private static CacheDeterminism ReadDeterminism(byte[] determinismBytes, byte[] oldDeterminismBytes)
{
var determinism = CacheDeterminism.Deserialize(determinismBytes);
var oldDeterminismGuid = new Guid(oldDeterminismBytes);
// If the old guid was ToolDeterministic, we need to keep it that way.
if (oldDeterminismGuid == CacheDeterminism.Tool.Guid)
{
return(CacheDeterminism.Tool);
}
// If the old guid was SinglePhaseNonDeterministic, we need to keep it that way.
if (oldDeterminismGuid == CacheDeterminism.SinglePhaseNonDeterministic.Guid)
{
return(CacheDeterminism.SinglePhaseNonDeterministic);
}
// The newer code always sets the old "Determinism" column to the same determinism guid when it writes a new value,
// so if we read here that the determinism from the old column is different from
// the new "SerializedDeterminism" column's guid then the ContentHashList in this row was inserted by the
// old code and the new column's Determinism value is no longer valid. In that case, we return None.
return(oldDeterminismGuid == determinism.EffectiveGuid
? determinism
: CacheDeterminism.None);
}
/// <inheritdoc />
public ContentHashListWithDeterminism AsContentHashList(RedisValue value)
{
const int partCount = 5;
var parts = value.ToString().Split(new[] { RedisValueSeparator }, partCount, StringSplitOptions.None);
Contract.Assert(parts.Length == partCount);
var determinism = CacheDeterminism.Deserialize(HexUtilities.HexToBytes(parts[0]));
var payload = parts[3] == RedisValueExistsSemaphore?HexUtilities.HexToBytes(parts[4]) : null;
var hashList = parts[1] == RedisValueExistsSemaphore?ContentHashList.Deserialize(parts[2], payload) : null;
return(new ContentHashListWithDeterminism(hashList, determinism));
}