ProcessEvents(IReadOnlyList <string> serializedEvents)
{
lock (process)
{
var responses =
serializedEvents.Select(serializedEvent => process.ProcessEvent(serializedEvent))
.ToImmutableList();
var compositionRecord = new CompositionRecordInFile
{
ParentHashBase16 = CommonConversion.StringBase16FromByteArray(lastStateHash),
AppendedEvents = serializedEvents.Select(@event => new ValueInFile {
LiteralString = @event
}).ToImmutableList(),
};
var serializedCompositionRecord =
Encoding.UTF8.GetBytes(Serialize(compositionRecord));
var compositionHash = CompositionRecordInFile.HashFromSerialRepresentation(serializedCompositionRecord);
lastStateHash = compositionHash;
return(responses, (serializedCompositionRecord, compositionHash));
}
}
public (byte[] serializedCompositionRecord, byte[] serializedCompositionRecordHash) SetState(string state)
{
lock (process)
{
process.SetSerializedState(state);
var compositionRecord = new CompositionRecordInFile
{
ParentHashBase16 = CommonConversion.StringBase16FromByteArray(lastStateHash),
SetState = new ValueInFile {
LiteralString = state
},
};
var serializedCompositionRecord =
Encoding.UTF8.GetBytes(Serialize(compositionRecord));
var compositionHash = CompositionRecordInFile.HashFromSerialRepresentation(serializedCompositionRecord);
lastStateHash = compositionHash;
return(serializedCompositionRecord, compositionHash);
}
}
public PersistentProcessWithHistoryOnFileFromElm019Code(
IProcessStoreReader storeReader,
IImmutableDictionary <IImmutableList <string>, IImmutableList <byte> > elmAppFiles,
Action <string> logger,
ElmAppInterfaceConfig?overrideElmAppInterfaceConfig = null)
{
(process, (JavascriptFromElmMake, JavascriptPreparedToRun)) =
ProcessFromElm019Code.ProcessFromElmCodeFiles(elmAppFiles, overrideElmAppInterfaceConfig);
var restoreStopwatch = System.Diagnostics.Stopwatch.StartNew();
logger?.Invoke("Begin to restore the process state using the storeReader.");
var emptyInitHash = CompositionRecordInFile.HashFromSerialRepresentation(new byte[0]);
string dictKeyForHash(byte[] hash) => Convert.ToBase64String(hash);
var compositionRecords = new Dictionary <string, (byte[] compositionRecordHash, CompositionRecord compositionRecord)>();
var compositionChain = new Stack <(byte[] hash, CompositionRecord composition)>();
foreach (var serializedCompositionRecord in storeReader.EnumerateSerializedCompositionsRecordsReverse())
{
{
var compositionRecordFromFile = JsonConvert.DeserializeObject <CompositionRecordInFile>(
System.Text.Encoding.UTF8.GetString(serializedCompositionRecord));
var compositionRecordHash = CompositionRecordInFile.HashFromSerialRepresentation(serializedCompositionRecord);
var compositionRecord =
new CompositionRecord
{
ParentHash =
CommonConversion.ByteArrayFromStringBase16(compositionRecordFromFile.ParentHashBase16),
SetStateLiteralString = compositionRecordFromFile.SetState?.LiteralString,
AppendedEventsLiteralString =
compositionRecordFromFile.AppendedEvents?.Select(@event => @event.LiteralString)?.ToImmutableList(),
};
var compositionChainElement = (compositionRecordHash, compositionRecord);
if (!compositionChain.Any())
{
compositionChain.Push(compositionChainElement);
}
else
{
compositionRecords[dictKeyForHash(compositionRecordHash)] = compositionChainElement;
}
}
while (true)
{
var(compositionRecordHash, compositionRecord) = compositionChain.Peek();
var reduction = storeReader.GetReduction(compositionRecordHash);
if (reduction != null || emptyInitHash.SequenceEqual(compositionRecord.ParentHash))
{
if (reduction != null)
{
compositionChain.Pop();
process.SetSerializedState(reduction.ReducedValueLiteralString);
lastStateHash = reduction.ReducedCompositionHash;
}
foreach (var followingComposition in compositionChain)
{
if (followingComposition.composition.SetStateLiteralString != null)
{
process.SetSerializedState(followingComposition.composition.SetStateLiteralString);
}
foreach (var appendedEvent in followingComposition.composition.AppendedEventsLiteralString.EmptyIfNull())
{
process.ProcessEvent(appendedEvent);
}
lastStateHash = followingComposition.hash;
}
logger?.Invoke("Restored the process state in " + ((int)restoreStopwatch.Elapsed.TotalSeconds) + " seconds.");
return;
}
var parentKey = dictKeyForHash(compositionRecord.ParentHash);
if (!compositionRecords.TryGetValue(parentKey, out var compositionChainElementFromPool))
{
break;
}
compositionChain.Push(compositionChainElementFromPool);
compositionRecords.Remove(parentKey);
}
}
if (compositionChain.Any())
{
throw new NotImplementedException(
"I did not find a reduction for any composition on the chain to the last composition (" +
CommonConversion.StringBase16FromByteArray(compositionChain.Last().hash) +
").");
}
logger?.Invoke("Found no composition record, default to initial state.");
lastStateHash = emptyInitHash;
}
static string Serialize(CompositionRecordInFile composition) => JsonConvert.SerializeObject(composition, recordSerializationSettings);
