private TraceInfo ReadTraceInfo(HttpContext context)
{
string headerTraceId = context.Request.Headers[TraceInfo.TraceIdHeaderName];
string headerSpanId = context.Request.Headers[TraceInfo.SpanIdHeaderName];
string headerParentSpanId = context.Request.Headers[TraceInfo.ParentSpanIdHeaderName];
string headerSampled = context.Request.Headers[TraceInfo.SampledHeaderName];
var requestPath = context.Request.Path.ToString();
var traceId = headerTraceId.IsParsableTo128Or64Bit() ? headerTraceId : TraceIdHelper.GenerateNewTraceId(_zipkinConfig.Create128BitTraceId);
var spanId = headerSpanId.IsParsableToLong() ? headerSpanId : TraceIdHelper.GenerateHexEncodedInt64Id();
var parentSpanId = headerParentSpanId.IsParsableToLong() ? headerParentSpanId : string.Empty;
var isSampled = _zipkinConfig.ShouldBeSampled(headerSampled, requestPath);
var domain = _zipkinConfig.Domain(context.Request);
var isJoinedSpan = spanId.Equals(headerSpanId);
var traceInfo = new TraceInfo(traceId, spanId, isSampled, isJoinedSpan, domain, context.Connection.LocalIpAddress, parentSpanId);
context.Items[TraceInfo.TraceInfoKey] = traceInfo;
_traceInfoAccessor.TraceInfo = traceInfo;
return(traceInfo);
}
