private Task <QueryTrace> GetQueryTrace(QueryTrace trace, HashedWheelTimer timer, int attempt)
{
if (attempt >= TraceMaxAttempts)
{
return(TaskHelper.FromException <QueryTrace>(
new TraceRetrievalException(string.Format("Unable to retrieve complete query trace after {0} tries", TraceMaxAttempts))));
}
var sessionQuery = string.Format(SelectTraceSessions, trace.TraceId);
var fetchAndAdapt = Cc
.QueryAsync(sessionQuery)
.ContinueSync(rs =>
{
var sessionRow = rs.FirstOrDefault();
if (sessionRow == null || sessionRow.IsNull("duration"))
{
return(null);
}
trace.RequestType = sessionRow.GetValue <string>("request");
trace.DurationMicros = sessionRow.GetValue <int>("duration");
trace.Coordinator = sessionRow.GetValue <IPAddress>("coordinator");
trace.Parameters = sessionRow.GetValue <IDictionary <string, string> >("parameters");
trace.StartedAt = sessionRow.GetValue <DateTimeOffset>("started_at").ToFileTime();
if (sessionRow.GetColumn("client") != null)
{
//client column was not present in previous
trace.ClientAddress = sessionRow.GetValue <IPAddress>("client");
}
return(trace);
});
return(fetchAndAdapt.Then(loadedTrace =>
{
if (loadedTrace == null)
{
//Trace session was not loaded
return TaskHelper
.ScheduleExecution(() => GetQueryTrace(trace, timer, attempt + 1), timer, TraceAttemptDelay)
.Unwrap();
}
var eventsQuery = string.Format(SelectTraceEvents, trace.TraceId);
return Cc
.QueryAsync(eventsQuery)
.ContinueSync(rs =>
{
var events = rs
.Select(row => new QueryTrace.Event(
row.GetValue <string>("activity"),
row.GetValue <TimeUuid>("event_id").GetDate(),
row.GetValue <IPAddress>("source"),
row.GetValue <int?>("source_elapsed") ?? 0,
row.GetValue <string>("thread")))
.ToList();
loadedTrace.Events = events;
return loadedTrace;
});
}));
}
internal Task <QueryTrace> GetQueryTrace(QueryTrace trace, HashedWheelTimer timer)
{
return(GetQueryTrace(trace, timer, 0));
}
/// <summary>
/// Gets the trace information for the query execution without blocking.
/// </summary>
public Task <QueryTrace> GetQueryTraceAsync()
{
return(QueryTrace.LoadAsync());
}
/// <summary>
/// Gets the query trace.
/// </summary>
/// <param name="trace">The query trace that contains the id, which properties are going to be populated.</param>
/// <returns></returns>
internal Task <QueryTrace> GetQueryTraceAsync(QueryTrace trace)
{
return(_schemaParser.GetQueryTrace(trace, Configuration.Timer));
}
internal void SetQueryTrace(QueryTrace queryTrace)
{
QueryTrace = queryTrace;
}