NewURLSignerHMAC creates a URLSignerHMAC.

OpenBucket creates a *blob.Bucket backed by the filesystem and rooted at dir, which must exist.

Writes won't carry metadata, as per the package docstring.

Metadata gets written to a separate file.

Scheme is the URL scheme fileblob registers its URLOpener under on blob.DefaultMux.

Options sets options for constructing a *blob.Bucket backed by fileblob.

URLOpener opens file bucket URLs like "file:///foo/bar/baz".

URLSignerHMAC signs URLs by adding the object key, expiration time, and a hash-based message authentication code (HMAC) into the query parameters.

URLSigner defines an interface for creating and verifying a signed URL for objects in a fileblob bucket.