LogStateWithMetaData<TEntry>

class

Namespace: Orleans.EventSourcing.LogStorage

A class that extends grain state with versioning metadata, so that a log-consistent grain can use a standard storage provider.

[Orleans.GenerateSerializer]
public sealed class LogStateWithMetaData<TEntry>
    where TEntry : class

Constructors

LogStateWithMetaData<TEntry> Initializes a new instance of the Orleans.EventSourcing.LogStorage.LogStateWithMetaData class.

GlobalVersion The length of the log
Log The stored view of the log
WriteVector Metadata that is used to avoid duplicate appends. Logically, this is a (string->bit) map, the keys being replica ids But this map is represented compactly as a simple string to reduce serialization/deserialization overhead Bits are read by Orleans.EventSourcing.LogStorage.LogStateWithMetaData.GetBit and flipped by Orleans.EventSourcing.LogStorage.LogStateWithMetaData.FlipBit. Bits are toggled when writing, so that the retry logic can avoid appending an entry twice when retrying a failed append.

FlipBit(string) Toggle one of the bits in Orleans.EventSourcing.LogStorage.LogStateWithMetaData.WriteVector and return the new value.
GetBit(string) Gets one of the bits in Orleans.EventSourcing.LogStorage.LogStateWithMetaData.WriteVector