I have a cart with a bunch of products, based on this array:
[
{
product_id: 123,
price: 100,
quantity: 1,
item: { ... some more data }
},
{
product_id: 200,
price: 199,
quantity: 1,
item: { ... some more data }
},
{
product_id: 123,
price: 100,
quantity: 2,
item: { ... some more data }
},
etc...
]
So, when a product has been added multiple times, it should "merge" them into one object and the output to be like:
[
{
product_id: 123,
price: 100,
**quantity: 2,** // THIS IS VERY IMPORTANT
item: { ... some more data }
},
{
product_id: 200,
price: 199,
quantity: 1,
item: { ... some more data }
},
]
So, I’ve tried the following:
const output = Object.values(
items.reduce((accu, { product_id, ...item }) => {
if (!accu[product_id]) accu[product_id] = {}
accu[product_id] = { product_id, ...accu[product_id], ...item }
return accu
}, {}),
)
this actually gives me what I want, EXCEPT that the quantity is summarized.
How can I achieve that?
>Solution :
You have to add the accumulation logic to the quant separately
like the following example
const cart = [
{
product_id: 123,
price: 100,
quantity: 1,
},
{
product_id: 200,
price: 199,
quantity: 1,
},
{
product_id: 123,
price: 100,
quantity: 2,
},
]
const output = Object.values(
cart.reduce((accu, { product_id, ...item }) => {
if (!accu[product_id]) accu[product_id] =
{
quantity:0
}
accu[product_id] = {
product_id,
...accu[product_id],
...item,
quantity: accu[product_id].quantity + item.quantity // custom accu for quant
}
return accu;
}, {}),
)
console.log(output)