Enable nested id and parentId properties

[gregoryforel]

Here's my data structure:

    const array = [
        {  data: { id: 'id1', parent: 'idparent' , otherdata...} },
        {  data: { id: 'id2', parent: 'id1' , otherdata...} },
        {  data: { id: 'id3', parent: 'id1' , otherdata...} }
    ]

id and parentId are nested inside data in my case, and I'd bet it is not uncommon.

Would you amend your code this way to make this scenario work?

Add this:

    const getItemNestedProperty = (item: Item, nestedProperty: string): string => {
	return nestedProperty.split('.').reduce((o, i) => o[i], item)
    }

Replace

    const itemId = item[conf.id]
    const parentId = item[conf.parentId]

with:

    const itemId = getItemNestedProperty(item, conf.id)
    const parentId = getItemNestedProperty(item, conf.parentId)

Thanks!

[philipstanislaus]

@gregoryforel that's a valuable addition, happy to add it. Would you submit a PR for that change? Many thanks!

[gregoryforel]

@philipstanislaus sure, done

[philipstanislaus]

Landed in #21. Thanks again for your contribution 💪