private async Task ReplayEvents(ILoggerFactory loggerFactory, DenormalizerDispatcher dispatcher,
AzureTableStorageOptions dboptions)
{
var logger = loggerFactory.CreateLogger("Replay");
logger.LogInformation("Replaying all the events from event store to denormalizers.");
var tc = new TelemetryClient();
var watch = Stopwatch.StartNew();
var eventStore = new EventStream(dboptions);
var allEvents = await eventStore.ReadAllEvents();
watch.Stop();
tc.TrackMetric("LoadEvents", watch.ElapsedMilliseconds);
Trace.TraceInformation("Events queried from event store in {0:n0} ms.", watch.ElapsedMilliseconds);
watch = Stopwatch.StartNew();
var i = 0;
foreach (var e in allEvents)
{
dispatcher.ReplayEvent(e);
i++;
}
watch.Stop();
logger.LogInformation("Replay complete in {0:n0} ms. Replayed {1} events.", watch.ElapsedMilliseconds, i);
tc.TrackMetric("ReplayEvents", watch.ElapsedMilliseconds);
tc.TrackMetric("ReplayEventsCount", i);
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
// Since this method is resolved through the DI already, we can request any registered services by
// just adding respective parameters.
public void Configure(
IApplicationBuilder app,
IHostingEnvironment env,
ILoggerFactory loggerFactory,
IEventTopic eventTopic,
DenormalizerDispatcher dispatcher,
CommandHandlerFactory commandHandlerFactory,
IOptions <AzureTableStorageOptions> tableStorageOptions,
IHubContext <CommandBus> commandBus)
{
Startup.CommandBus = commandBus;
var configureLogger = loggerFactory.CreateLogger("Configure");
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
app.UseRewriter(new RewriteOptions().AddRedirectToHttps());
}
app.UseStaticFiles();
app.UseAuthentication();
// Replay all events once from DB to the in-memory query model.
// Explicitly wait as routing (below) and controllers expect the state is loaded .
ReplayEvents(loggerFactory, dispatcher, tableStorageOptions.Value).Wait();
// Register all denormalizers to listen for all events. Could have more fine grained subscription logic, but this works for now.
foreach (var d in dispatcher.Denormalizers.Cast <IEventConsumer>())
{
configureLogger.LogInformation("Registering denormalizer {0} to receive all events", d.GetType());
eventTopic.Subscribe(d);
}
// Register all command handlers to listen for all events.
foreach (var d in commandHandlerFactory.All.Cast <IEventConsumer>())
{
configureLogger.LogInformation("Registering command handler {0} to receive all events", d.GetType());
eventTopic.Subscribe(d);
}
// Routes use event data (state after events), therefore register routes only after the replay
string defaultHappening = QueryModelRepository.Routing.DefaultHappening;
app.UseMvc(routes =>
{
routes.MapRoute(
name: "root",
template: "{happening:regex(^satku[a-z]+$)?}",
defaults: new { happening = defaultHappening, Controller = "Home", Action = "Index" },
constraints: null,
dataTokens: new { DefaultHappening = defaultHappening });
routes.MapRoute(
name: "default",
template: "{happening:regex(^satku[a-z]+$)}/{*catchall}",
defaults: new { happening = defaultHappening, Controller = "Home", Action = "Index" },
constraints: null,
dataTokens: new { DefaultHappening = defaultHappening });
});
app.UseSignalR(routes =>
{
routes.MapHub <CommandBus>("commandbus");
});
}
