xray tracer: set subsegment type for child spans (#2)

* xray tracer: set subsegment type for child spans

Signed-off-by: Rex Chang <58710378+rexnp@users.noreply.github.com>

* adds test coverage

Signed-off-by: Rex Chang <58710378+rexnp@users.noreply.github.com>

source/extensions/tracers/xray/daemon.proto

@@ -43,6 +43,9 @@ message Segment {
   }
   // Object containing one or more fields that X-Ray indexes for use with filter expressions.
   map<string, string> annotations = 8;
+  // Set type to "subsegment" when sending a child span so Xray treats it as a subsegment.
+  // https://docs.aws.amazon.com/xray/latest/devguide/xray-api-segmentdocuments.html#api-segmentdocuments-subsegments
+  string type = 14;
 }
 
 message Header {

source/extensions/tracers/xray/tracer.cc

@@ -71,7 +71,9 @@ void Span::finishSpan() {
   s.set_error(clientError());
   s.set_fault(serverError());
   s.set_throttle(isThrottled());
-
+  if (type() == Subsegment) {
+    s.set_type(std::string(Subsegment));
+  }
   auto* aws = s.mutable_aws()->mutable_fields();
   for (const auto& field : aws_metadata_) {
     aws->insert({field.first, field.second});
@@ -115,6 +117,7 @@ Tracing::SpanPtr Span::spawnChild(const Tracing::Config& config, const std::stri
   child_span->setParentId(id());
   child_span->setTraceId(traceId());
   child_span->setSampled(sampled());
+  child_span->setType(Subsegment);
   return child_span;
 }
 

source/extensions/tracers/xray/tracer.h

@@ -26,6 +26,7 @@ namespace Tracers {
 namespace XRay {
 
 constexpr auto XRayTraceHeader = "x-amzn-trace-id";
+constexpr absl::string_view Subsegment = "subsegment";
 
 class Span : public Tracing::Span, Logger::Loggable<Logger::Id::config> {
 public:
@@ -101,6 +102,12 @@ class Span : public Tracing::Span, Logger::Loggable<Logger::Id::config> {
     parent_segment_id_ = std::string(parent_segment_id);
   }
 
+  /**
+   * Sets the type of the Span. In Xray, an independent subsegment has a type of ``subsegment``.
+   * https://docs.aws.amazon.com/xray/latest/devguide/xray-api-segmentdocuments.html#api-segmentdocuments-subsegments
+   */
+  void setType(absl::string_view type) { type_ = std::string(type); }
+
   /**
    * Sets the aws metadata field of the Span.
    */
@@ -156,6 +163,11 @@ class Span : public Tracing::Span, Logger::Loggable<Logger::Id::config> {
    */
   const std::string& direction() const { return direction_; }
 
+  /**
+   * Gets this Span's type.
+   */
+  const std::string& type() const { return type_; }
+
   /**
    * Gets this Span's name.
    */
@@ -216,6 +228,7 @@ class Span : public Tracing::Span, Logger::Loggable<Logger::Id::config> {
   std::string parent_segment_id_;
   std::string name_;
   std::string origin_;
+  std::string type_;
   absl::flat_hash_map<std::string, ProtobufWkt::Value> aws_metadata_;
   absl::flat_hash_map<std::string, ProtobufWkt::Value> http_request_annotations_;
   absl::flat_hash_map<std::string, ProtobufWkt::Value> http_response_annotations_;

test/extensions/tracers/xray/tracer_test.cc

@@ -97,6 +97,7 @@ TEST_F(XRayTracerTest, SerializeSpanTest) {
     EXPECT_FALSE(s.id().empty());
     EXPECT_EQ(2, s.annotations().size());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_FALSE(s.fault());    /*server error*/
     EXPECT_FALSE(s.error());    /*client error*/
     EXPECT_FALSE(s.throttle()); /*request throttled*/
@@ -142,6 +143,7 @@ TEST_F(XRayTracerTest, SerializeSpanTestServerError) {
     EXPECT_FALSE(s.trace_id().empty());
     EXPECT_FALSE(s.id().empty());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_TRUE(s.fault());  /*server error*/
     EXPECT_FALSE(s.error()); /*client error*/
     EXPECT_EQ(expected_status_code,
@@ -175,6 +177,7 @@ TEST_F(XRayTracerTest, SerializeSpanTestClientError) {
     EXPECT_FALSE(s.trace_id().empty());
     EXPECT_FALSE(s.id().empty());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_FALSE(s.fault());    /*server error*/
     EXPECT_TRUE(s.error());     /*client error*/
     EXPECT_FALSE(s.throttle()); /*request throttled*/
@@ -208,6 +211,7 @@ TEST_F(XRayTracerTest, SerializeSpanTestClientErrorWithThrottle) {
     EXPECT_FALSE(s.trace_id().empty());
     EXPECT_FALSE(s.id().empty());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_FALSE(s.fault());   /*server error*/
     EXPECT_TRUE(s.error());    /*client error*/
     EXPECT_TRUE(s.throttle()); /*request throttled*/
@@ -239,6 +243,7 @@ TEST_F(XRayTracerTest, SerializeSpanTestWithEmptyValue) {
     EXPECT_FALSE(s.trace_id().empty());
     EXPECT_FALSE(s.id().empty());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_FALSE(s.http().request().fields().contains(Tracing::Tags::get().Status));
   };
 
@@ -270,6 +275,7 @@ TEST_F(XRayTracerTest, SerializeSpanTestWithStatusCodeNotANumber) {
     EXPECT_FALSE(s.trace_id().empty());
     EXPECT_FALSE(s.id().empty());
     EXPECT_TRUE(s.parent_id().empty());
+    EXPECT_TRUE(s.type().empty());
     EXPECT_FALSE(s.http().request().fields().contains(Tracing::Tags::get().Status));
     EXPECT_FALSE(s.http().request().fields().contains("content_length"));
   };
@@ -347,6 +353,8 @@ TEST_F(XRayTracerTest, ChildSpanHasParentInfo) {
     // Hex encoded 64 bit identifier
     EXPECT_STREQ("00000000000003e7", s.parent_id().c_str());
     EXPECT_EQ(expected_->span_name, s.name().c_str());
+    EXPECT_TRUE(xray_parent_span->type().empty());
+    EXPECT_EQ(Subsegment, s.type().c_str());
     EXPECT_STREQ(xray_parent_span->traceId().c_str(), s.trace_id().c_str());
     EXPECT_STREQ("0000003d25bebe62", s.id().c_str());
   };