public void Configure(IApplicationBuilder app,
IEventStoreBus eventBus,
IEventStoreProjections projections,
WebSocketHandler wsHandler,
VotingReadModelService readModelService,
ILogger <Startup> logger)
{
app.UseCors("CorsPolicy");
app.UseMvc();
app.UseSwagger();
app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "Voting API"));
app.UseWebSockets();
app.MapWebSocketManager("/ws", wsHandler);
projections.CreateAsync(Projections.Voting)
.DefaultRetryAsync()
.Wait();
eventBus.Subscribe(
async(@event) =>
{
var snapshot = await readModelService.AddOrUpdate(@event);
logger.LogInformation(snapshot.ToString());
await wsHandler.SendMessageToAllAsync(snapshot);
})
.DefaultRetryAsync()
.Wait();
}
public void Start()
{
var serviceProvider = _factory.CreateBuilder();
foreach (var subscription in _registry)
{
foreach (var handlerType in subscription.Value)
{
_logger.LogDebug($"Subscribing {handlerType} to messsage {subscription.Key}");
Retry(() => Subscribe(subscription.Key, handlerType));
}
}
void Subscribe(Type messageType, Type messageHandlerType)
{
_bus.Subscribe(messageType, _subscription,
async(object msg) =>
{
_logger.LogDebug($"Handling event type {messageType}");
dynamic handler = (IMessageHandler)serviceProvider.GetService(messageHandlerType);
await handler.Handle((dynamic)msg);
});
}
void Retry(Action action, int retries = 5) =>
Policy.Handle <Exception>()
.WaitAndRetry(retries, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)))
.Execute(action);
}