Add language prefix to Jaeger client version tag (#35)

Signed-off-by: Isaac Hier <[email protected]>

Author: isaachier

src/jaegertracing/Constants.h.in

@@ -21,7 +21,7 @@
 
 namespace jaegertracing {
 
-static constexpr auto kJaegerClientVersion = "@PROJECT_VERSION@";
+static constexpr auto kJaegerClientVersion = "C++-@PROJECT_VERSION@";
 static constexpr auto kJaegerClientVersionTagKey = "jaeger.version";
 static constexpr auto kJaegerDebugHeader = "jaeger-debug-id";
 static constexpr auto kJaegerBaggageHeader = "jaeger-baggage";

src/jaegertracing/TracerTest.cpp

@@ -122,6 +122,17 @@ TEST(Tracer, testTracer)
     const auto tracer =
         std::static_pointer_cast<Tracer>(opentracing::Tracer::Global());
 
+    auto tagItr =
+        std::find_if(std::begin(tracer->tags()),
+                     std::end(tracer->tags()),
+                     [](const Tag& tag) {
+                         return tag.key() == kJaegerClientVersionTagKey;
+                     });
+    ASSERT_NE(std::end(tracer->tags()), tagItr);
+    ASSERT_TRUE(tagItr->value().is<const char*>());
+    ASSERT_EQ("C++-",
+        static_cast<std::string>(tagItr->value().get<const char*>()).substr(0, 4));
+
     opentracing::StartSpanOptions options;
     options.tags.push_back({ "tag-key", 1.23 });