void getUserDomain_fromSubjectPrincipal() {
            Subject subject = new Subject();
            Principal kp = new KerberosPrincipal("******@****.***");
            subject.getPrincipals().add(kp);

            Kerb5Authenticator auth = new Kerb5Authenticator(subject);
            assertEquals("EXAMPLE.COM", auth.getUserDomain());
        }

        @Test

	DiskID      string `msg:"id"`
	SrcVolume   string `msg:"sv"`
	SrcFilePath string `msg:"sp"`
	DstVolume   string `msg:"dv"`
	DstFilePath string `msg:"dp"`
	Meta        []byte `msg:"m"`
	SkipParent  string `msg:"kp"`
}

// ReadAllHandlerParams are parameters for ReadAllHandler.
type ReadAllHandlerParams struct {
	DiskID   string `msg:"id"`
	Volume   string `msg:"v"`
	FilePath string `msg:"fp"`
}