes in its own helpers, and the mixin step skips any function name that already exists — so your version wins in both controllers and views. To call the original, capture a reference to it yourself:

<cfscript>
// app/views/helpers.cfm
variables.coreLinkTo = CreateObject("component", "wheels.view.links").linkTo;

public string function linkTo() {
	if (StructKeyExists(arguments, "confirm")) {
		// Bracket syntax preserves the key's case so it renders as data-confirm.
		// (A dot-set like arguments.dataConfirm = ... loses the casing and you'd
		// get a "dataconfirm" attribute instead.)
		arguments["dataConfirm"] = arguments.confirm;
		StructDelete(arguments, "confirm");
	}
	return coreLinkTo(argumentCollection = arguments);
}
</cfscript>

Why this works: CFML function references late-bind to whatever object they're invoked on, so coreLinkTo runs in your controller's context with urlFor() etc. available — it's the exact same trick the framework uses internally to wire helpers in. buttonTo can be wrapped the same way (same wheels.view.links component); note its plain extra args land on the <form> tag, while input-prefixed ones land on the button.

As for the other two locations you tried: app/global/functions.cfm is the wrong layer for a view helper, and a public method on app/controllers/Controller.cfc technically works but mixes helper code into your controller surface — helpers.cfm is the intended home.

Once #3325 lands you'll be able to just call superLinkTo(argumentCollection = arguments) without the CreateObject line.

[mikegrogan]

Great stuff. Thanks @bpamiri !