Develop Reference

How do you check if value exist in object of object's array?

I want to know which logic i should use to check every object's array of parent object contained in grand parent object
Hi guys i want to check if this value for example : "127.0.0.1" exists in this object (MyObject has like 2k objects in it)
{
"name" : MyObject
"value": [
{
"name" : "Object1",
"properties":{
"address" : [
"13.65.25.19/32",
"13.66.60.119/32",
]
}
},
{
"name" : "Object2",
"properties":{
"address" : [
"13.65.25.19/32",
"127.0.0.1",
]
}
}
]
}
Btw does include() needs to match the whole string or for example if 127.0.0.1 is like this in my object 127.0.0.1/32, i can still retrieve it even if there is a ip range ?

Your data is structured quite specifically, so you can write a custom method which you can call over and over again. It will check for a
const obj = {
name: 'MyObject',
value: [
{
name: 'Object1',
properties: {
address: ['13.65.25.19/32', '13.66.60.119/32'],
},
},
{
name: 'Object2',
properties: {
address: ['13.65.25.19/32', '127.0.0.1'],
},
},
],
};
const address = '127.0.0.1';
const includesAddress = (address) => {
for (const val of obj.value) {
if (val.properties.address.some((a) => address === a)) return true;
}
return false;
};
console.log(includesAddress(address));

Array.flatMap implementation
const obj = {
name: 'MyObject',
value: [
{
name: 'Object1',
properties: {
address: ['13.65.25.19/32', '13.66.60.119/32'],
},
},
{
name: 'Object2',
properties: {
address: ['13.65.25.19/32', '127.0.0.1'],
},
},
],
};
const address = '127.0.0.1';
const output = obj.value.flatMap(item => item.properties.address).includes(address);
console.log(output);
If you want check if the partial ip addess is included in the list, you should make use of a regex implementation.
Sample Implementation
const obj = {
name: 'MyObject',
value: [
{
name: 'Object1',
properties: {
address: ['13.65.25.19/32', '13.66.60.119/32'],
},
},
{
name: 'Object2',
properties: {
address: ['13.65.25.19/32', '127.0.0.1'],
},
},
],
};
const address = '13.65.25.19';
const regex = new RegExp(address, 'i')
const output = obj.value.flatMap(item => item.properties.address).filter(x => regex.test(x)).length > 0;
console.log(output);

Reduce function wrapping data in an array

I have a reduce function that formats my data in the way i need but the only issue is the data is nested inside an array. I need to remove the outter array or just stop the reduce function from adding it in but every attempt Ive made to stop the reducer from wrapping the data in an array breaks my code. Ideally I would like my reducer to not wrap the data in an array but if thats not possible removing the array i need from inside the reducer cleanly seems like the only solution:
my data looks like this:
{
count: 4,
datapoints: [
{
Date: "2021-05-05",
score: 0,
},
{
Date: "2021-05-12",
score: 0,
},
{
Date: "2021-05-30",
score: 0,
},
{
Date: "2021-06-03",
score: 114,
},
],
};
my reducer function and api call:
const riskScores = await api.PCC.riskAssessment(userID, startdate, endDate);
const riskScoresFormatted = riskScores.datapoints.reduce((result, data) => {
const scores = result["riskAssessment"] || [];
scores.push({
value: data.score,
unit: "none",
recordedDate: data.Date,
method: "none",
type: "riskAssessment",
});
result["riskAssessment"] = scores;
return result;
}, []);
the output:
[riskAssessment: [{…}, {…}, {…}, {…}] ]
Ive tried just using the index of riskScoresFormatted[0] that comes back undefined. riskScoresFormatted.slice(1) just returns an empty array. Ive also tried targeting the first Item like riskScoresFormatted.riskAssessment this works but the value is sometimes null so it causes bugs later down the line.

Try changing the final reduce argument from [] to {} and I think you'll have better luck.
const riskScoresFormatted = riskScores.datapoints.reduce((result, data) => {
const scores = result["riskAssessment"] || [];
scores.push({
value: data.score,
unit: "none",
recordedDate: data.Date,
method: "none",
type: "riskAssessment",
});
result["riskAssessment"] = scores;
return result;
}, {});
Or, use Array.map() instead:
const riskScores = {
count: 4,
datapoints: [{
Date: "2021-05-05",
score: 0,
},
{
Date: "2021-05-12",
score: 0,
},
{
Date: "2021-05-30",
score: 0,
},
{
Date: "2021-06-03",
score: 114,
},
],
};
var riskScoresFormatted = riskScores.datapoints.map((data) => ({
value: data.score,
unit: "none",
recordedDate: data.Date,
method: "none",
type: "riskAssessment",
}));
console.log(riskScoresFormatted);

Javascript - Update object in array by id and move it to the first index

I have this array:
const chats = [
{ id: "chat-1", msg: { text: "World", date: (a date) } },
{ id: "chat-2", msg: { text: "Hello", date: (a date) } },
];
After receiving updates from my database, I receive this object:
// The second chat with update data
{ id: "chat-2", msg: { text: "Bye", date: (a date) } },
How can I (using ES6) replace the chat object from the original chats array and move it to the first index?
For now, I am doing this, but I am looking for a fastest way (smaller O)
// Get the modified chat
const modifiedChat = response.data;
// Search the modified chat in the chats array by id
const chatIndex = chats.findIndex(
(chat) => chat.id === modifiedChat.id
);
// Finally, using spread syntax, add the updated chat to the head of our current chats array
chats = [
modifiedChat,
...chats.slice(0, chatIndex),
...chats.slice(chatIndex + 1),
];

You can do the following,
const chats = [
{ id: "chat-1", msg: { text: "World", date: '' } },
{ id: "chat-2", msg: { text: "Hello", date: '' } },
];
const modifiedChat = { id: "chat-2", msg: { text: "Bye", date: '' } };
const newChats = [modifiedChat, ...chats.filter(item => item.id !== modifiedChat.id)];
console.log(newChats);

You can do something similar to how LRU cache works. You can now access every chat in O(1)

JavaScript, looping, and functional approach

Data Structure coming back from the server
[
{
id: 1,
type: "Pickup",
items: [
{
id: 1,
description: "Item 1"
}
]
},
{
id: 2,
type: "Drop",
items: [
{
id: 0,
description: "Item 0"
}
]
},
{
id: 3,
type: "Drop",
items: [
{
id: 1,
description: "Item 1"
},
{
id: 2,
description: "Item 2"
}
]
},
{
id: 0,
type: "Pickup",
items: [
{
id: 0,
description: "Item 0"
},
{
id: 2,
description: "Item 2"
}
]
}
];
Each element represents an event.
Each event is only a pickup or drop.
Each event can have one or more items.
Initial State
On initial load, loop over the response coming from the server and add an extra property called isSelected to each event, each item, and set it as false as default. -- Done.
This isSelected property is for UI purpose only and tells user(s) which event(s) and/or item(s) has/have been selected.
// shove the response coming from the server here and add extra property called isSelected and set it to default value (false)
const initialState = {
events: []
}
moveEvent method:
const moveEvent = ({ events }, selectedEventId) => {
// de-dupe selected items
const selectedItemIds = {};
// grab and find the selected event by id
let foundSelectedEvent = events.find(event => event.id === selectedEventId);
// update the found event and all its items' isSelected property to true
foundSelectedEvent = {
...foundSelectedEvent,
isSelected: true,
items: foundSelectedEvent.items.map(item => {
item = { ...item, isSelected: true };
// Keep track of the selected items to update the other events.
selectedItemIds[item.id] = item.id;
return item;
})
};
events = events.map(event => {
// update events array to have the found selected event
if(event.id === foundSelectedEvent.id) {
return foundSelectedEvent;
}
// Loop over the rest of the non selected events
event.items = event.items.map(item => {
// if the same item exists in the selected event's items, then set item's isSelected to true.
const foundItem = selectedItemIds[item.id];
// foundItem is the id of an item, so 0 is valid
if(foundItem >= 0) {
return { ...item, isSelected: true };
}
return item;
});
const itemCount = event.items.length;
const selectedItemCount = event.items.filter(item => item.isSelected).length;
// If all items in the event are set to isSelected true, then mark the event to isSelected true as well.
if(itemCount === selectedItemCount) {
event = { ...event, isSelected: true };
}
return event;
});
return { events }
}
Personally, I don't like the way I've implemented the moveEvent method, and it seems like an imperative approach even though I'm using find, filter, and map.
All this moveEvent method is doing is flipping the isSelected flag.
Is there a better solution?
Is there a way to reduce the amount of looping? Maybe events should be an object and even its items. At least, the lookup would be fast for finding an event, and I don't have to use Array.find initially. However, I still have to either loop over each other non selected events' properties or convert them back and forth using Object.entries and/or Object.values.
Is there more a functional approach? Can recursion resolve this?
Usage and Result
// found the event with id 0
const newState = moveEvent(initialState, 0);
// Expected results
[
{
id: 1,
type: 'Pickup',
isSelected: false,
items: [ { id: 1, isSelected: false, description: 'Item 1' } ]
}
{
id: 2,
type: 'Drop',
// becasue all items' isSelected properties are set to true (even though it is just one), then set this event's isSelected to true
isSelected: true,
// set this to true because event id 0 has the same item (id 1)
items: [ { id: 0, isSelected: true, description: 'Item 0' } ]
}
{
id: 3,
type: 'Drop',
// since all items' isSelected properties are not set to true, then this should remain false.
isSelected: false,
items: [
{ id: 1, isSelected: false, description: 'Item 1' },
// set this to true because event id 0 has the same item (id 2)
{ id: 2, isSelected: true, description: 'Item 2' }
]
}
{
id: 0,
type: 'Pickup',
// set isSelected to true because the selected event id is 0
isSelected: true,
items: [
// since this belongs to the selected event id of 0, then set all items' isSelected to true
{ id: 0, isSelected: true, description: 'Item 0' },
{ id: 2, isSelected: true, description: 'Item 2' }
]
}
]

One of the problems with the current solution is data duplication. You are basically trying to keep the data between the different items in sync. Instead of changing all items with the same id, make sure there are no duplicate items by using an approach closer to what you would find in a rational database.
Let's first normalize the data:
const response = [...]; // data returned by the server
let data = { eventIds: [], events: {}, items: {} };
for (const {id, items, ...event} of response) {
data.eventIds.push(id);
data.events[id] = event;
event.items = [];
for (const {id, ...item} of items) {
event.items.push(id);
data.items[id] = item;
}
}
This should result in:
const data {
eventIds: [1, 2, 3, 0], // original order
events: {
0: { type: "Pickup", items: [0, 2] },
1: { type: "Pickup", items: [1] },
2: { type: "Drop", items: [0] },
3: { type: "Drop", items: [1, 2] },
},
items: {
0: { description: "Item 0" },
1: { description: "Item 1" },
2: { description: "Item 2" },
},
};
The next thing to realize is that the isSelected property of an event is computed based on the isSelected property of its items. Storing this would mean more data duplication. Instead calculate it though a function.
const response = [{id:1,type:"Pickup",items:[{id:1,description:"Item 1"}]},{id:2,type:"Drop",items:[{id:0,description:"Item 0"}]},{id:3,type:"Drop",items:[{id:1,description:"Item 1"},{id:2,description:"Item 2"}]},{id:0,type:"Pickup",items:[{id:0,description:"Item 0"},{id:2,description:"Item 2"}]}];
// normalize incoming data
let data = { eventIds: [], events: {}, items: {} };
for (const {id, items, ...event} of response) {
data.eventIds.push(id);
data.events[id] = event;
event.items = [];
for (const {id, ...item} of items) {
event.items.push(id);
data.items[id] = item;
item.isSelected = false;
}
}
// don't copy isSelected into the event, calculate it with a function
const isEventSelected = ({events, items}, eventId) => {
return events[eventId].items.every(id => items[id].isSelected);
};
// log initial data
console.log(data);
for (const id of data.eventIds) {
console.log(`event ${id} selected?`, isEventSelected(data, id));
}
// moveEvent implementation with the normalized structure
const moveEvent = (data, eventId) => {
let { events, items } = data;
for (const id of events[eventId].items) {
items = {...items, [id]: {...items[id], isSelected: true}};
}
return { ...data, items };
};
data = moveEvent(data, 0);
// log after data applying `moveEvent(data, 0)`
console.log(data);
for (const id of data.eventIds) {
console.log(`event ${id} selected? `, isEventSelected(data, id));
}
// optional: convert structure back (if you still need it)
const convert = (data) => {
const { eventIds, events, items } = data;
return eventIds.map(id => ({
id,
...events[id],
isSelected: isEventSelected(data, id),
items: events[id].items.map(id => ({id, ...items[id]}))
}));
};
console.log(convert(data));
Check browser console, for better ouput readability.
I'm not sure if this answers solves your entire problem, but I hope you got something useful info out of it.

Updated nested object by matching ID

I have an array with nested objects that I need to update from another array of objects, if they match.
Here is the data structure I want to update:
const invoices = {
BatchItemRequest: [
{
bId: "bid10",
Invoice: {
Line: [
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10110" },
},
},
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "11110" },
},
Amount: 2499,
},
],
},
},
{
bId: "bid10",
Invoice: {
Line: [
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10110" },
},
},
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10111" },
},
Amount: 2499,
},
],
},
},
],
};
Here is the array of objects I want to update it from:
const accounts = [
{ AccountCode: "10110", Id: "84" },
{ AccountCode: "11110", Id: "5" },
{ AccountCode: "10111", Id: "81" },
];
I want to update invoices, using accounts, by inserting Id if AccountCode matches, to get the following structure:
const invoices = {
BatchItemRequest: [
{
bId: "bid10",
Invoice: {
Line: [
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10110", Id: "84" },
},
},
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "11110", Id: "5" },
},
Amount: 2499,
},
],
},
},
{
bId: "bid10",
Invoice: {
Line: [
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10110", Id: "84" },
},
},
{
SalesItemLineDetail: {
ItemAccountRef: { AccountCode: "10111", Id: "81" },
},
Amount: 2499,
},
],
},
},
],
};
I have tried various methods, such as the following:
const mapped = invoices.BatchItemRequest.map((item1) => {
return Object.assign(
item1,
accounts.find((item2) => {
return item2 && item1.Invoice.Line.ItemAccountRef.AccountCode === item2.AccountCode;
})
);
});
Problem with this approach (it doesn't work as I think I need to do another nested map), but it also creates a new array, only including the nested elements of invoices.
Does anyone know a good approach to this?

This isn't the cleanest of code but it gets the job done:
function matchInvoiceWithAccount(invoices, accounts) {
const mappedInvoices = invoices.BatchItemRequest.map((request) => {
// Shouldn't modify input parameter, could use Object.assign to create a copy and modify the copy instead for purity
request.Invoice.Line = request.Invoice.Line.map((line) => {
const accountCode = line.SalesItemLineDetail.ItemAccountRef.AccountCode;
// If accounts was a map of AccountCode to Id you would't need to search for it which would be more effective
const account = accounts.find((account) => account.AccountCode === accountCode);
if (account) {
line.SalesItemLineDetail.ItemAccountRef.Id = account.Id;
}
return line;
});
return request;
});
return {
BatchItemRequest: mappedInvoices,
};
}
What you could and probably should do to improve this is to not modify the input parameters of the function, but that requires that you in a better way copy the original, either using Object.assign or spread operator.

At first, it will be good to create Map from your accounts array. We will go one time for array with O(n) and then will read ids by code with O(1). And nested fors is O(m*n), that will be much more slower at big arrays.
const idsByAccountCodes = new Map();
accounts.forEach((data) => {
idsByAccountCodes.set(data.AccountCode, data.Id);
})
or shorter:
const idsByAccountCode = new Map(accounts.map((data) => [data.AccountCode, data.Id]))
then if you want to mutate original values you can go through all nesting levels and add values
for ( const {Invoice:{ Line: line }} of invoices.BatchItemRequest){
for ( const {SalesItemLineDetail: {ItemAccountRef: item}} of line){
item.Id = idsByAccountCodes.get(item.AccountCode) || 'some default value'
// also if you don't have ids for all codes you need to define logic for that case
}
}
If you don't need to mutate original big object "invoices" and all of nested objects, then you can create recursive clone of if with something like lodash.cloneDeep