nodejs create file if not exists code example

Example 1: node check if file exists

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

Example 2: nodejs fs create file if not exists

fs.exists(filename, function(exists) {
  if(exists) {
    // Create a file
  }
  else {
    console.log("Deny overwrite existing", filename);
  }
});

Example 3: node check if file exists

const fs = require('fs');

let file = '../path/to/chad_warden.mpeg';

// async
const fileExists = (file) => {
    return new Promise((resolve) => {
        fs.access(file, fs.constants.F_OK, (err) => {
            err ? resolve(false) : resolve(true)
        });
    })
}

// sync
const fileExistsSync = (file) => {
    try {
        fs.accessSync(file, fs.constants.R_OK | fs.constants.W_OK);
        return true;
      } catch (err) {
        return false;
      }
}

Example 4: postgres create extension if not exists

CREATE EXTENSION [ IF NOT EXISTS ] extension_name
    [ WITH ] [ SCHEMA schema_name ]
             [ VERSION version ]
             [ FROM old_version ]