protected override async Task ProcessMessage(Message <string, string> message)
{
var @event = GrainStateModifyingEvent.Deserialize(message.Value);
if (GrainProviders.TryGetValue(@event.GrainType, out var provider))
{
var grain = (IStateProjectorGrain)provider(GrainFactory, @event.GrainKey);
await _waitPolicy.ExecuteAsync(
async (cancellationToken, context) =>
{
var currentVersion = await grain.GetCurrentVersionAsync();
return(currentVersion == @event.GrainVersion);
},
new Dictionary <string, object>
{
{ EventTypeContextKey, nameof(GrainStateModifyingEvent) },
{ GrainTypeContextKey, @event.GrainType },
{ GrainKeyContextKey, @event.GrainKey },
{ GrainVersionContextKey, @event.GrainVersion },
},
CancellationToken.None,
true);
await grain.ProjectStateAsync();
}
else
{
throw new ApplicationException(
$"Unknown grain type {@event.GrainType} used in {nameof(GrainStateModifyingEvent)}. " +
$"Please check {nameof(DataProjectionDispatchingGrain)} configuration.");
}
}
public async Task Invoke(IIncomingGrainCallContext context)
{
var attribute = context.ImplementationMethod.GetCustomAttribute <StateModificationAttribute>();
if (attribute != null)
{
if (context.Grain is IStateProjectorGrain stateProjectorGrain)
{
var grainType = context.ImplementationMethod.DeclaringType.FullName;
var grainKey = context.Grain.GetPrimaryKeyLong();
var grainVersion = await stateProjectorGrain.GetCurrentVersionAsync();
var @event = new GrainStateModifyingEvent(grainType, grainKey, grainVersion);
var message = @event.Serialize();
var messageKey = $"{grainType}|{grainKey}";
await _messageSender.SendAsync(_kafkaOptions.DataProjectionDispatchingTopic, messageKey, message);
}
}
await context.Invoke();
}
