Copy folder recursively in Node.js

Question

Is there an easier way to copy a folder and all its content without manually doing a sequence of fs.readir, fs.readfile, fs.writefile

Answer 1

Since I'm just building a simple Node.js script, I didn't want the users of the script to need to import a bunch of external modules and dependencies, so I put on my thinking cap and did a search for running commands from the Bash shell.

This Node.js code snippet recursively copies a folder called node-webkit.app to a folder called build:

child = exec("cp -r node-webkit.app build", function(error, stdout, stderr) {
    sys.print("stdout: " + stdout);
    sys.print("stderr: " + stderr);
    if(error !== null) {
        console.log("exec error: " + error);
    } else {

    }
});

Thanks to Lance Pollard at dzone for getting me started.

The above snippet is limited to Unix-based platforms, like macOS and Linux, but a similar technique may work for Windows.

Answer 2

For a Linux/Unix OS, you can use the shell syntax

const shell = require('child_process').execSync;

const src = `/path/src`;
const dist = `/path/dist`;

shell(`mkdir -p ${dist}`);
shell(`cp -r ${src}/* ${dist}`);

That's it!

Answer 3

There are some modules that support copying folders with their content. The most popular would be wrench.js:

// Deep-copy an existing directory
wrench.copyDirSyncRecursive('directory_to_copy', 'location_where_copy_should_end_up');

An alternative would be node-fs-extra:

fs.copy('/tmp/mydir', '/tmp/mynewdir', function (err) {
  if (err) {
    console.error(err);
  } else {
    console.log("success!");
  }
}); // Copies directory, even if it has subdirectories or files

Answer 4

This is how I did it:

let fs = require('fs');
let path = require('path');

Then:

let filePath = // Your file path

let fileList = []
    var walkSync = function(filePath, filelist)
    {
        let files = fs.readdirSync(filePath);
        filelist = filelist || [];
        files.forEach(function(file)
        {
            if (fs.statSync(path.join(filePath, file)).isDirectory())
            {
                filelist = walkSync(path.join(filePath, file), filelist);
            }
            else
            {
                filelist.push(path.join(filePath, file));
            }
        });

        // Ignore hidden files
        filelist = filelist.filter(item => !(/(^|\/)\.[^\/\.]/g).test(item));

        return filelist;
    };

Then call the method:

This.walkSync(filePath, fileList)

Answer 5

The one with symbolic link support + doesn't throw if the destination directory already exists.

function copyFolderSync(from, to) {
  try {
    fs.mkdirSync(to);
  } catch(e) {}

  fs.readdirSync(from).forEach((element) => {
    const stat = fs.lstatSync(path.join(from, element));
    if (stat.isFile()) {
      fs.copyFileSync(path.join(from, element), path.join(to, element));
    } else if (stat.isSymbolicLink()) {
      fs.symlinkSync(fs.readlinkSync(path.join(from, element)), path.join(to, element));
    } else if (stat.isDirectory()) {
      copyFolderSync(path.join(from, element), path.join(to, element));
    }
  });
}

Answer 6

If you are on Linux, and performance is not an issue, you may use the exec function from child_process module, to execute a Bash command:

const { exec } = require('child_process');
exec('cp -r source dest', (error, stdout, stderr) => {...});

In some cases, I found this solution cleaner than downloading an entire module or even using the fs module.