use node js to check if a json file exists

JavaScript
const fs = require("fs"); // Or `import fs from "fs";` with ESM
if (fs.existsSync(path)) {
    // Do something
}const fs = require('fs')

const path = './file.txt'

try {
  if (fs.existsSync(path)) {
    //file exists
  }
} catch(err) {
  console.error(err)
}
const fs = require('fs')

const path = './file.txt'
//Async method
fs.access(path, fs.F_OK, (err) => {
  if (err) {
    console.error(err)
    return
  }

  //file exists
})
function executeIfFileExist(src, callback) {
    var xhr = new XMLHttpRequest()
    xhr.onreadystatechange = function() {
        if (this.readyState === this.DONE) {
            callback()
        }
    }
    xhr.open('HEAD', src)
}
Source

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