List filenames recursively in a directory using this utility function.

#filesystem #node #opensource #recursive

In this article, we will review a function named listRecursively found in unbuild/src/utils.ts

export function listRecursively(path: string): string[] {
  const filenames = new Set<string>();
  const walk = (path: string): void => {
    const files = readdirSync(path);
    for (const file of files) {
      const fullPath = resolve(path, file);
      if (statSync(fullPath).isDirectory()) {
        filenames.add(fullPath + "/");
        walk(fullPath);
      } else {
        filenames.add(fullPath);
      }
    }
  };
  walk(path);
  return [...filenames];
}

This codesnippet does below:

Initialise filenames to a Set

const filenames = new Set<string>();

Using a Set prevents duplicate file names, if you wish to include duplicate files names, you are better off using an array.

I study large open-source projects and provide insights, give my repository a star.

Define walk function with path parameter

const walk = (path: string): void => {

Get the list of files/directorites

const files = readdirSync(path);

readdirSync is an API used to read the contents of the directory. Read more about readdirSync.

Loop through files and get full path

for (const file of files) {
      const fullPath = resolve(path, file);

Check if the path is a directory

// statSync provides an API to check if the given path is a directory.
if (statSync(fullPath).isDirectory()) {
  // Add the path to filenames set
  // filenames is a set and add is used add the fullPath
  filenames.add(fullPath + "/");
  // Call walk function recursively
  walk(fullPath);
} else {
  // filenames is a set and add is used add the fullPath
  filenames.add(fullPath);
}

Call the walk function.

 walk(path);

Return the file names

return [...filenames];

About me:

Hey, my name is Ramu Narasinga. I study large open-source projects and create content about their codebase architecture and best practices, sharing it through articles, videos.

I am open to work on interesting projects. Send me an email at ramu.narasinga@gmail.com

My Github — https://github.com/ramu-narasinga

My website — https://ramunarasinga.com

My Youtube channel — https://www.youtube.com/@thinkthroo

Learning platform — https://thinkthroo.com

Codebase Architecture — https://app.thinkthroo.com/architecture

Best practices — https://app.thinkthroo.com/best-practices

Production-grade projects — https://app.thinkthroo.com/production-grade-projects