completenesschecking

func NewCompletenessCheckingBlobAccess ¶

func NewCompletenessCheckingBlobAccess(actionCache blobstore.BlobAccess, contentAddressableStorage blobstore.BlobAccess, batchSize int, maximumMessageSizeBytes int) blobstore.BlobAccess

NewCompletenessCheckingBlobAccess creates a wrapper around an Action Cache (AC) that ensures that ActionResult entries are only returned in case all objects referenced by the ActionResult are present within the Content Addressable Storage (CAS). In case one of the referenced objects is absent, the ActionResult entry is treated as if non-existent.

The use of this type is required when the underlying Action Cache and Content Addressable Storage are two separate data stores that don't share a common garbage collection scheme. Tools such as Bazel rely on a single call to GetActionResult() to determine whether an action needs to be rebuilt. By calling it, Bazel indicates that all associated output files must remain present during the build for forward progress to be made.