Javascript update a array data depending on key

Question

I have a simple array and I want to update this array with the value order:"asc" and want to delete all other order key only if type == "user" and key == "country"

const items = [
 {
 type: "user",
 values: [
 {order:"asc", key:"first_name"},
 {key:"last_name"},
 {key:"address"},
 {key:"country"},
 ]
 },
]

My expected result is

const items = [
 {
 type: "user",
 values: [
 {key:"first_name"},
 {key:"last_name"},
 {key:"address"},
 {order:"asc", key:"country"},
 ]
 },
]

I'm able to do this with map inside map. Is it possible without looping twice?

items.map(
 x => { if (x.type == "user") {
 x.values = x.values.map(y => {
 if (y.key.includes("country")) {
 y.order = "asc"
 } else if (JSON.stringify(x.values).includes("country")) {
 delete y.order
 }
 return y
 })
 }
 return [x]
});

• Andreas: The only actual JSON in your question is the result of JSON.stringify(x.values) - and that call is not necessary and just adds a potential source for unwanted behavior.
• A1exandr Belan: I don't think it's possible to do this without a double loop. Because you have two independent arrays. And each array has to have a loop. Map, filter, foreEach all have a loop under the hood.

Answer 1

I think that you can do that only with double loop. I write this script but it similar to yours.

var newItems = items.map(el => {
 if(el.type === "user"){
 el.values = el.values.map(value => {
 if(value.key === "country"){
 value["order"] = "asc"
 }else if(value["order"] != undefined){
 delete value["order"]
 }
 return value
 })
 return el
 }
})

• kiran: It works if I have {key:"country"},. If I don't have this country key, then it removes the order:asc from the item {order:"asc", key:"first_name"},. I don't want to delete order:"asc", if the values does not contains country.

Answer 2

Logic

• Loop through items array.
• Find nodes with type "type"
• From that nodes loop through values array.
• Clear "order" of nodes where key is not "country"
• Add "order" as "asc" where key is "country"

Working Fiddle

const items = [
 {
 type: "user",
 values: [
 { order: "asc", key: "first_name" },
 { key: "last_name" },
 { key: "address" },
 { key: "country" },
 ]
 },
];
items.filter(item => item.type === "user").forEach(item => {
 item.values.filter(value => value.order === "asc").forEach(value => value.order && value.key !== "country" ? delete value.order : {});
 item.values.filter(value => value.key === "country").forEach(value => value.order = "asc");
});
console.log(items);

Answer 3

items.filter(itm => itm.type == "user")
 .map(u => {u.values.map(v => {
 delete v.order
 if (u.values.key == "country")
 u.values.order = "asc" 
 })
 }
); 

Answer 4

If you don't want to delete order:"asc" if there is no country in the values array then instead of JSON.stringify(x.values).includes("country") upon every object in values you could use .find() and then only loop and delete if there is an object with key:"country":

const items = [ { type: "user", values: [ {order:"asc", key:"first_name"}, {key:"last_name"}, {key:"address"}, {key:"country"}, ] }, ]
const result = items.map(obj => {
 if (obj.type === 'user') {
 const country = obj.values.find(o => o.key === 'country')
 if (country) {
 obj.values.forEach(value => delete value.order)
 country.order = 'asc'
 }
 
 }
 return obj
})
console.log(result)

.as-console-wrapper{min-height:100%}