automatic timestamp injection to the trace data (#46)

* automatic timestamp injection to the trace data

* add timepoint class and allow to accept arbitary time

* delete component id limitation

Author: Shikugawa

README.md

@@ -66,7 +66,7 @@ TracerPtr tracer = createInsecureGrpcTracer(tracer_config);
 
 #### Fetch propagated span
 
-cpp2sky supports only HTTP tracer now. 
+cpp2sky supports only HTTP tracer now.
 Tracing span will be delivered from `sw8` and `sw8-x` HTTP headers. For more detail, please visit [here](https://github.com/apache/skywalking/blob/08781b41a8255bcceebb3287364c81745a04bec6/docs/en/protocols/Skywalking-Cross-Process-Propagation-Headers-Protocol-v3.md)
 Then, you can create propagated span object by decoding these items.
 
@@ -100,16 +100,16 @@ CurrentSegmentSpanPtr current_span = current_segment->createCurrentSegmentSpan(c
 
 #### Send segment to OAP
 
-Note that SegmentContextPtr is unique pointer. So when you'd like to send data, you must move it and don't refer after sending, 
+Note that SegmentContextPtr is unique pointer. So when you'd like to send data, you must move it and don't refer after sending,
 to avoid undefined behavior.
 
 ```cpp
 SegmentContextPtr current_segment = createSegmentContext(config);
 CurrentSegmentSpanPtr current_span = current_segment->createCurrentSegmentRootSpan();
 
+current_span->startSpan();
 current_span->setOperationName("sample_workload");
-current_span->setStartTime(...);
-current_span->setEndTime(...);
+current_span->endSpan();
 
 tracer->sendSegment(std::move(current_segment));
 ```

cpp2sky/BUILD

@@ -48,6 +48,12 @@ cc_library(
   visibility = ["//visibility:public"],
 )
 
+cc_library(
+  name = "time_interface",
+  hdrs = ["time.h"],
+  visibility = ["//visibility:public"],
+)
+
 cc_library(
   name = "cpp2sky_interface",
   hdrs = [
@@ -61,4 +67,4 @@ cc_library(
     "@skywalking_data_collect_protocol//language-agent:tracing_protocol_cc_grpc",
   ],
   visibility = ["//visibility:public"],
-) 
+)

cpp2sky/segment_context.h

@@ -20,6 +20,7 @@
 
 #include "cpp2sky/config.h"
 #include "cpp2sky/propagation.h"
+#include "cpp2sky/time.h"
 #include "language-agent/Tracing.pb.h"
 
 namespace cpp2sky {
@@ -33,11 +34,73 @@ class CurrentSegmentSpan {
    */
   virtual SpanObject createSpanObject() = 0;
 
+  /**
+   * Get sampling status. If true, spans belongs to this segment will be sent to
+   * OAP.
+   */
+  virtual bool samplingStatus() const = 0;
+
   /**
    * Get span ID.
    */
   virtual int32_t spanId() const = 0;
 
+  /**
+   * Get parent span ID.
+   */
+  virtual int32_t parentSpanId() const = 0;
+
+  /**
+   * Get start time.
+   */
+  virtual int64_t startTime() const = 0;
+
+  /**
+   * Get end time.
+   */
+  virtual int64_t endTime() const = 0;
+
+  /**
+   * Get peer address.
+   */
+  virtual const std::string& peer() const = 0;
+
+  /**
+   * Get span type.
+   */
+  virtual SpanType spanType() const = 0;
+
+  /**
+   * Get span layer.
+   */
+  virtual SpanLayer spanLayer() const = 0;
+
+  /**
+   * Get error occurred or not.
+   */
+  virtual bool errorStatus() const = 0;
+
+  /**
+   * Enable to skip analysis or not.
+   */
+  virtual bool skipAnalysis() const = 0;
+
+  /**
+   * Get component ID.
+   */
+  virtual int32_t componentId() const = 0;
+
+  /**
+   * Get tags.
+   */
+  virtual const std::vector<std::pair<std::string, std::string>>& tags()
+      const = 0;
+
+  /**
+   * Get logs.
+   */
+  virtual const std::vector<Log>& logs() const = 0;
+
   /**
    * Get operation name.
    */
@@ -51,17 +114,21 @@ class CurrentSegmentSpan {
   /**
    * Set start time to calculate execution time.
    */
-  virtual void setStartTime(int64_t start_time) = 0;
+  virtual void startSpan() = 0;
+  virtual void startSpan(TimePoint<SystemTime> current_time) = 0;
+  virtual void startSpan(TimePoint<SteadyTime> current_time) = 0;
 
   /**
    * Set end time to calculate execution time.
    */
-  virtual void setEndTime(int64_t end_time) = 0;
+  virtual void endSpan() = 0;
+  virtual void endSpan(TimePoint<SystemTime> current_time) = 0;
+  virtual void endSpan(TimePoint<SteadyTime> current_time) = 0;
 
   /**
    * Set operation name for this span (lvalue)
    */
-  virtual void setOperationName(std::string& operation_name) = 0;
+  virtual void setOperationName(const std::string& operation_name) = 0;
 
   /**
    * Set operation name for this span (rvalue)
@@ -71,7 +138,7 @@ class CurrentSegmentSpan {
   /**
    * Set peer address for this span (lvalue)
    */
-  virtual void setPeer(std::string& remote_address) = 0;
+  virtual void setPeer(const std::string& remote_address) = 0;
 
   /**
    * Set peer address for this span (rvalue)
@@ -104,7 +171,7 @@ class CurrentSegmentSpan {
   /**
    * Set tag to current span. (lvalue)
    */
-  virtual void addTag(std::string& key, std::string& value) = 0;
+  virtual void addTag(const std::string& key, const std::string& value) = 0;
 
   /**
    * Set tag to current span. (rvalue)
@@ -113,8 +180,26 @@ class CurrentSegmentSpan {
 
   /**
    * Add log related with current span.
+   * @param set_time To determine whether to set actual time or not.
+   * This value is introduced for unit-test.
+   */
+  virtual void addLog(const std::string& key, const std::string& value,
+                      bool set_time = true) = 0;
+
+  /**
+   * Set component ID.
+   */
+  virtual void setComponentId(int32_t component_id) = 0;
+
+  /**
+   * This span had finished or not.
+   */
+  virtual bool finished() const = 0;
+
+  /**
+   * Change sampling status. If true, it will be sampled.
    */
-  virtual void addLog(int64_t time, std::string& key, std::string& value) = 0;
+  virtual void setSamplingStatus(bool do_sample) = 0;
 };
 
 using CurrentSegmentSpanPtr = std::shared_ptr<CurrentSegmentSpan>;

cpp2sky/time.h

@@ -0,0 +1,66 @@
+// Copyright 2020 SkyAPM
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include <chrono>
+
+namespace cpp2sky {
+
+using SystemTime = std::chrono::system_clock::time_point;
+using SteadyTime = std::chrono::steady_clock::time_point;
+
+template <class T>
+static constexpr bool false_v = false;
+
+template <class T>
+class TimePoint {
+  static_assert(false_v<T>, "Invalid time type");
+};
+
+template <>
+class TimePoint<SystemTime> {
+ public:
+  TimePoint(SystemTime point) : point_(point) {}
+  TimePoint() { point_ = std::chrono::system_clock::now(); }
+
+  // Fetch timestamp with millisecond resolution
+  int64_t fetch() {
+    return std::chrono::duration_cast<std::chrono::milliseconds>(
+               point_.time_since_epoch())
+        .count();
+  }
+
+ private:
+  SystemTime point_;
+};
+
+template <>
+class TimePoint<SteadyTime> {
+ public:
+  TimePoint(SteadyTime point) : point_(point) {}
+  TimePoint() { point_ = std::chrono::steady_clock::now(); }
+
+  // Fetch timestamp with millisecond resolution
+  int64_t fetch() {
+    return std::chrono::duration_cast<std::chrono::milliseconds>(
+               point_.time_since_epoch())
+        .count();
+  }
+
+ private:
+  SteadyTime point_;
+};
+
+}  // namespace cpp2sky

example/sample.cc

@@ -48,9 +48,9 @@ int main() {
     auto current_span = current_segment->createCurrentSegmentRootSpan();
 
     // 4. Set info
+    current_span->startSpan();
     current_span->setOperationName("/ping");
-    current_span->setStartTime(now());
-    current_span->setEndTime(now());
+    current_span->endSpan();
 
     // 5. Send span data
     tracer->sendSegment(std::move(current_segment));

example/sample_client.cc

@@ -45,15 +45,15 @@ int main() {
   auto current_span = current_segment->createCurrentSegmentRootSpan();
 
   // 4. Set info
+  current_span->startSpan();
   current_span->setOperationName("/ping");
-  current_span->setStartTime(now());
 
   httplib::Client cli("remote", 8082);
   httplib::Headers headers = {{"sw8", current_segment->createSW8HeaderValue(
                                           current_span, "remote:8082")}};
   auto res = cli.Get("/ping", headers);
 
-  current_span->setEndTime(now());
+  current_span->endSpan();
 
   // 5. Send span data
   tracer->sendSegment(std::move(current_segment));

source/BUILD

@@ -23,6 +23,7 @@ cc_library(
     "//cpp2sky:segment_context_interface",
     "//cpp2sky:propagation_interface",
     "//cpp2sky:tracer_interface",
+    "//cpp2sky:time_interface",
     "//source/utils:util_lib",
   ],
   visibility = ["//visibility:public"],