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A better way to deal with objects using many nested forEach?

I would like to know if there is a better way to deal with nested forEach when it comes to dealing with objects with properties that are nested arrays themselves.
My object (summarized):
{
...,
"tx_responses": [
{
...
"logs" : [
{
...,
"events": [
{
"type": "coin_received",
"attributes": [
{
"key": "receiver",
"value": "somesome"
},
{
"key": "amount",
"value": "somesome"
}
]
},
...
{
"type": "transfer",
"attributes": [
{
"key": "recipient",
"value": "somesome"
},
{
"key": "sender",
"value": "somesome"
},
{
"key": "amount",
"value": "somesome"
}
]
},
{
"type": "withdraw_rewards",
"attributes": [
{
"key": "amount",
"value": "somesomesomehere"
},
{
"key": "validator",
"value": "somesome"
}
]
},
...
]
}
],
...
I am essentially trying to extract all { key: 'amount', value: 'somesomesomehere' } objects in the "attributes" array of the "type" : "withdraw_rewards" object in the "events" array.
Currently this is the code I wrote to carry out my task:
getWithdrawnAmounts: async(del_addr_) => {
let withdrawnAmounts = [];
const res = await axios.get("some_url_that_uses_del_addr_");
res.data.tx_responses.forEach(txr => {
txr.logs.forEach(log => {
log.events.forEach(evnt => {
if (evnt.type == "withdraw_rewards") {
evnt.attributes.forEach(attr => {
if (attr.key == "amount") {
withdrawnAmounts.push(attr);
}
})
}
})
})
});
return withdrawnAmounts;
}
The code helps me to get what I need, but I was wondering if there is a better way to write my code so that I dont have to use so many nested .forEach methods. I was wondering if I should use .flat() or .flatMap() but I'm curious to know how would people approach this?
Thank you!

You are going to have to call some kind of iteration for each level you're going deeper.
Now, there is a more functional way to get the desired data, using flatMap and filter:
const data = { "tx_responses": [{ "logs": [{ "events": [{ "type": "coin_received", "attributes": [{ "key": "receiver", "value": "somesome" }, { "key": "amount", "value": "somesome" }]}, { "type": "transfer", "attributes": [{ "key": "recipient", "value": "somesome" }, { "key": "sender", "value": "somesome" }, { "key": "amount", "value": "somesome" }]}, { "type": "withdraw_rewards", "attributes": [{ "key": "amount", "value": "somesomesomehere" }, { "key": "validator", "value": "somesome" }]}]}]}]};
const result = data.tx_responses
.flatMap(r => r.logs
.flatMap(l => l.events.filter(e => e.type === 'withdraw_rewards')
.flatMap(e => e.attributes.filter(a => a.key === 'amount'))
)
);
console.log(result);

How to change key name of an object by comparing another object?

I have an array of object and another object containing labels, how to write a simple function to compare both array and replace the key name.
input = [
{
"id": "AAP",
"prd": "PL",
"trcode": "NORTH",
"accountNo": "12345",
"prBranch": null,
"prDealer": "Dealer 1",
"prUser": "CFG",
"staticBranch": "YES",
"staticCustomer": "NO",
"reason": "Invalid request"
},
{
"id": "AAC",
"prd": "PL",
"trcode": "WEST",
"accountNo": "67890",
"prBranch": null,
"prDealer": "Dealer 2",
"prUser": "DFG",
"staticBranch": "YES",
"staticCustomer": "NO",
"reason": "Invalid request"
}
],
labels = [
{
"key": "id",
"value": "USER"
},
{
"key": "prd",
"value": "PRODUCT"
},
{
"key": "trcode",
"value": "TRANSFER_CODE"
},
{
"key": "accountNo",
"value": "ACCOUNT_NUMBER"
},
{
"key": "prBranch",
"value": "PROCESSING_BRANCH"
},
{
"key": "prDealer",
"value": "PROCESSING_DEALER"
},
{
"key": "prUser",
"value": "PROCESSING_USER"
},
{
"key": "staticBranch",
"value": "STATIC_BRANCH"
},
{
"key": "staticAgent",
"value": "STATIC_AGENT"
},
{
"key": "reason",
"value": "Reason"
}
]
Expected output =
[
{
"USER": "AAP",
"PRODUCT": "PL",
"TRANSFER_CODE": "NORTH",
"ACCOUNT_NUMBER": "12345",
"PROCESSING_BRANCH": null,
"PROCESSING_DEALER": "Dealer 1",
"PROCESSING_USER": "CFG",
"STATIC_BRANCH": "YES",
"STATIC_CUSTOMER": "NO",
"Reason": "Invalid request"
},
{
"USER": "AAC",
"PRODUCT": "PL",
"TRANSFER_CODE": "WEST",
"ACCOUNT_NUMBER": "67890",
"PROCESSING_BRANCH": null,
"PROCESSING_DEALER": "Dealer 2",
"PROCESSING_USER": "DFG",
"STATIC_BRANCH": "YES",
"STATIC_CUSTOMER": "NO",
"Reason": "Invalid request"
}
],

You can use Array#map to convert each object in the array. For each object, we can map over the entries of the object and use Array#find to look for the replacement key if it exists. Finally, Object.fromEntries converts the array of key-value pairs back to an object.
let input=[{id:"AAP",prd:"PL",trcode:"NORTH",accountNo:"12345",prBranch:null,prDealer:"Dealer 1",prUser:"CFG",staticBranch:"YES",staticCustomer:"NO",reason:"Invalid request"},{id:"AAC",prd:"PL",trcode:"WEST",accountNo:"67890",prBranch:null,prDealer:"Dealer 2",prUser:"DFG",staticBranch:"YES",staticCustomer:"NO",reason:"Invalid request"}],labels=[{key:"id",value:"USER"},{key:"prd",value:"PRODUCT"},{key:"trcode",value:"TRANSFER_CODE"},{key:"accountNo",value:"ACCOUNT_NUMBER"},{key:"prBranch",value:"PROCESSING_BRANCH"},{key:"prDealer",value:"PROCESSING_DEALER"},{key:"prUser",value:"PROCESSING_USER"},{key:"staticBranch",value:"STATIC_BRANCH"},{key:"staticAgent",value:"STATIC_AGENT"},{key:"reason",value:"Reason"}];
const res = input.map(o =>
Object.fromEntries(Object.entries(o)
.map(([k,v])=>[labels.find(({key})=>key===k)?.value ?? k, v])));
console.log(res)
.as-console-wrapper{max-height:100%!important;top:0}

Loop through input and inside the loop use a for...in loop to loop through each property.
Inside the loop, loop through labels and get the corresponding value to that property, set the value of the property to the new property and delete the previous property.
input.forEach(e => {
for (const l in e) {
var a;
labels.forEach(e => {
e.key == l && (a = e.value)
}), e[a] = e[l], delete e[l]
}
});
Demo:
input=[{id:"AAP",prd:"PL",trcode:"NORTH",accountNo:"12345",prBranch:null,prDealer:"Dealer 1",prUser:"CFG",staticBranch:"YES",staticCustomer:"NO",reason:"Invalid request"},{id:"AAC",prd:"PL",trcode:"WEST",accountNo:"67890",prBranch:null,prDealer:"Dealer 2",prUser:"DFG",staticBranch:"YES",staticCustomer:"NO",reason:"Invalid request"}];var labels=[{key:"id",value:"USER"},{key:"prd",value:"PRODUCT"},{key:"trcode",value:"TRANSFER_CODE"},{key:"accountNo",value:"ACCOUNT_NUMBER"},{key:"prBranch",value:"PROCESSING_BRANCH"},{key:"prDealer",value:"PROCESSING_DEALER"},{key:"prUser",value:"PROCESSING_USER"},{key:"staticBranch",value:"STATIC_BRANCH"},{key:"staticAgent",value:"STATIC_AGENT"},{key:"reason",value:"Reason"}];
input.forEach(e=>{for(const l in e){var a;labels.forEach(e=>{e.key==l&&(a=e.value)}),e[a]=e[l],delete e[l]}});
console.log(input);

One of the first thing I would to is to use an object instead of an array for your key association:
labels = {
"id": "USER",
"prd": "PRODUCT",
"trcode": "TRANSFER_CODE",
"accountNo": "ACCOUNT_NUMBER",
"prBranch": "PROCESSING_BRANCH",
"prDealer": "PROCESSING_DEALER",
"prUser": "PROCESSING_USER",
"staticBranch": "STATIC_BRANCH",
"staticAgent": "STATIC_AGENT",
"reason": "Reason"
}
Now if you want to map them to your new object you can do
function renameKeys(src) {
let entries = Object.entries(src)
let renamedEntries = entries.map(([key, value]) => [
labels[key] || key,
/* I added a fallback to the original key
if it's not found to avoid undefined keys */
value,
])
return Object.fromEntries(renamedEntries)
}
// and use it like so
console.log(input.map(renameKeys))

You can just iterate them and assign the values as below
for (var object of input) {
for (var mapping of labels) {
if (object[mapping.key] !== undefined) {
object[mapping.value] = object[mapping.key];
delete object[mapping.key];
}
}
}
console.log(input);

The way I'd do it would be:
const input = [{
"id": "AAP",
"prd": "PL",
"trcode": "NORTH",
"accountNo": "12345",
"prBranch": null,
"prDealer": "Dealer 1",
"prUser": "CFG",
"staticBranch": "YES",
"staticCustomer": "NO",
"reason": "Invalid request"
},
{
"id": "AAC",
"prd": "PL",
"trcode": "WEST",
"accountNo": "67890",
"prBranch": null,
"prDealer": "Dealer 2",
"prUser": "DFG",
"staticBranch": "YES",
"staticCustomer": "NO",
"reason": "Invalid request"
}
];
const labels = [{
"key": "id",
"value": "USER"
},
{
"key": "prd",
"value": "PRODUCT"
},
{
"key": "trcode",
"value": "TRANSFER_CODE"
},
{
"key": "accountNo",
"value": "ACCOUNT_NUMBER"
},
{
"key": "prBranch",
"value": "PROCESSING_BRANCH"
},
{
"key": "prDealer",
"value": "PROCESSING_DEALER"
},
{
"key": "prUser",
"value": "PROCESSING_USER"
},
{
"key": "staticBranch",
"value": "STATIC_BRANCH"
},
{
"key": "staticAgent",
"value": "STATIC_AGENT"
},
{
"key": "reason",
"value": "Reason"
}
]
// 1. create an object mapping the old labels to the new ones
const betterLabels = labels.reduce((outObj, item) => {
outObj[item.key] = item.value;
return outObj;
}, {});
// 2. use `Array.prototype.map` to traverse the input array
// and `Array.prototype.reduce` with the label mapping object
// to generate the output array
const output = input.map(item => {
return Object.entries(item).reduce((newItem, [key, value]) => {
betterLabels[key]
? newItem[betterLabels[key]] = value
: newItem[key] = value
return newItem
}, {});
});
//test
console.log(output);

Look up values in an array using looping forEach Google Apps Script Javascript

I have an object that looks like the following {key: id numbers}
var obj = {
"c4ecb": {id: [3]},
"a4269": {id: [34,36]},
"d76fa": {id: [54,55,60,61]},
"58cb5": {id: [67]}
}
How do I loop each above id in the following array, and return the label?
var response =
{
"success": true,
"data": [
{
"key": "c4ecb",
"name": "fruits",
"options": [
{
"label": "strawberry",
"id": 3
},
{
"label": "apple",
"id": 4
},
{
"label": "pineapple",
"id": 5
},
{
"label": "Other",
"id": 31
}
],
}
]
},
{
"success": true,
"data": [
{
"key": "a4269",
"name": "vegetables",
"options": [
{
"label": "lettuce",
"id": 34
},
{
"label": "cucumber",
"id": 35
},
{
"label": "radish",
"id": 36
}
],
}
]
},
{
"success": true,
"data": [
{
"key": "d76fa",
"name": "pasta",
"options": [
{
"label": "spaghetti",
"id": 54
},
{
"label": "rigatoni",
"id": 55
},
{
"label": "linguine",
"id": 56
},
{
"label": "lasagna",
"id": 60
},
{
"label": "fettuccine",
"id": 61
}
],
}
]
}
Finally, what I want to do is look up the key and return a string of id values.
For example, input c4ecb and output strawberry. Input a4269 and output lettuce, radish. Input d76fa and output "spaghetti, rigatoni, lasagna, fettuccine"
I think to join the multiple labels output into one string I could use something like
array.data.vegetables.map(vegetables => vegetables.value).join(', ')].toString();
So in the end I want to have something like
var fruits = [some code that outputs "strawberry"];
var vegetables = [some code that outputs "lettuce, radish"];
var pasta = [some code that outputs "spaghetti, rigatoni, lasagna, fettuccine"];
What I've tried so far:
The following loop will return the id only if there is one id to be called for: e.g. only in case one where {id: 3} but returns null in cases like {id: 34,36} (because it's looking for '34,36' in id, which doesn't exist - I need to look for each one individually.
response.data.forEach(({key, options}) => {
if (obj[key]) {
options.forEach(({id, label}) => {
if (id == obj[key].id) obj[key].label = label;
});
}
});
console.log(obj)

Filter the response object to focus on the category that matches the id.
Map over the options array and select the items which appear in obj[id].
Finally convert the filtered results to a string.
See filteredLabelsAsString() function below for implementation.
var obj = {
"c4ecb": {"id": [3]},
"a4269": {"id": [34,36]},
"d76fa": {"id": [54,55,60,61]},
"58cb5": {"id": [67]}
}
var response =
[{
"success": true,
"data": [
{
"key": "c4ecb",
"name": "fruits",
"options": [
{
"label": "strawberry",
"id": 3
},
{
"label": "apple",
"id": 4
},
{
"label": "pineapple",
"id": 5
},
{
"label": "Other",
"id": 31
}
],
}
]
},
{
"success": true,
"data": [
{
"key": "a4269",
"name": "vegetables",
"options": [
{
"label": "lettuce",
"id": 34
},
{
"label": "cucumber",
"id": 35
},
{
"label": "radish",
"id": 36
}
],
}
]
},
{
"success": true,
"data": [
{
"key": "d76fa",
"name": "pasta",
"options": [
{
"label": "spaghetti",
"id": 54
},
{
"label": "rigatoni",
"id": 55
},
{
"label": "linguine",
"id": 56
},
{
"label": "lasagna",
"id": 60
},
{
"label": "fettuccine",
"id": 61
}
],
}
]
}];
function filteredLabelsAsString(obj_key, obj, content=response) {
// sanity check: obj must contain obj_key
if (Object.keys(obj).includes(obj_key)) {
return content.filter((item) => {
// filter content using value of obj_key
return item.data[0].key == obj_key;
}).map((item) => {
// item : { success: true, data: [] }
// map over options array
return item.data[0].options.map((opt) => {
// option : {id, label}
// return the label if the id is in the obj object's list
if (obj[item.data[0].key].id.includes(opt.id))
return opt.label;
}).filter((label) => {
// filter out empty items
return label !== undefined;
});
}).join(",");
}
// if obj does not contain obj_key return empty string
return "";
}
console.log("fruits: " + filteredLabelsAsString("c4ecb", obj));
console.log("vegetables: " + filteredLabelsAsString("a4269", obj));
console.log("pasta: " + filteredLabelsAsString("d76fa", obj));

Need help formatting array in JavaScript

I have a JavaScript array with the following format:
[
{
"header": true,
"id": "0",
"name": "dairy",
},
{
"category": "dairy",
"header": false,
"id": "-LSlje6ESGALGpckMhb7",
"name": "milk",
},
{
"category": "dairy",
"header": false,
"id": "-LSm9EpFg5DhW036aUle",
"name": "cheese",
},
{
"header": true,
"id": "3",
"name": "dessert",
},
{
"category": "dessert",
"header": false,
"id": "-LSm9MLZkrnvtPySw5U6",
"name": "cake",
},
{
"category": "dessert",
"header": false,
"id": "-LSmAQ0rdDLrpz0TSPuD",
"name": "pie",
},
{
"header": true,
"id": "6",
"name": "fruit",
},
{
"category": "fruit",
"header": false,
"id": "-LSlazVIGAKLakxAIa8G",
"name": "apple",
},
{
"category": "fruit",
"header": false,
"id": "-LSlb5GH6xZz-DpNVS22",
"name": "pear",
},
{
"category": "fruit",
"header": false,
"id": "-LSwWJldY1nxQrotyv-V",
"name": "strawberry",
},
{
"header": true,
"id": "10",
"name": "meat",
},
{
"category": "meat",
"header": false,
"id": "-LSljXQzfXthJbOA54Ah",
"name": "fish",
},
{
"category": "meat",
"header": false,
"id": "-LSmA2-R9pOY8abAUyST",
"name": "steak",
},
{
"category": "meat",
"header": false,
"id": "-LSmAJ4J4gIfVQ8sgPDa",
"name": "pork",
},
]
What I am trying to do, is map through this array, and transform it to the following format:
[
{
title: nameOfFirstHeader,
data: items.slice(indexOfFirstHeader, indexOfSecondHeader),
},
{
title: nameOfSecondHeader,
data: items.slice(indexOfSecondHeader, indexOfThirdHeader),
},
{
title: nameOfThirdHeader,
data: items.slice(indexOfThirdHeader, indexOfFourthHeader),
},...and so on
]
So basically there will be an object section for each 'header' that is found in the original array. Each object section data property will contain the items found between the first header and the second header, and so on, until there are no more headers. I really can't wrap my head around how I can do this. Here is a reference to the the module I am using: https://github.com/saleel/react-native-super-grid#sectiongrid-example
Thanks!

I think this may be what you're trying to accomplish...
var grouped = items.reduce((acc,obj)=>{
let {header, name} = obj;
if (header) return [...acc, { title:name, data:[] }] // either first matching header or new match. Add fresh 'header' object
if (!acc.length) return acc; //not header and none have passed. Do nothing
let allButLast = acc.slice(0, acc.length-1),
lastElem = acc[acc.length-1]; // not a header, but there is an existing match. Add it to last match's data array
return [
...allButLast,
{
...lastElem,
data:[...lastElem.data, obj]
}
]
},[])
but it seems unreliable to trust the order of an array for this purpose. It would probably be more reliable to match by isHeader.name === notHeader.category to be less presumptive about the order of data you're iterating over. Like this...
var grouped = items.reduce((acc,obj)=>{
let {header, name, category} = obj;
if (header) return [...acc, { title:name, data:[] }];
if (!acc.length) return acc;
return acc.map((elem)=>{
if (elem.title !== category) return elem;
return {
...elem,
data: [ ...elem.data, obj]
};
})
},[])

I think you can probably do something like
const data = [];
let activeIndexForData = -1;
for(let i = 0; i < dataToSort.length -1; i++) {
if(dataToSort[i].header) {
activeIndexForData++;
}
if(data.length < activeIndexForData - 1) {
data.push({ title: dataToSort[i].name, data# []})
}
else {
data[activeIndexForData].data.push({ title: dataToSort[i].name, data: [])
}
}

Filter method on multidimensional array

I have an id and i to filter a multidimensional array with these. My code is:
service.fakedata.map(f=>{
f.results.map(r=>{
r = r.filter(m=> m.rId !== id)
})
})
and my array is :
"services": [
{
"id": "1839f72e-fa73-47de-b119-49fb971a5730",
"name": "In I/O Route",
"url": "http://wwww.in.io/[param1]/[param2]",
"inputParams": [
{
"id": "e74a6229-4c08-43a1-961f-abeb887fa90e",
"name": "in1",
"datatype": "string"
},
{
"id": "e74a6229-4c08-43a1-961f-abeb887fa90o",
"name": "in2",
"datatype": "string"
}
],
"isArrayResult": false,
"results": [
{
"id": "ef7c98db-9f12-45a8-b3fb-7d09a82abe3d",
"name": "out1",
"datatype": "string",
"fakedatatype": [
"address",
"city"
]
},
{
"id": "9b178ded-af27-43df-920f-daab5ad439b9",
"name": "out2",
"datatype": "string",
"fakedatatype": [
"internet",
"url"
]
}
],
"routeParameters": [
"param1",
"param2"
],
"fakedata": [
{
"id": "b0376694-9612-43d2-93ed-c74264df962e",
"url": "http://wwww.in.io/wood/good",
"params": [
{
"key": "param1",
"value": "wood"
},
{
"key": "param2",
"value": "good"
}
],
"inputParams": [
{
"iId":"e74a6229-4c08-43a1-961f-abeb887fa90e",
"key": "in1",
"value": "m"
},
{
"iId":"e74a6229-4c08-43a1-961f-abeb887fa90o",
"key": "in2",
"value": "z"
}
],
"results": [
{
"rId": "ef7c98db-9f12-45a8-b3fb-7d09a82abe3d",
"key": "out1",
"value": "result1",
"fakedatatype": [
"address",
"city"
]
},
{
"rId": "9b178ded-af27-43df-920f-daab5ad439b9",
"key": "out2",
"value": "result2",
"fakedatatype": [
"internet",
"url"
]
}
]
}
]
}
]
In this case filter is working (when I check with console.log) but it doesn't change fakedata array.
What was wrong with my code?

From https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/map
The map() method creates a new array with the results of calling a provided function on every element in the calling array.

base on #H77 suggestion i change my code and now my code is look like this and everything work well
const s = service.fakedata.map(f=>{
f.results = f.results.map(r=>{
return r.filter(m=> m.rId !== id)
})
})