Merge pull request #35 from lightstep/jmacd/relationship_ref

Encode span relationships in the appropriate Span field.

Author: jmacd

src/c++11/impl.cc

@@ -231,15 +231,17 @@ void SpanImpl::FinishSpan(SpanFinishOptions opts) {
   auto tags = span.mutable_tags();
 
   if (ref_.valid()) {
-    // Note: Converting span_id to a hex string here is necessary
-    // because the Proto->Thrift conversion does not know to format
-    // int-valued tags as hex-valued, yet the string value for
-    // parent_span_guid is interpreted as a hex value downstream.
-    //
-    // TODO: The protocol supports encoding relationships directly.
-    // switch to the native representation after validating the
-    // feature in the collector.
-    *tags->Add() = util::make_kv(ParentSpanGUIDKey, uint64ToHex(ref_.referenced().span_id()));
+    auto refs = span.mutable_references();
+    auto ref = refs->Add();
+    ref->mutable_span_context()->set_span_id(ref_.referenced().span_id());
+    switch (ref_.type()) {
+    case FollowsFromRef:
+      ref->set_relationship(collector::Reference::FOLLOWS_FROM);
+      break;
+    default:
+      ref->set_relationship(collector::Reference::CHILD_OF);
+      break;
+    }
   }
 
   {

src/c++11/lightstep/propagation.h

@@ -109,6 +109,9 @@ class SpanReference : public SpanStartOption {
   // This is a no-op if the referenced context is not valid.
   virtual void Apply(SpanImpl *span) const override;
 
+  // Return the relationship type of this reference.
+  SpanReferenceType type() const { return type_; }
+
 private:
   SpanReferenceType type_;
   SpanContext referenced_;

test/c++11/tracer_test.cc

@@ -34,9 +34,9 @@ int main() {
 
     TracerOptions topts;
 
-    topts.access_token = "DEVELOPMENT_TOKEN_jmacd";
+    topts.access_token = "3e5170e56cc4f4b2c94695a13ddf23d1";
     topts.collector_host = "localhost";
-    topts.collector_port = 9998;
+    topts.collector_port = 9997;
     topts.collector_encryption = "";
 
     BasicRecorderOptions bopts;
@@ -56,13 +56,6 @@ int main() {
     auto cspan = Tracer::Global().StartSpan("span/child", { ChildOf(parent) });
     cspan.Finish();
 
-    auto child = cspan.context();
-
-    // if (child.parent_span_id() == 0 ||
-    // 	child.parent_span_id() != parent.span_id()) {
-    //   throw error("parent/child span_id mismatch");
-    // }
-	
     Tracer::Global().impl()->Flush();
   } catch (std::exception &e) {
     std::cerr << "Exception! " << e.what() << std::endl;