public async Task <IApiResponse> PostAsync(Span[][] traces, FormatterResolverWrapper formatterResolver)
{
// re-create HttpContent on every retry because some versions of HttpClient always dispose of it, so we can't reuse.
using (var content = new TracesMessagePackContent(traces, formatterResolver))
{
_request.Content = content;
var response = await _client.SendAsync(_request).ConfigureAwait(false);
return(new HttpClientResponse(response));
}
}
public async Task SendTracesAsync(Span[][] traces)
{
// retry up to 5 times with exponential back-off
var retryLimit = 5;
var retryCount = 1;
var sleepDuration = 100; // in milliseconds
var traceIds = GetUniqueTraceIds(traces);
while (true)
{
HttpResponseMessage responseMessage;
try
{
// re-create HttpContent on every retry because some versions of HttpClient always dispose of it, so we can't reuse.
using (var content = new TracesMessagePackContent(traces, _formatterResolver))
{
content.Headers.Add(AgentHttpHeaderNames.TraceCount, traceIds.Count.ToString());
try
{
_statsd?.AppendIncrementCount(TracerMetricNames.Api.Requests);
responseMessage = await _client.PostAsync(_tracesEndpoint, content).ConfigureAwait(false);
}
catch
{
// count the exceptions thrown by the HttpClient,
// not responses with 5xx status codes
// (which cause EnsureSuccessStatusCode() to throw below)
_statsd?.AppendIncrementCount(TracerMetricNames.Api.Errors);
throw;
}
if (_statsd != null)
{
// don't bother creating the tags array if trace metrics are disabled
string[] tags = { $"status:{(int)responseMessage.StatusCode}" };
// count every response, grouped by status code
_statsd.AppendIncrementCount(TracerMetricNames.Api.Responses, tags: tags);
}
responseMessage.EnsureSuccessStatusCode();
}
}
catch (Exception ex)
{
#if DEBUG
if (ex.InnerException is InvalidOperationException ioe)
{
Log.Error("An error occurred while sending traces to the agent at {Endpoint}\n{Exception}", ex, _tracesEndpoint, ex.ToString());
return;
}
#endif
if (retryCount >= retryLimit)
{
// stop retrying
Log.Error("An error occurred while sending traces to the agent at {Endpoint}", ex, _tracesEndpoint);
return;
}
// retry
await Task.Delay(sleepDuration).ConfigureAwait(false);
retryCount++;
sleepDuration *= 2;
TracingProcessManager.TraceAgentMetadata.ForcePortFileRead();
continue;
}
try
{
if (responseMessage.Content != null && Tracer.Instance.Sampler != null)
{
// build the sample rate map from the response json
var responseContent = await responseMessage.Content.ReadAsStringAsync().ConfigureAwait(false);
var response = JsonConvert.DeserializeObject<ApiResponse>(responseContent);
Tracer.Instance.Sampler.SetDefaultSampleRates(response?.RateByService);
}
}
catch (Exception ex)
{
Log.Error("Traces sent successfully to the Agent at {Endpoint}, but an error occurred deserializing the response.", ex, _tracesEndpoint);
}
_statsd?.Send();
return;
}
}
