Create an empty folder in AWS S3 with aws sdk (nodejs)

Question

I'm trying to create a folder in aws s3 I succeded in making a folder but not empty.

const Obj = new AWS.S3().putObject({
 
  Key: `/`, //the file you should put inside the folder
  Bucket: `${bucketName}/${req.body.modpack}`, // main bucket/folder I want to create
});

I'm not able to remove the "key" if I do that I recive and erro that force me to add it

Answer 1

In Amazon S3, buckets and objects are the primary resources, and objects are stored in buckets. Amazon S3 has a flat structure instead of a hierarchy like you would see in a file system. However, for the sake of organizational simplicity, the Amazon S3 console supports the folder concept as a means of grouping objects. Amazon S3 does this by using a shared name prefix for objects (that is, objects have names that begin with a common string). Object names are also referred to as key names.

Also. S3 is not your typical file system. It's an object-store. It has buckets and objects. Buckets are used to store objects, and objects comprise data (basically a file) and metadata (information about the file). When compared to a traditional file system, it's more natural to think of an S3 bucket as a drive rather than as a folder.

So in order to create an object or as we term it a folder, you would need to provide a folder name with a trailing "/" like this:

const Obj = new AWS.S3().putObject({
 
  Key: `EmptyFolder/`, // This should create an empty object in which we can store files 
  Bucket: `${bucketName}`,
});

Ref: https://docs.aws.amazon.com/AmazonS3/latest/user-guide/using-folders.html

Answer 2

Folders do not exist in Amazon S3.

However, the Amazon S3 management console allows you to 'create' a folder. It does this by creating a zero-length object with a Key (filename) equal to the 'folder' name. This causes the folder to appear when using the console, or when retrieve CommonPrefixes via the S3 API.

In general, you should not have a need to create folders. Simply copy files to their desired destination and it will magically work, eg:

aws s3 cp foo.txt s3://my-bucket/invoices/january/foo.txt

This will cause the invoices and january folders to 'appear'. If all objects in that directory are deleted, then the folders will 'disappear' (because they never existed).