Not returning value in vue function - vue.js

Question

I'm using vue and I'm trying to return a user's email. I have 2 separate functions and one gets all the products while the other one
is supposed to get the user emails that is attached to that product.
The issue I'm having is that the emails isn't showing up and I'm getting an undefined as well.
Here is my code
<template>
<div class="card" style="width: 100%;">
<div class="card-body">
<table class="table">
<thead>
<tr>
<th scope="col">Email</th>
<th scope="col">Product</th>
</tr>
</thead>
<tbody>
<tr v-for="product in products">
<td>
{{ getProductUser(product.user_id) }}
</td>
<td>
{{ product.action }}
</td>
<td>
{{ product.options }}
</td>
<td>
{{ product.created_at }}
</td>
</tr>
</tbody>
</table>
</div>
</div>
</template>
<script>
export default {
props:['id', 'user', 'product'],
data(){
return {
products: [],
}
},
methods: {
getProducts(){
axios.get('/api/products/'+this.id+'/product').then(response => {
this.products = response.data.products;
});
},
getProductUser(user){
axios.get('/api/product/'+user).then(response => {
return response.data.email;
});
}
},
mounted() {
this.getProducts();
}
}
</script>

Answer 1

Apart from the fact that product.user_id is undefined as stated in the comment, you have another issue.
getProductUser doesn't return an email. It returns a promise that will provide an email.
Simplest solution would be
<td>
{{ product.userEmail }}
</td>
(which is by the way an equivalent to <td v-text="product.userEmail"/>, vue templates can be much cleaner than standard HTML).
getProducts(){
axios.get('/api/products/'+this.id+'/product').then(response => {
this.products = response.data.products;
this.products.forEach(product => {
axios.get('/api/product/'+user).then(response => {
product.userEmail = response.data.email;
});
})
});
This should work, but keep in mind that executing additional request per product is generally a bad idea, the performance would be much better if /api/products/{id}/product would have userEmail property already initialized.