How to create a folder within S3 bucket using PHP

Question

I'm trying to create a folder within an S3 amazon bucket but I'm finding it difficult to find the right documentation to adequately explain what is needed. I have the following code / pseudocode for creating a folder. Can anyone explain or provide a sample of the arguments I need to place within the code

use vendor\aws\S3\S3Client;

$bucket_url = 'https://***.amazonaws.com/***/';
$folder_name = $username . '/';

$s3Client = new vendor\aws\S3\S3Client([
        'version' => AWS_VERSION,
        'region' => AWS_REGION,
        'credentials' => [
            'key' => AWS_KEY,
            'secret' =>AWS_SECRET,
        ],
    ]);

    $s3Client->putObject(array(
        'Bucket' => AWS_BUCKET, // Defines name of Bucket
        'Key' => AWS_PATH . $folder_name, //Defines Folder name
        'Body' => "",
    ));

Answer 1

S3 doesn't have folders beyond the bucket, but objects (files) can have /s (forward slashes) in their name, and there are methods to retrieve based on a prefix that allows you to emulate a directory-list. This means though, that you can't create an empty folder.

So a work around will be put a empty txt file and delete it after wards but the folder structure will stay.

/* function to upload empty test.txt file to subfolders /folder/ on S3 bucketname */
$s3->putObjectFile(‘test.txt’, ‘bucketname’, ‘/folder/test.txt’, S3::ACL_PUBLIC_READ);

/* function to delete empty test.txt file to subfolders /folder/ on S3 bucketname */
$s3->deleteObject(‘bucketname’, ‘/folder/test.txt’);

Answer 2

Amazon S3 does not have a concept of folders. For S3, all objects are simply a key name with data.

Folders are a human concept which use the '/' character to separate the folders. But S3 does not care.

When you use many third-party tools (and even the AWS Management Console), the tools often will look at the object keys under your prefix and when it sees a '/' in it, it will interpret it as a folder.

But there's no way to "create a folder".

If you you simply PutObject an object with a key with your desired full path (for example, "my/desired/folder/structure/file.txt"), Amazon S3 will put it there. It's not like many filesystems where the folder must exist before a file can be created.

The closest thing to "creating a folder" you could do is to create a 0-byte object with a '/' at the end of it's key. For example "my/desired/folder/structure/". But it will just be another object in the bucket. It won't have any effect on the creation or operation of the bucket or any other objects in the bucket.