allow to set trace verbosity and ttl

Author: adameat

ydb/core/viewer/json_pipe_req.h

@@ -135,8 +135,24 @@ class TViewerPipeClient : public TActorBootstrapped<TDerived> {
             traceId = NWilson::TTraceId::FromTraceparentHeader(traceparent, TComponentTracingLevels::ProductionVerbose);
         }
         TStringBuf wantTrace = Event->Get()->Request.GetHeader("X-Want-Trace");
-        if (!traceId && FromStringWithDefault<bool>(wantTrace)) {
-            traceId = NWilson::TTraceId::NewTraceId(TComponentTracingLevels::ProductionVerbose, Max<ui32>());
+        TStringBuf traceVerbosity = Event->Get()->Request.GetHeader("X-Trace-Verbosity");
+        TStringBuf traceTTL = Event->Get()->Request.GetHeader("X-Trace-TTL");
+        if (!traceId && (FromStringWithDefault<bool>(wantTrace) || !traceVerbosity.empty() || !traceTTL.empty())) {
+            ui8 verbosity = TComponentTracingLevels::ProductionVerbose;
+            if (traceVerbosity) {
+                verbosity = FromStringWithDefault<ui8>(traceVerbosity, verbosity);
+                if (verbosity > NWilson::TTraceId::MAX_VERBOSITY) {
+                    verbosity = NWilson::TTraceId::MAX_VERBOSITY;
+                }
+            }
+            ui32 ttl = Max<ui32>();
+            if (traceTTL) {
+                ttl = FromStringWithDefault<ui32>(traceTTL, ttl);
+                if (ttl > NWilson::TTraceId::MAX_TIME_TO_LIVE) {
+                    ttl = NWilson::TTraceId::MAX_TIME_TO_LIVE;
+                }
+            }
+            traceId = NWilson::TTraceId::NewTraceId(verbosity, ttl);
         }
         if (traceId) {
             Span = {TComponentTracingLevels::THttp::TopLevel, std::move(traceId), "http", NWilson::EFlags::AUTO_END};

ydb/library/actors/wilson/wilson_trace.h

@@ -26,15 +26,19 @@ namespace NWilson {
             ui32 Raw;
         };
 
+    public:
+        static constexpr ui32 MAX_VERBOSITY = 15;
+        static constexpr ui32 MAX_TIME_TO_LIVE = 4095;
+
     private:
         TTraceId(TTrace traceId, ui64 spanId, ui8 verbosity, ui32 timeToLive)
             : TraceId(traceId)
         {
             if (timeToLive == Max<ui32>()) {
-                timeToLive = 4095;
+                timeToLive = MAX_TIME_TO_LIVE;
             }
-            Y_ABORT_UNLESS(verbosity <= 15);
-            Y_ABORT_UNLESS(timeToLive <= 4095);
+            Y_ABORT_UNLESS(verbosity <= MAX_VERBOSITY);
+            Y_ABORT_UNLESS(timeToLive <= MAX_TIME_TO_LIVE);
             SpanId = spanId;
             Verbosity = verbosity;
             TimeToLive = timeToLive;