ceph/src/jaegertracing/opentelemetry-cpp/examples/http/tracer_common.h

   1 // Copyright The OpenTelemetry Authors
   2 // SPDX-License-Identifier: Apache-2.0
   3
   4 #pragma once
   5 #include "opentelemetry/exporters/ostream/span_exporter.h"
   6 #include "opentelemetry/sdk/trace/simple_processor.h"
   7 #include "opentelemetry/sdk/trace/tracer_provider.h"
   8 #include "opentelemetry/trace/provider.h"
   9
  10 #include "opentelemetry/context/propagation/global_propagator.h"
  11 #include "opentelemetry/context/propagation/text_map_propagator.h"
  12 #include "opentelemetry/trace/propagation/http_trace_context.h"
  13
  14 #include <cstring>
  15 #include <iostream>
  16 #include <vector>
  17 #include "opentelemetry/ext/http/client/http_client.h"
  18 #include "opentelemetry/nostd/shared_ptr.h"
  19
  20 namespace
  21 {
  22
  23 template <typename T>
  24 class HttpTextMapCarrier : public opentelemetry::context::propagation::TextMapCarrier
  25 {
  26 public:
  27   HttpTextMapCarrier<T>(T &headers) : headers_(headers) {}
  28   HttpTextMapCarrier() = default;
  29   virtual opentelemetry::nostd::string_view Get(
  30       opentelemetry::nostd::string_view key) const noexcept override
  31   {
  32     std::string key_to_compare = key.data();
  33     // Header's first letter seems to be  automatically capitaliazed by our test http-server, so
  34     // compare accordingly.
  35     if (key == opentelemetry::trace::propagation::kTraceParent)
  36     {
  37       key_to_compare = "Traceparent";
  38     }
  39     else if (key == opentelemetry::trace::propagation::kTraceState)
  40     {
  41       key_to_compare = "Tracestate";
  42     }
  43     auto it = headers_.find(key_to_compare);
  44     if (it != headers_.end())
  45     {
  46       return it->second;
  47     }
  48     return "";
  49   }
  50
  51   virtual void Set(opentelemetry::nostd::string_view key,
  52                    opentelemetry::nostd::string_view value) noexcept override
  53   {
  54     headers_.insert(std::pair<std::string, std::string>(std::string(key), std::string(value)));
  55   }
  56
  57   T headers_;
  58 };
  59
  60 void initTracer()
  61 {
  62   auto exporter = std::unique_ptr<opentelemetry::sdk::trace::SpanExporter>(
  63       new opentelemetry::exporter::trace::OStreamSpanExporter);
  64   auto processor = std::unique_ptr<opentelemetry::sdk::trace::SpanProcessor>(
  65       new opentelemetry::sdk::trace::SimpleSpanProcessor(std::move(exporter)));
  66   std::vector<std::unique_ptr<opentelemetry::sdk::trace::SpanProcessor>> processors;
  67   processors.push_back(std::move(processor));
  68   // Default is an always-on sampler.
  69   auto context  = std::make_shared<opentelemetry::sdk::trace::TracerContext>(std::move(processors));
  70   auto provider = opentelemetry::nostd::shared_ptr<opentelemetry::trace::TracerProvider>(
  71       new opentelemetry::sdk::trace::TracerProvider(context));
  72   // Set the global trace provider
  73   opentelemetry::trace::Provider::SetTracerProvider(provider);
  74
  75   // set global propagator
  76   opentelemetry::context::propagation::GlobalTextMapPropagator::SetGlobalPropagator(
  77       opentelemetry::nostd::shared_ptr<opentelemetry::context::propagation::TextMapPropagator>(
  78           new opentelemetry::trace::propagation::HttpTraceContext()));
  79 }
  80
  81 opentelemetry::nostd::shared_ptr<opentelemetry::trace::Tracer> get_tracer(std::string tracer_name)
  82 {
  83   auto provider = opentelemetry::trace::Provider::GetTracerProvider();
  84   return provider->GetTracer(tracer_name);
  85 }
  86
  87 }  // namespace