How to use the lodash _groupBy

Question

This is how my json looks like:

 invoices = { "count": 1 "data": Array(0)[{ "company": "ABC PLC", "customer": { "name": "XYZ" }, "invoiceFees": Array(2)[ 0: { "quarter": { "q_name": "A", "description": "payments for quarter A" } }, 1: { "quarter": { "q_name": "B", "description": "payments for quarter B" } } ] }] }

I am trying to group invoice results by Quarter. This is how I am doing it:

console.log(_.groupBy(invoices.data.invoiceFees, 'quarter.q_name'));

This slices everything down to an empty result like this:

invoices = {}

What am I doing wrong here?

My desired output sould be something of this sort:

 invoices = { "data": [{ "company": "ABC PLC", "customer": { "name": "XYZ" }, "invoiceFees": [{ "quarter A: { "description": "payments for quarter A" }, "quarter B: { "description": "payments for quarter B" } }] }] }

Answer 1

Ok, for your specific example, the following produces the result you're after:

invoices = {
    data: _.map(invoices.data, d => _.assign(
        _.omit(d, 'invoiceFees'),
        _.fromPairs(
            _.map(d.invoiceFees, f => [
                'quarter ' + f.quarter.q_name,
                _.omit(f.quarter, 'q_name')
            ])
        )
    ))
}

if you need invoiceFees as a separate object, then

invoices = {
    data: _.map(invoices.data, d => _.assign(
        d,
        {invoiceFees: _.fromPairs(
            _.map(d.invoiceFees, f => [
                'quarter ' + f.quarter.q_name,
                _.omit(f.quarter, 'q_name')
            ])
        )}
    ))
}