DiscordJS + NodeJS: SyntaxError: Unexpected end of JSON input at JSON.parse (<anonymous>) - node.js

Question

Having an issue where I will randomly get this error after about an hour of my code running.
SyntaxError: Unexpected end of JSON input
at JSON.parse (<anonymous>)
Here is my code:
function matchMaking() {
setInterval(function() {
fs.readFile('./rankedQueue.json', 'utf8', function(err, data) {
const file = JSON.parse(data); //The line the error occurs
if (err) {
console.log(err)
} else {
//lots of code here
}
})
}, 10 * 1000)
}
edit: This is the content of the JSON file.
{
"queue": [],
"waiting": [],
"lowLevel": [],
"placeHolder": [
{
"test": "test"
}
]
}
The arrays are being pushed to, and then spliced a couple times a minute.
After searching here and some forums, I've tried using fs.readFileSync, which makes the code not run at all. And now I'm finding some specific examples of this error that I can't quite seem to make the solutions apply to me. If anyone has any idea of what I should be changing, It would be appreciated.
Thanks in advance.

Answer 1

As the errors said data is not in json type
Can you make sure the file is valid and it's is what JSON.parse() can parse

Answer 2

How to use fs.readFileSync
Using fs.readFileSync returns a buffer. You can easily convert the buffer into something readable. You use buffer.toString('ascii'). Also, fs.readFile has a callback argument while readFileSync DOESN'T. What I think you were doing about readFileSync was:
fs.readFileSync('./rankedQueue.json', 'utf8', function(err, data) {
const file = JSON.parse(data); //The line the error occurs
if (err) {
console.log(err)
} else {
//lots of code here
}
})
But you should actually be doing this:
var data = fs.readFileSync('./rankedQueue.json');
var JSON = JSON.parse(data.toString('ascii'));
You could drop the 'ascii'.
Incorrect / Hacky Answer
Use require instead. Node.JS has it so it can parse a JSON file for you. Keep in mind that the way you require a file compared to fs is different.
If your code is located at /project/foobar/code.js
JSON is at /project/rankedQueue.json
fs automatically goes to the top of where your project folder is, e.g. /project & So ./rankedQueue.json
require does not do this, and stays in the folder where the file is. You have to add ../ for every folder you want to go above. So: ./../rankedQueue.json.
I'd suggest also running your JSON through a validator as well so it can tell you whats wrong.