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Blob versioning

Blob versioning automatically preserves earlier blob states after versioning is enabled for the storage account. Unlike blob snapshots, versions are created by Azure when supported write operations create or modify a blob.

List And Read Blob Versions​

List versions and select one by its opaque version identifier:

use AzureOss\Storage\Blob\Models\BlobInclude;
use AzureOss\Storage\Blob\Models\GetBlobsOptions;

$versions = $container->getBlobs(
    prefix: $blob->blobName,
    options: new GetBlobsOptions(includes: [BlobInclude::VERSIONS]),
);

foreach ($versions as $item) {
    if ($item->versionId === null || $item->isLatestVersion) {
        continue;
    }

    $version = $blob->withVersion($item->versionId);
    $content = $version->downloadStreaming()->content->getContents();
}

getProperties() and download results also expose BlobProperties::$versionId and BlobProperties::$isLatestVersion.

withVersion() returns a new client and does not modify the original client. Use withVersion(null) to derive a client without the version selector.

Restore A Previous Version​

Copy a previous version over the base blob to restore it. This creates a new current version and preserves the selected previous version:

$version = $blob->withVersion($versionId);
$blob->syncCopyFromUri($version->uri);

Delete A Previous Version​

Delete one previous version without affecting the current blob:

$blob->withVersion($versionId)->delete();

Generate A Version SAS​

Calling generateSasUri() on a version client creates a version-specific SAS (sr=bv) and preserves the version selector in the URI:

use AzureOss\Storage\Blob\Sas\BlobSasBuilder;
use AzureOss\Storage\Blob\Sas\BlobSasPermissions;

$versionSas = $version->generateSasUri(
    BlobSasBuilder::new()
        ->setPermissions(new BlobSasPermissions(read: true))
        ->setExpiresOn((new DateTimeImmutable)->modify('+5 minutes')),
);