S3 Gateway API

This section outlines the operations exposed by HPE Machine Learning Data Management’s HTTP API S3 Gateway.

Info

Since 1.13.3, all operations mentioning <branch>.<repo> also accept the syntax <commit>.<repo> and <commit>.<branch>.<repo>.

ListBuckets #

Route: GET /.

Lists all of the branches across all of the repos as S3 buckets.

DeleteBucket #

Route: DELETE /<branch>.<repo>/.

Deletes the branch. If it is the last branch in the repo, the repo is also deleted. Unlike S3, you can delete non-empty branches.

ListObjects #

Route: GET /<branch>.<repo>/

Only S3’s list objects v1 is supported.

PFS directories are represented via CommonPrefixes. This largely mirrors how S3 is used in practice, but leads to a couple of differences:

• If you set the delimiter parameter, it must be /.
• Empty directories are included in listed results.

With regard to listed results:

• Due to PFS peculiarities, the LastModified field references when the most recent commit to the branch happened, which may or may not have modified the specific object listed.
• The HTTP ETag field does not use MD5, but is a cryptographically secure hash of the file contents.
• The S3 StorageClass and Owner fields always have the same filler value.

GetBucketLocation #

Route: GET /<branch>.<repo>/?location

This will always serve the same location for every bucket, but the endpoint is implemented to provide better compatibility with S3 clients.

GetBucketVersioning #

Route: GET /<branch>.<repo>/?versioning

This will get whether versioning is enabled, which is always true.

ListMultipartUploads #

Route: GET /<branch>.<repo>/?uploads

Lists the in-progress multipart uploads in the given branch. The delimiter query parameter is not supported.

CreateBucket #

Route: PUT /<branch>.<repo>/.

If the repo does not exist, it is created. If the branch does not exist, it is likewise created. As per S3’s behavior in some regions (but not all), trying to create the same bucket twice will return a BucketAlreadyOwnedByYou error.

DeleteObjects #

Route: POST /<branch>.<repo>/?delete.

Deletes multiple files specified in the request payload.

DeleteObject #

Route: DELETE /<branch>.<repo>/<filepath>.

Deletes the PFS file filepath in an atomic commit on the HEAD of branch.

GetObject #

Route: GET /<branch>.<repo>/<filepath>.

By default, this request gets the HEAD version of the file. You can use s3’s versioning API to get the object at a non-HEAD commit by specifying either a specific commit ID, or by using the caret syntax – for example, HEAD^.

There is support for range queries and conditional requests, however error response bodies for bad requests using these headers are not standard S3 XML.

With regard to HTTP response headers:

• Due to PFS peculiarities, the HTTP Last-Modified header references when the most recent commit to the branch happened, which may or may not have modified this specific object.
• The HTTP ETag does not use MD5, but is a cryptographically secure hash of the file contents.

PutObject #

Route: PUT /<branch>.<repo>/<filepath>.

Writes the PFS file at filepath in an atomic commit on the HEAD of branch.

Any existing file content is overwritten. Unlike S3, there is no limit to upload size.

Unlike s3, a 64mb max size is not enforced on this endpoint. Especially, as the file upload size gets larger, we recommend setting the Content-MD5 request header to ensure data integrity.

AbortMultipartUpload #

Route: DELETE /<branch>.<repo>?uploadId=<uploadId>

Aborts an in-progress multipart upload.

CompleteMultipartUpload #

Route: POST /<branch>.<repo>?uploadId=<uploadId>

Completes a multipart upload. If ETags are included in the request payload, they must be of the same format as returned by the S3 gateway when the multipart chunks are included. If they are md5 hashes or any other hash algorithm, they are ignored.

CreateMultipartUpload #

Route: POST /<branch>.<repo>?uploads

Initiates a multipart upload.

ListParts #

Route: GET /<branch>.<repo>?uploadId=<uploadId>

Lists the parts of an in-progress multipart upload.

UploadPart #

Route: PUT /<branch>.<repo>?uploadId=<uploadId>&partNumber=<partNumber>

Uploads a chunk of a multipart upload.