public async Task <TSideEffect> Process <TState, TSideEffect>(string requestId, string stateId,
Func <TState, TSideEffect> handle, CancellationToken cancellationToken = default) where TState : State, new()
{
var(state, version) = await stateStore.Load <TState>(stateId, cancellationToken)
.ConfigureAwait(false);
if (state.TxId != null)
{
await FinishTransaction(stateId, state, version, cancellationToken)
.ConfigureAwait(false);
}
var outboxState = await outboxStore.Get(requestId, cancellationToken);
if (outboxState != null)
{
return(JsonConvert.DeserializeObject <TSideEffect>(outboxState.SideEffect));
}
var sideEffect = handle(state);
state.TxId = Guid.NewGuid();
outboxState = new OutboxItem
{
Id = state.TxId.ToString(),
RequestId = requestId,
SideEffect = JsonConvert.SerializeObject(sideEffect)
};
await outboxStore.Store(outboxState, cancellationToken)
.ConfigureAwait(false);
string nextVersion;
try
{
nextVersion = await stateStore.Upsert(stateId, state, version, cancellationToken)
.ConfigureAwait(false);
}
catch (Exception e) when(!(e is OperationCanceledException))
{
await outboxStore.Delete(outboxState.Id, cancellationToken)
.ConfigureAwait(false);
throw;
}
await FinishTransaction(stateId, state, nextVersion, cancellationToken)
.ConfigureAwait(false);
return(sideEffect);
}
public async Task <TSideEffect> Process <TState, TSideEffect>(string requestId, string stateId,
Func <TState, TSideEffect> handle) where TState : State, new()
{
var(state, version) = await stateStore.Load <TState>(stateId);
if (state.TxId != null)
{
await FinishTransaction(stateId, state, version);
}
var outboxState = await outboxStore.Get(requestId);
if (outboxState == null)
{
var sideEffect = handle(state);
state.TxId = Guid.NewGuid();
outboxState = new OutboxItem
{
Id = state.TxId.ToString(),
RequestId = requestId,
SideEffect = JsonConvert.SerializeObject(sideEffect)
};
await outboxStore.Store(outboxState);
string nextVersion;
try
{
nextVersion = await stateStore.Upsert(stateId, state, version);
}
catch
{
await outboxStore.Delete(outboxState.Id);
throw;
}
await FinishTransaction(stateId, state, nextVersion);
return(sideEffect);
}
return(JsonConvert.DeserializeObject <TSideEffect>(outboxState.SideEffect));
}
public async Task Store(OutboxItem outboxItem)
{
var json = JsonConvert.SerializeObject(outboxItem, settings);
await using var stream = new MemoryStream();
await using var writer = new StreamWriter(stream);
writer.Write(json);
writer.Flush();
stream.Position = 0;
var response = await container.UpsertItemStreamAsync(stream, PartitionKey.None);
// HINT: Outbox item should be created or re-updated (if there was a failure
// during previous commit).
if (response.StatusCode != HttpStatusCode.Created &&
response.StatusCode != HttpStatusCode.OK)
{
throw new Exception("Error storing outbox item");
}
}
public async Task Store(OutboxItem outboxItem, CancellationToken cancellationToken = default)
{
// ReSharper disable once UseAwaitUsing
using var stream = MemoryStreamManager.GetStream();
// ReSharper disable once UseAwaitUsing
using var streamWriter = new StreamWriter(stream);
using var writer = new JsonTextWriter(streamWriter);
serializer.Serialize(writer, outboxItem);
await streamWriter.FlushAsync().ConfigureAwait(false);
stream.Position = 0;
var response = await container.UpsertItemStreamAsync(stream, PartitionKey.None, cancellationToken : cancellationToken);
// HINT: Outbox item should be created or re-updated (if there was a failure
// during previous commit).
if (response.StatusCode != HttpStatusCode.Created &&
response.StatusCode != HttpStatusCode.OK)
{
throw new Exception("Error storing outbox item");
}
}