CASL - Vue 3 - Element not showing for role - vue.js

Question

I am having a bit of a challenge implementing CASL in my app.
I have created the following composable useAppAbility ("hook") that defines all the rules:
import { AbilityBuilder, createMongoAbility, subject } from "#casl/ability";
import { useAbility } from "#casl/vue";
const service = {};
const user = {};
const subscription = {};
const invoice = {};
const account = {};
const ability = createMongoAbility();
const ROLES = ["admin", "account_owner", "beneficiary", "super_admin"];
const defineAbilityFor = (role: Object) => {
const { can, rules } = new AbilityBuilder(createMongoAbility);
const is = (r: string) => {
return ROLES.indexOf(r) >= ROLES.indexOf(role);
};
if (is("admin")) {
can("add", subject("User", user));
can("remove", subject("User", user));
}
return ability.update(rules);
};
export { defineAbilityFor, ability, subject };
export const useAppAbility = () => useAbility();
Added the plugin to the main.ts:
import { ability } from "#/composables/useAppAbility";
import { abilitiesPlugin } from "#casl/vue";
createApp(App)
.use(abilitiesPlugin, ability, {
useGlobalProperties: true,
})
//stuff
.mount("#app");
And then, I found that using the beforeEach hook in the router and passing in the user before each route was the simplest way to deal with page load and SPA routing.
I have therefore added the following to my router/index.ts:
import { ability, defineAbilityFor } from "#/composables/useAppAbility";
import useAuth from "#/composables/useAuth";
const {
getUserByClaims,
} = useAuth();
// routes
router.beforeEach(async (to, _from, next) => {
defineAbilityFor(getUserByClaims.value.roles)
})
At this stage I can verify that the user is being passed properly to the defineAbilityFor function and when using the ability.on("update") hook to log the rules object, I have the following output:
Which seems to confirm that the rules for this user are built and updated correctly?
However, when trying to display a button for the said admin in a component, the button does not show.
MyComponent.vue:
<script setup lang="ts">
import { useAppAbility, subject } from "#/composables/useAppAbility";
const { can } = useAppAbility();
</script>
<template>
<div v-if="can('add', subject('User', {}))">TEST FOR CASL</div> <!-- DOES NOT SHOW-->
</template>
Not sure where to go from there, any help would be appreciated.
Thanks