I have productId which is an array of values.
const groupByvalue= [1, 2];
I have products that have multiple product arrays.
const products = [
{
id: 1,
name: 'milk',
qty: 2
},
{
id: 2,
name: 'butter',
qty: 2
},
{
id: 3,
name: 'milk',
qty: 2
},
{
id: 2,
name: 'butter',
qty: 2
},
{
id: 1,
name: 'milk',
qty: 2
},
{
id: 3,
name: 'butter',
qty: 2
},
{
id: 1,
name: 'milk',
qty: 2
},
{
id: 3,
name: 'butter',
qty: 2
}
];
const groupByKey = 'id';
I need to group the products based on the product's id.
conditions
i)groupBy should be based on the groupByvalue with groupBykey array (only groupBy 1 , 2)
ii) after the group it should sum all the qty
expected
[
{
id: 1,
name : "milk",
qty : sum of all qty
},
{
id: 2,
name : "butter",
qty : sum of all qty
}
];
Thanks!!
Using Lodash
var _ = require('lodash');
var groupByValue = [1, 2];
var groupByKey = 'id';
const products = [
{ id: 1, name: 'milk', qty: 2 },
{ id: 2, name: 'butter', qty: 2 },
{ id: 3, name: 'milk', qty: 2 },
{ id: 2, name: 'butter', qty: 2 },
{ id: 1, name: 'milk', qty: 2 },
{ id: 3, name: 'butter', qty: 2 },
{ id: 1, name: 'milk', qty: 2 },
{ id: 3, name: 'butter', qty: 2 }
]
const ans = _(products)
.groupBy(groupByKey)
.map((product) => {
if(groupByValue.includes(product[0].id)){
return {
id: product[0].id,
name: product[0].name,
qty: _.sumBy(product, 'qty')
}
}
})
.value()
console.log(ans.filter(item => item));
Output :-
[ { id: 1, name: 'milk', qty: 6 }, { id: 2, name: 'butter', qty: 4 } ]
No need for lodash whatsoever, this is a native .reduce() task. You may do like;
var groupByValue = [1, 2],
groupByKey = 'id',
products = [ { id : 1
, name: 'milk'
, qty : 2
}
, { id : 2
, name: 'butter'
, qty : 2
}
, { id : 3
, name: 'milk'
, qty: 2
}
, { id : 2
, name: 'butter'
, qty : 2
}
, { id : 1
, name: 'milk'
, qty : 2
}
, { id : 3
, name: 'butter'
, qty : 2
}
, { id : 1
, name: 'milk'
, qty : 2
}
, { id : 3
, name: 'butter'
, qty : 2
}
],
interim = products.reduce( (r,p) => ( groupByValue.includes(p[groupByKey]) && (r[p[groupByKey]] ? r[p[groupByKey]].qty += p.qty
: r[p[groupByKey]] = Object.assign({},p))
, r
)
, {}
),
result = Object.values(interim);
console.log(result);The milk products with id:3 doesn't count.
I would filter the array first, and then make the map,
this can be done in single .reduce(...) function, but its more readable using lodash:
const _ = require('lodash');
const groupByValue = [1, 2];
const groupByKey = 'id';
const products = [
{ id: 1, name: 'milk', qty: 1 },
{ id: 2, name: 'butter', qty: 2 },
{ id: 3, name: 'cheese', qty: 4 },
{ id: 2, name: 'butter', qty: 5 },
{ id: 1, name: 'milk', qty: 3 },
{ id: 3, name: 'cheese', qty: 6 },
{ id: 1, name: 'milk', qty: 1 },
{ id: 3, name: 'cheese', qty: 7 }
];
const result = _(products)
.filter(itm => groupByValue.includes(itm.id))
.groupBy(groupByKey)
.map(arr => {
const { id, name } = arr[0];
return { id, name, qty: _(arr).sumBy('qty') };
})
.value();
console.log(result);
// output: [{ id: 1, name: 'milk', qty: 5},{id: 2, name: 'butter', qty: 7}]