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How to fix invalid JSON with RegExp in Javascript?

This is what I've tried
// input
let input = "{id: 1, name: apple, qty: 2, colors: [{id: 1, hex: #f95}], store: {id: 1, name: Apple Store}}"
let result = input.replace((/([\w]+)(:)/g), "\"$1\"$2");
// {"id": 1, "name": apple, "qty": 2, "colors": [{"id": 1, "hex": #f95}], "store": {"id": 1, "name": Apple Store}}
And then I just replace it like, replaceAll(': ', ': "'). I think it's not good practice to resolve it, may there is someone who can help me with this problem, thank you so much.

You can convert the stated string that looks almost like an object into an actual JavaScript object with the following assumptions:
keys are composed of alphanumeric and underscores chars
values are treated as numbers if they have the format of a number, e.g. an optional minus sign, followed by digits with optional .
values are treated as a string unless it has the form of a number, or start with [ (array) or { (object)
string values may not contain , or }
const input = "{id: 1, name: apple, qty: 2, colors: [{id: 1, hex: #f95}], store: {id: 1, name: Apple Store}}";
const regex1 = /([,\{] *)(\w+):/g;
const regex2 = /([,\{] *"\w+":)(?! *-?[0-9\.]+[,\}])(?! *[\{\[])( *)([^,\}]*)/g;
let json = input
.replace(regex1, '$1"$2":')
.replace(regex2, '$1$2"$3"')
let result = JSON.parse(json);
console.log(JSON.stringify(result, null, ' '));
Output:
{
"id": 1,
"name": "apple",
"qty": 2,
"colors": [
{
"id": 1,
"hex": "#f95"
}
],
"store": {
"id": 1,
"name": "Apple Store"
}
}
Explanation of regex1:
([,\{] *) -- capture group 1: , or {, followed by optional spaces
(\w+) -- capture group 2: 1+ word chars (alphanumeric and underscore)
: -- literal :
replace '$1"$2":' -- capture group 1, followed by capture group 2 enclosed in quotes, followed by colon
Explanation of regex2:
([,\{] *"\w+":) -- capture group 1: , or {, followed by optional spaces, quote, 1+ word chars, quote, colon
(?! *-?[0-9\.]+[,\}]) -- negative lookahead for optional spaces, a number, followed by , or }
(?! *[\{\[]) -- negative lookahead for optional spaces, followed by { or [
( *) -- capture group 2: optional spaces
([^,\}]*) -- capture group 3: everything that is not a , or }
replace '$1$2"$3"' -- capture group 1, followed by capture group 2, followed by capture group 3 enclosed in quotes
Learn more about regex: https://twiki.org/cgi-bin/view/Codev/TWikiPresentation2018x10x14Regex

Thanks for all answers, I tried this way and its works
class FixJson {
constructor() {
this.run = (json) => {
const fixDataType = (json) => {
for (const key in json) {
if (json.hasOwnProperty(key)) {
const value = json[key];
if (typeof value === 'object') {
fixDataType(value);
} else if (value === 'true' || value === 'false') {
json[key] = value === 'true';
} else if (!isNaN(value)) {
json[key] = Number(value);
}
}
}
return json;
}
// use the replace function to add double quotes around the property names
const fixedJson = json.replace(/([a-zA-Z0-9!##\$%\^\&*\)\(+=._-]+)/g, '"$1"');
// use the JSON.parse function to parse the fixed JSON string into a JavaScript object
const obj = JSON.parse(fixedJson.replaceAll('" "', ' '));
// fix json data type, and return the result
return fixDataType(obj)
}
}
}
const fix = new FixJson()
let result = fix.run("<your_invalid_json>")

Parsing text using regex javascript

guys i am stuck while parsing following text into object. I have created two separate regex but i want to make only one. Below i am posting sample text as well as my following regex pattern.
PAYER:\r\n\r\n MCNA \r\n\r\nPROVIDER:\r\n\r\n MY KHAN \r\n Provider ID: 115446397114\r\n Tax ID: 27222193992\r\n\r\nINSURED:\r\n\r\n VICTORY OKOYO\r\n Member ID: 60451158048\r\n Birth Date: 05/04/2008\r\n Gender: Male\r\n\r\nCOVERAGE TYPE:\r\n\r\n Dental Care
REGEX:
re = new RegExp('(.*?):\r\n\r\n(.*?)(?:\r\n|$)', 'g');
re2 = new RegExp('(.*?):(.*?)(?:\r\n|$)', 'g');
Expected result:
{
payer: 'MCNA',
provider: 'MY KHAN'
}

This turns your input into an object that contains all key/value pairs:
const input = 'PAYER:\r\n\r\n MCNA \r\n\r\nPROVIDER:\r\n\r\n MY KHAN \r\n Provider ID: 115446397114\r\n Tax ID: 27222193992\r\n\r\nINSURED:\r\n\r\n VICTORY OKO\r\n Member ID: 60451158048\r\n Birth Date: 05/04/2009\r\n Gender: Male\r\n\r\nCOVERAGE TYPE:\r\n\r\n Dental Care';
let result = Object.fromEntries(input
.replace(/([^:]+):\s+([^\n\r]+)\s*/g, (m, c1, c2) => c1.toLowerCase() + '\r' + c2 + '\n')
.split('\n')
.filter(Boolean)
.map(item => item.trim().split('\r'))
);
console.log(result);
Output:
{
"payer": "MCNA",
"provider": "MY KHAN",
"provider id": "115446397114",
"tax id": "27222193992",
"insured": "VICTORY OKO",
"member id": "60451158048",
"birth date": "05/04/2009",
"gender": "Male",
"coverage type": "Dental Care"
}
Explanation:
Object.fromEntries() -- convert a 2D array to object, ex: [ ['a', 1], ['b', 2] ] => {a: 1, b: 2}
.replace() regex /([^:]+):\s+([^\n\r]+)\s*/g -- two capture groups, one for key, one for value
replace action c1.toLowerCase() + '\r' + c2 + '\n' -- convert key to lowercase, separate key/value pairs with newline
.split('\n') -- split by newline
.filter(Boolean): -- remove empty items
.map(item => item.trim().split('\r')) -- change array item to [key, value], e.g. change flat array to 2D array
You could add one more filter after the .map() to keep only keys of interest.

How can I filter an array containing varied object structures dynamically?

My usage will contain 6 different object types (some which contain double nested arrays), and any possibility of number of entries, on the condition that an given entry is unique.
These objects do not have a consistent unique identifier (a unique identifier is applied in backend on submission).
here is an example of what the array may look like (only 2 object types):
arr = [
{name:"aaa",time:15},
{name:"aaa",time:22},
{timeline: "250", chars[{a},{b},{c}]},
{timeline: "220", chars[{d},{e},{f}]},
]
obj = {name:"aaa",time:22}
My intention is to gain a true or false based on if obj is inside arr
I have tried methods:
I was suggested this method & it errors: #<Object> is not a function
console.log(arr.find(obj))
I also found this suggestion but it will always return false even with the element present
console.log(arr.includes(object))
I tried this method myself, though it will always fail.
console.log(arr.filter((element, index) => element === obj)
With attempt 4, If I was to compare name, this would be insufficient as unique time would be ignored missing valid entries.
If I was to pass every field, this would also not work as each object may or may not have the field and cause error.
Its not really possible to manually pre-filter filter into distinct categories, as every time a new type is added it will need manually adding to the filter.
If there is a library which could do this that you know of, please let me know as that would be perfect. Otherwise any other suggestions (excluding separating arrays) Would be greatly appreciated.

Use arr.some() to check if the required object is present in the array.
To compare the objects, a simpler way is to Stringify both the Objects and compare them.
const arr = [
{name:"aaa",time:15},
{name:"aaa",time:22},
{name: "aaa", chars: ["a", "b", "c"]},
{name: "bbb", chars: ["d", "e", "f"]},
]
const obj1 = {name:"aaa", time: 15}
const obj2 = {name:"aaa",chars: ["a", "b", "c"]}
console.log(arr.some((element) => JSON.stringify(element) === JSON.stringify(obj1))) // true
console.log(arr.some((element) => JSON.stringify(element) === JSON.stringify(obj2))) // true
Didn't give much thought on performance.

I didn't put much thought on performace here but this might help:
function checkObjectInArray(arr, obj) {
const res = arr.some((el) => deepEqual(el, obj));
console.log(res);
}
function deepEqual(obj1, obj2) {
if (Object.keys(obj1).length !== Object.keys(obj2).length) return false;
for (let prop in obj1) {
if (!obj2.hasOwnProperty(prop) || obj2[prop] !== obj1[prop]) {
return false;
}
}
return true;
}
in your case you can use it like:
arr = [
{ name: "aaa", time: 15 },
{ name: "aaa", time: 22 },
{ timeline: "250", data: ["2", "3", "4"] },
{ timeline: "251", data: ["2", "3", "4"] }, // what is chars[{d},{e},{f}] ?!
];
obj = { name: "aaa", time: 22 };
checkObjectInArray(arr, obj);

Observation : arr is not a valid array. Nested chars is not containing a valid value.
Solution : You can simply achieve the requirement by Just converting the JSON object into a JSON string and by comparing.
This solution works fine as you are just trying to find a single object in the passed arr.
Live Demo :
const arr = [
{name:"aaa",time:15},
{name:"aaa",time:22},
{timeline: "250", chars: [{a: 1},{b: 2},{c: 3}]},
{timeline: "220", chars: [{d: 4},{e: 5},{f: 6}]},
];
const obj = {name:"aaa",time:22};
const res = JSON.stringify(arr).indexOf(JSON.stringify(obj)) !== -1 ? true : false;
console.log(res);

Split each element in array into object after certain character

I'm new to node.js and javascript. I have the following array:
var oldarray = [
'name1\tstreet\tperson\tphone1\tphone2\nname2\street2\tperson1\tphone82\tphone3\n'
]
Note, this is a single element array. First, I require the array to contain a new element after each new line first, then, re-format like below:
let headers = {
name: "",
street: "",
person: "",
phone 1 "",
phone 2 ""
}
How can I parse through each element (after creating a new element after each +), and assign an object within an array after each instance of \
The desired output is this:
[{
name: 'name1',
street: 'street2',
person: 'person1',
phone1: 'phone82 ',
phone2: 'phone3'
},
{
name: 'name2',
street: 'street2',
person: 'person1',
phone1: 'phone1 ',
phone2: 'phone2'
}]
Any help is highly appreciated.

If you have the same structure for all items in OLD_ARRAY you can use map, filter and reduce in order to manipulate your input.
So what I did?
In case that you have multiple strings like the example input (more than 1 array item) I convert it to sub-arrays of each string by using map and split by \n, which is your string separator. Than I filtered it by strings that are not empty (becasue that you have a post-fix of \n as well).
From each sub-array I extracted all the contacts using extractContacts function - it splites the sub-array by your separaotr, \t, and map it according to your contacts temaplte.
Since it's a format of array of arrays, I used reduce to concat all the arrays together
const OLD_ARRAY = [
'name1\tstreet\tperson\tphone1\tphone2\n' +
'name2\tstreet2\tperson1\tphone82\tphone3\n'
];
function extractContacts(templates) {
return templates.map(t => t.split('\t'))
.map(details => ({
name: details[0],
street: details[1],
person: details[2],
phone1: details[3],
phone2: details[4]
}));
}
let contacts = OLD_ARRAY.map(str => str.split('\n').filter(str => str !== ''))
.map(template => extractContacts(template))
.reduce((a, acc) => acc.concat(a), []);
console.log(contacts)

You can split each oldarray value on \n and then \t into newarray, and then use Object.fromEntries to build an object from each newarray value, combining the split values with each key from headers:
var oldarray = [
'name1\tstreet\tperson\tphone1\tphone2\n' +
'name2\tstreet2\tperson1\tphone82\tphone3\n'
]
let newarray = [];
oldarray.forEach(s => s.trim().split('\n').map(v => newarray.push(v.split('\t'))));
let headers = {
'name': "",
'street': "",
'person': "",
'phone 1': "",
'phone 2': ""
}
let keys = Object.keys(headers);
out = newarray.map(s => Object.fromEntries(s.map((v, i) => [keys[i], v])));
console.log(out);

First split the array by \n to get individual paths and then split them by \t, and use reduce to create new header objects from each subarray
var oldarray = [
'name1\tstreet\tperson\tphone1\tphone2\n' +
'name2\tstreet2\tperson1\tphone82\tphone3\n' +
'name4\tstreet4\tperson4\tphone84\tphone4\n'
]
arr = oldarray.flatMap(o => o.split("\n"))
c = arr.map(o => o.split("\t"))
c.pop()
result = c.reduce((acc,[name, street, person, phone1, phone2],i) => {
acc = [...acc,{name:name,street:street,person:person,phone1:phone1,phone2:phone2}]
return acc
},[])
console.log(result)

Regex for substring on NodeJS using pinch.js

I am modifying JSON files/Javascript object using Pinch library: https://github.com/Baggz/Pinch
In this example, pinch() with regex parameter /id/ modifies ALL the id values to 321.
What I want to do is be able to change the value of all ids but only for a specific "Requestor", based on a parameter (requestorToChange). Let's say "RequestorX". How do I write the regex for it?
var sample = {
"RequestorX":
[{
user: {
id: '123'
},
request: {
id: '456'
},
book: {
id: '789'
}
}],
"RequestorY":
[{
user: {
id: '111'
},
request: {
id: '222'
},
book: {
id: '333'
}
}]
};
const requestorToChange = 'RequestorX'
pinch(sample, /id/, function(path, key, value) {
return '321';
});
console.log(JSON.stringify(sample))
I know that one option is to just do:
pinch(sample['RequestorX'], /id/, function(path, key, value) {
return '321';
});
But I need to be able to do it via the regex field since in reality, I will be manipulating deeply nested JSON files.

The explanation on the GitHub page is a bit sparse, but basically you start with the dot notation replacement style and replace the variable parts with regex patterns whilst adhering to the rules of JS regular expressions.
So, in your case, a dot notation pattern 'RequestorX[0].user.id'
becomes a regex like /RequestorX\[0\]\.(user|request|book)\.id/
Somes notes:
first we have to escape the square brackets because those have special meaning in regex
next, we also have to escape the . to use it as dot notation symbol
we use a group with alternations to replace the id on all of them
I tried to use new RegExp instead of the /../ notation to create a regex Object to add your constant to the pattern, unfortunately only the first item is replaced in this case, probably a bug...
pinch(sample, new RegExp(requestorToChange +'\[0\]\.(user|request|book)\.id'), '321');
Sample code (the SO code snippet outputs some extra gibberish about RequestorY, ignore it)
var sample = {
"RequestorX": [
{
"user": {
"id": "123"
},
"request": {
"id": "456"
},
"book": {
"id": "789"
}
}
],
"RequestorY": [
{
"user": {
"id": "123"
},
"request": {
"id": "456"
},
"book": {
"id": "789"
}
}
]
}
const requestorToChange = 'RequestorX';
//var result = pinch(sample, 'RequestorX[0].user.id', '321'); //replace the user id of RequestorX with dot notation
var result = pinch(sample, /RequestorX\[0\]\.(user|request|book)\.id/, '321');
//var result = pinch(sample, new RegExp(requestorToChange +'\[0\]\.(user|request|book)\.id'), '321');
console.log(JSON.stringify(result));
<script src="https://cdn.jsdelivr.net/npm/pinch#0.1.3/src/pinch.js"></script>
Alas, JSON + regex sounds a bit weird but the tool looks legit.