FirebaseStorage: How to Delete Directory

FirebaseStorage always returns error 400 when I try to delete a directory i.e. something like the following always returns error 400.

let storageRef = FIRStorage.storage().reference().child("path/to/directory")
storageRef.deleteWithCompletion { (error) in
    print("error: \(error)") // always prints error code 400
}

However, deleting a file works fine e.g. something like doesn't return an error:

let storageRef = FIRStorage.storage().reference().child("path/to/file.jpg")
storageRef.deleteWithCompletion { (error) in
    print("error: \(error)") // works fine, error is nil
}

What could I be doing wrong here? I don't reckon it's not supported by FirebaseStorage because deleting files from a directory one by one would be pretty lame (specially if the said directory has 100s or 1000s of these).

Solution 1:

From the context of a secure google cloud function - you can delete an entire directory using the Google Cloud Storage npm package (aka Google Cloud Storage API) like so:

const gcs = require('@google-cloud/storage')();
const functions = require('firebase-functions');
...
  const bucket = gcs.bucket(functions.config().firebase.storageBucket);

  return bucket.deleteFiles({
    prefix: `users/${userId}/`
  }, function(err) {
    if (err) {
      console.log(err);
    } else {
      console.log(`All the Firebase Storage files in users/${userId}/ have been deleted`);
    }
  });

more documentation available on GCS API docs

Solution 2:

In 2020, deleting Firebase Storage folder seems to just work. I just did, in my Cloud Functions (Node.js Admin), below and it deletes folder, sub-folders, and files in them. I did download Google Cloud Storage using npm, but I didn't import that library in anyway physically, and it seems Firebase Storage is now supporting this feature unlike what everyone said above. Maybe they have updated it. I tested it that it is working.

admin.initializeApp({
    storageBucket: "bucket_name.appspot.com",
})

const bucket = admin.storage().bucket();
await bucket.deleteFiles({
   prefix: `${folderName}/`
});