async Task Run(IEnv env)
{
_expectedCount = 0M;
var endpoints = Servers.Select(m => new SimEndpoint(m, Port)).ToArray();
var lib = new BackendClient(env, endpoints);
await lib.AddItem(0, 1);
_expectedCount = 1M;
for (int i = 0; i < Iterations; i++)
{
try {
var curr = i % RingSize;
var next = (i + 1) % RingSize;
await lib.MoveItem(curr, next, 1);
await env.Delay(Delay);
} catch (ArgumentException ex) {
env.Error("Unexpected error", ex);
}
}
_actualCount = await lib.Count();
if (HaltOnCompletion)
{
env.Halt("DONE");
}
}
async Task ProjectionThread()
{
// TODO: deduplication
while (!_env.Token.IsCancellationRequested)
{
try {
var position = _store.GetCounter();
var events = await _client.Read(position, int.MaxValue);
if (events.Count > 0)
{
//_env.Debug($"Projecting {events.Count} events");
foreach (var e in events)
{
_proj.Dispatch(e);
}
position += events.Count;
_store.SetCounter(position);
}
await _env.Delay(100.Ms());
} catch (TaskCanceledException) {
// nothing
return;
} catch (Exception ex) {
_env.Warning($"Projection error: {ex.Message}");
}
}
}
public static async Task SendWithBackOff(IEnv env, int recipient, object msg)
{
var counter = 0;
while (true)
{
try {
await env.Send(recipient, msg);
return;
} catch (Exception ex) {
if (counter < 10)
{
counter++;
var sleep = TimeSpan.FromSeconds(Math.Pow(2, counter));
env.Debug($"Retrying send on {ex.Message} #{counter} after {sleep.TotalSeconds} seconds");
await env.Delay(sleep);
continue;
}
throw;
}
}
}
async Task <TResponse> Unary <TRequest, TResponse>(TRequest req)
{
var now = _env.Time;
foreach (var(i, ts, mark) in GetEndpoints())
{
var endpoint = _endpoints[i];
_env.Debug($"Send '{req}' to {endpoint}");
if (ts != TimeSpan.Zero)
{
await _env.Delay(ts, _env.Token);
}
try {
using (var conn = await _env.Connect(endpoint)) {
await conn.Write(req);
var res = await conn.Read(5.Sec());
if (res is ArgumentException ex)
{
throw new ArgumentException(ex.Message);
}
return((TResponse)res);
}
} catch (IOException ex) {
if (!mark)
{
_env.Warning($"! {ex.Message} for '{req}'. Retrying {endpoint}");
continue;
}
if (_outages[i] > now)
{
_env.Warning($"! {ex.Message} for '{req}'. {endpoint} already DOWN");
}
else
{
_env.Warning($"! {ex.Message} for '{req}'. {endpoint} DOWN");
_outages[i] = now + _downtime;
}
}
}
// we've exhausted all gateways.
throw new IOException("No gateways active");
}
async Task ScheduleStore()
{
var next = TimeSpan.FromSeconds(Math.Ceiling(_env.Time.TotalSeconds * 2) / 2);
if (_scheduled != next)
{
_scheduled = next;
await _env.Delay(_scheduled - _env.Time);
if (_buffer.Count > 0)
{
await _env.SimulateWork((5 * _buffer.Count + 10).Ms());
_stored.AddRange(_buffer);
_env.Debug($"Store {_buffer.Count} events");
_buffer.Clear();
}
}
}