NewBlobClientFactory returns a BlobClientFactory.

NewBlobService instantiates a blob service server.

NewLocalStorage creates a new LocalStorage object and returns an error when we cannot take the absolute path of `externalIODir`.

TestBlobServiceClient can be used as a mock BlobClient in tests that use nodelocal storage.

TestEmptyBlobClientFactory can be used as a mock BlobClient in tests that create ExternalStorage but do not use nodelocal storage.

LocalStorage wraps all operations with the local file system that the blob service makes.

Service implements the gRPC BlobService which exchanges bulk files between different nodes.

BlobClient provides an interface for file access on all nodes' local storage.

BlobClientFactory creates a blob client based on the nodeID we are dialing.