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Quotation marks shortage when from python dumping JSON and parse it within js2py environment

So please do not ask me why, but I would like to do the following.
I would like to define a javascript function as a string within a dictionary in the python language. Then I would like to execute this function in a browserless javascript environment. The defined function already contains two types of quotation marks.
My attempt so far:
import json
import js2py
js_function = """
var convertDateTime = function (s, key, input) {
console.log(' - Executing "convertDateTime".');
s[key] = input.dateTime.toISOString().split('Z')[0].replace('T', '');
};
"""
f = {'function': js_function}
result of f (which is not code...):
{'function': '\nvar convertDateTime = function (s, key, input) >{\n
console.log(\' - Executing "convertDateTime".\');\n
s[key] = input.dateTime.toISOString().split(\'Z\')[0].replace(\'T\', \'
\');\n};\n'}
Now, first of all, I would like to convert this to a string representing correct JSON and then convert it to a javascript object in the js2py environment. In order to let it work in js2py env with the JSON.parse I need to remove the \n, \" and ' marks. If I do not do it, I get the message:
js_env.execute("spec = JSON.parse('"+spec+"');")
JsException: SyntaxError: Could not parse JSON string - Invalid syntax
I tried every quotation combination with the JSON.parse there is and found this single working combination.
spec = json.dumps(f).replace("\\n", "").replace('\\"', "").replace("'", "`")
js_env = js2py.EvalJs()
js_env.execute("spec = JSON.parse('"+spec+"');")
The problem, however, is that when evaluating this function, js2py does not support ` and I couldn't find a way to let it work with js2py 6 stuff, because I couldn't find function in js2py which can create an environment supporting JavaScript 6.
js_env.execute("eval(spec['function'])")
Error message:
js_env.execute("eval(spec['function'])")
NotImplementedError: TemplateLiteral is not supported!
Restrictions:
The js function which can be anything, but will only contain simple
js code must end up as a string in a python dict somewhere.
I should be able to execute the js function in a browserless js
environment.
python version 2.7.13
I hope somebody could help me forward,

You can just do:
js_env.execute("spec = "+spec+";")
JSON stands for JavaScript Object Notation - the syntax originates from JS and valid JSON should automatically be valid JS. Therefore JSON can be directly inserted into JavaScript code and just work.

JSON Parsing error with backslash

I have been trying to figure out why the following JSON input will be failed to parse in JSON.parse function.
{"World":"Hello\\Test"}
The json above is being returned by JSON.NET.
I have tried multiple methods to get this working. As you can see the backslash is escaped and https://jsonlint.com/ is able to parse it.
I have a failing sample at https://jsfiddle.net/ckp0uc0p/3/ as well.
Any help will be appreciated.

The best way to inject JSON into JavaScript source code (when generating the JavaScript with a server side language), is to inject it directly where you need it, not inside a string literal that needs to be parsed.
For example:
var foo = <json blob>;
so that the result will be
var foo = {"World":"Hello\\Test"};
JavaScript will interpret this as an object literal resulting in an object, which is what you want to get anyway. This avoids all the problems with "nested" escape sequences.

You need to add two \\ for every backslash you want to have it displayed. If you're parsing a json, to display 2 backslashes you need to add 4.
// inside a string to be parsed as json
var json = '{"World":"Hello\\\\Test"}'
console.log(JSON.parse(json))
// directly in an object
var object = {"World": "Hello\\Test"}
console.log(object)

try
{
var res = '{"World":"Hello\\\\Test"}';
var s = JSON.parse(res);
console.log(JSON.stringify(s));
} catch(error) {
alert(error);
}

"Fixing" JSON coming out of MySQL

I'm fetching JSON code stored in MySQL and it has extra slashes, which I have to remove in order to parse it in JavaScript, after I print it on the page. Right now I'm doing the following:
$save = str_replace("\n", "<br>", $save); // Replace new line characters with <br>
$save = str_replace('\\"', '"', $save); // top-level JSON
$save = str_replace('\\\\"', '\"', $save); // HTML inside top level JSON
$save = str_replace('\\\\\\\\\\"', '\\\\\"', $save); // HTML inside second level JSON
Here is an example JSON code, as it comes out from MySQL:
{\"id\":2335,\"editor\":{\"selected_shape\":\"spot-7488\"},\"general\":{\"name\":\"HTML Test\",\"shortcode\":\"html-test\",\"width\":1280,\"height\":776},\"spots\":[{\"id\":\"spot-7488\",\"x\":9.9,\"y\":22.6,\"default_style\":{\"use_icon\":1},\"tooltip_content\":{\"content_type\":\"content-builder\",\"plain_text\":\"<p class=\\\"test\\\">Test</p>\",\"squares_json\":\"{\\\"containers\\\":[{\\\"id\\\":\\\"sq-container-293021\\\",\\\"settings\\\":{\\\"elements\\\":[{\\\"settings\\\":{\\\"name\\\":\\\"Paragraph\\\",\\\"iconClass\\\":\\\"fa fa-paragraph\\\"},\\\"options\\\":{\\\"text\\\":{\\\"text\\\":\\\"<p class=\\\\\\\"test\\\\\\\">Test</p>\\\"}}}]}}]}\"}}]}
And here is how it's supposed to look in order to get parsed correctly (using jsonlint.com to test):
{"id":2335,"editor":{"selected_shape":"spot-7488"},"general":{"name":"HTML Test","shortcode":"html-test","width":1280,"height":776},"spots":[{"id":"spot-7488","x":9.9,"y":22.6,"default_style":{"use_icon":1},"tooltip_content":{"content_type":"content-builder","plain_text":"<p class=\"test\">Test</p>","squares_json":"{\"containers\":[{\"id\":\"sq-container-293021\",\"settings\":{\"elements\":[{\"settings\":{\"name\":\"Paragraph\",\"iconClass\":\"fa fa-paragraph\"},\"options\":{\"text\":{\"text\":\"<p class=\\\"test\\\">Test</p>\"}}}]}}]}"}}]}
Please note that I have HTML code inside JSON, which is inside another JSON and this is where it gets a bit messy.
My question - is there a function or library for PHP (for JS will work too) which covers all those corner cases, because I'm sure someone will find a way to break the script.
Thanks!

The short answer, which is woefully inadequate, is for you to use stripslashes. The reason this answer is not adequate is that your JSON string might have been escaped or had addslashes called on it multiple times and you would have to call stripslashes precisely once for each time this had happened.
The proper solution is to find out where the slashes are being added and either a) avoid adding the slashes or b) understand why the slashes are there and respond accordingly. I strongly believe that the process that creates that broken JSON is where the problem lies.
Slashes are typically added in PHP in a few cases:
magic_quotes are turned on. This is an old PHP feature which has been removed. The basic idea is that PHP used to auto-escape quotes in incoming requests to let you just cram incoming strings into a db. Guess what? NOT SAFE.
add_slashes has been called. Why call this? Some folks use it as an incorrect means of escaping data before sticking stuff in a db. Others use it to keep HTML from breaking when echoing variables out (htmlspecialchars should probably be used instead). It can also come in handy in a variety of other meta situations when you are defining code in a string.
When escaping data input. The most common escaping function is mysqli_real_escape_string. It's very important to escape values before inserting them in a db to prevent sql injection and other exploits but you should never escape things twice.
So there's a possibility that your code is double-escaping things or that addslashes is getting called or something like magic_quotes is causing the problem, but I suspect it is another problem: some JS code might be supplying this JSON not as a proper JSON string, but one that has been escaped so to define a string within javascript.
If you take your example JSON string above, and slap some quotes around it:
var myJSON = "<put your string here>";
then SURPRISE your javascript is not broken and the var myJSON contains a string that is actually valid JSON and can be parsed into an a valid JSON object:
var myJSON = "{\"id\":2335,\"editor\":{\"selected_shape\":\"spot-7488\"},\"general\":{\"name\":\"HTML Test\",\"shortcode\":\"html-test\",\"width\":1280,\"height\":776},\"spots\":[{\"id\":\"spot-7488\",\"x\":9.9,\"y\":22.6,\"default_style\":{\"use_icon\":1},\"tooltip_content\":{\"content_type\":\"content-builder\",\"plain_text\":\"<p class=\\\"test\\\">Test</p>\",\"squares_json\":\"{\\\"containers\\\":[{\\\"id\\\":\\\"sq-container-293021\\\",\\\"settings\\\":{\\\"elements\\\":[{\\\"settings\\\":{\\\"name\\\":\\\"Paragraph\\\",\\\"iconClass\\\":\\\"fa fa-paragraph\\\"},\\\"options\\\":{\\\"text\\\":{\\\"text\\\":\\\"<p class=\\\\\\\"test\\\\\\\">Test</p>\\\"}}}]}}]}\"}}]}";
console.log(JSON.parse(myJSON)); // this is an actual object
The key here is to examine the point of entry where this JSON arrives in your system. I suspect some AJAX request has created some object and rather than sending valid JSON Of that object, it is sending instead an escaped string of a JSON object.
EDIT:
Here's a simple example of what happens when you have too many encodings. Try running this JS in your browser and observe the console output:
var myObj = {"key":"here is my value"};
console.log(myObj);
var myJSON = JSON.stringify(myObj);
console.log(myJSON);
var doubleEncoded = JSON.stringify(myJSON);
console.log(doubleEncoded);

remove double quotes from Json return data using Jquery

I use JQuery to get Json data, but the data it display has double quotes. It there a function to remove it?
$('div#ListingData').text(JSON.stringify(data.data.items[0].links[1].caption))
it returns:
"House"
How can I remove the double quote? Cheers.

Use replace:
var test = "\"House\"";
console.log(test);
console.log(test.replace(/\"/g, ""));
// "House"
// House
Note the g on the end means "global" (replace all).

For niche needs when you know your data like your example ... this works :
JSON.parse(this_is_double_quoted);
JSON.parse("House"); // for example

The stringfy method is not for parsing JSON, it's for turning an object into a JSON string.
The JSON is parsed by jQuery when you load it, you don't need to parse the data to use it. Just use the string in the data:
$('div#ListingData').text(data.data.items[0].links[1].caption);

Someone here suggested using eval() to remove the quotes from a string. Don't do that, that's just begging for code injection.
Another way to do this that I don't see listed here is using:
let message = JSON.stringify(your_json_here); // "Hello World"
console.log(JSON.parse(message)) // Hello World

I also had this question, but in my case I didn't want to use a regex, because my JSON value may contain quotation marks. Hopefully my answer will help others in the future.
I solved this issue by using a standard string slice to remove the first and last characters. This works for me, because I used JSON.stringify() on the textarea that produced it and as a result, I know that I'm always going to have the "s at each end of the string.
In this generalized example, response is the JSON object my AJAX returns, and key is the name of my JSON key.
response.key.slice(1, response.key.length-1)
I used it like this with a regex replace to preserve the line breaks and write the content of that key to a paragraph block in my HTML:
$('#description').html(studyData.description.slice(1, studyData.description.length-1).replace(/\\n/g, '<br/>'));
In this case, $('#description') is the paragraph tag I'm writing to. studyData is my JSON object, and description is my key with a multi-line value.

You can simple try String(); to remove the quotes.
Refer the first example here: https://www.w3schools.com/jsref/jsref_string.asp
Thank me later.
PS: TO MODs: don't mistaken me for digging the dead old question. I faced this issue today and I came across this post while searching for the answer and I'm just posting the answer.

What you are doing is making a JSON string in your example. Either don't use the JSON.stringify() or if you ever do have JSON data coming back and you don't want quotations, Simply use JSON.parse() to remove quotations around JSON responses! Don't use regex, there's no need to.

I dont think there is a need to replace any quotes, this is a perfectly formed JSON string, you just need to convert JSON string into object.This article perfectly explains the situation : Link
Example :
success: function (data) {
// assuming that everything is correct and there is no exception being thrown
// output string {"d":"{"username":"hi","email":"hi#gmail.com","password":"123"}"}
// now we need to remove the double quotes (as it will create problem and
// if double quotes aren't removed then this JSON string is useless)
// The output string : {"d":"{"username":"hi","email":"hi#gmail.com","password":"123"}"}
// The required string : {"d":{username:"hi",email:"hi#gmail.com",password:"123"}"}
// For security reasons the d is added (indicating the return "data")
// so actually we need to convert data.d into series of objects
// Inbuilt function "JSON.Parse" will return streams of objects
// JSON String : "{"username":"hi","email":"hi#gmail.com","password":"123"}"
console.log(data); // output : Object {d="{"username":"hi","email":"hi#gmail.com","password":"123"}"}
console.log(data.d); // output : {"username":"hi","email":"hi#gmail.com","password":"123"} (accessing what's stored in "d")
console.log(data.d[0]); // output : { (just accessing the first element of array of "strings")
var content = JSON.parse(data.d); // output : Object {username:"hi",email:"hi#gmail.com",password:"123"}" (correct)
console.log(content.username); // output : hi
var _name = content.username;
alert(_name); // hi
}

I had similar situation in a Promise just solved doing a cast as (String)
export async function getUserIdByRole(userRole: string): Promise<string> {
const getRole = userData.users.find((element) => element.role === userRole);
return String (getRole?.id);
}

How can I access JSON.#attribute from an XML Converted on Javascript

I got a JSON converted from XML.
So, how can I get json.#attribute.something.
# <-- this one will make javascript error
I use Javascript.

Making a great exercise of imagination, I suppose you've used jQuery to download some JSON through AJAX and you have an object with a key called "#attribute", such as this:
var foo = {
"#attribute": 33
}
You just need to use square brackets:
console.log(foo["#attribute"])