Ramda - how to merge 2 or more arrays of objects - ramda.js

Question

I am trying to merge arrays of objects into one clean array using Ramda but I need some help. I have sample JSON which is below. In this example, I have 2 groups but the number of groups can be 3, 4, 10. I am interested in tableItems array from each group.
const groups = [
{
id: '',
name: '',
tableItems: [
{
id: 1,
name: 'John'
},
{
id: 2,
name: 'Paul'
},
{
id: 3,
name: 'Mary'
}
]
},
{
id: '',
name: '',
tableItems: [
{
id: 10,
name: 'Brian'
},
{
id: 20,
name: 'Joseph'
},
{
id: 30,
name: 'Luke'
}
]
}
];
I tried something like this:
let mapValues = x => x.tableItems;
const testItems = R.pipe(
R.map(mapValues)
)
And then I got arrays of my tableItems and now I would like to merge them into one array.
[
[
{
"id": 1,
"name": "John"
},
{
"id": 2,
"name": "Paul"
},
{
"id": 3,
"name": "Mary"
}
],
[
{
"id": 10,
"name": "Brian"
},
{
"id": 20,
"name": "Joseph"
},
{
"id": 30,
"name": "Luke"
}
]
]
Any help would be appreciated.

Answer 1

Use R.chain to map and flatten, and get the tableItems using R.prop:
const fn = R.chain(R.prop('tableItems'));
const groups = [{"id":"","name":"","tableItems":[{"id":1,"name":"John"},{"id":2,"name":"Paul"},{"id":3,"name":"Mary"}]},{"id":"","name":"","tableItems":[{"id":10,"name":"Brian"},{"id":20,"name":"Joseph"},{"id":30,"name":"Luke"}]}];
const result = fn(groups);
console.log(result);
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