Merge branch 'master' into zpages-README

.bazelversion

@@ -1 +1 @@
-3.2.0
+3.3.0

.github/.codecov.yaml

@@ -0,0 +1,28 @@
+codecov:
+  require_ci_to_pass: yes
+  max_report_age: off
+
+coverage:
+  precision: 2
+  round: down
+  range: "80...100"
+
+parsers:
+  gcov:
+    branch_detection:
+      conditional: yes
+      loop: yes
+      method: no
+      macro: no
+
+comment:
+  layout: "reach,diff,flags,tree"
+  behavior: default
+  require_changes: no
+
+# Relative file path fixing.
+# CI file paths must match Git file paths.
+# This fix removes the "/home/runner/" prefix 
+# to coverage report file paths.
+fixes:
+  - "/home/runner/::"

.github/workflows/ci.yml

@@ -182,3 +182,19 @@ jobs:
         ./ci/setup_windows_ci_environment.ps1
     - name: run tests
       run: ./ci/do_ci.ps1 cmake.test_example_plugin
+
+  code_coverage:
+    name: Code coverage
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: setup
+      run: |
+        sudo ./ci/setup_cmake.sh
+        sudo ./ci/setup_ci_environment.sh
+    - name: run tests and generate report
+      run: ./ci/do_ci.sh code.coverage
+    - name: upload report
+      uses: codecov/codecov-action@v1
+      with:
+        file: /home/runner/build/coverage.info

CMakeLists.txt

@@ -23,9 +23,9 @@ include(CTest)
 find_package(Threads)
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
-  # Options for Visual C++ compiler:
-  # /Zc:__cplusplus - report an updated value for recent C++ language standards.
-  # Without this option MSVC returns the value of __cplusplus="199711L"
+  # Options for Visual C++ compiler: /Zc:__cplusplus - report an updated value
+  # for recent C++ language standards. Without this option MSVC returns the
+  # value of __cplusplus="199711L"
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /Zc:__cplusplus")
 endif()
 

api/include/opentelemetry/plugin/factory.h

@@ -36,8 +36,9 @@ class Factory final
    * @param error_message on failure this will contain an error message.
    * @return a Tracer on success or nullptr on failure.
    */
-  std::shared_ptr<Tracer> MakeTracer(nostd::string_view tracer_config,
-                                     std::string &error_message) const noexcept
+  std::shared_ptr<opentelemetry::trace::Tracer> MakeTracer(nostd::string_view tracer_config,
+                                                           std::string &error_message) const
+      noexcept
   {
     nostd::unique_ptr<char[]> plugin_error_message;
     auto tracer_handle = factory_impl_->MakeTracerHandle(tracer_config, plugin_error_message);
@@ -46,8 +47,8 @@ class Factory final
       detail::CopyErrorMessage(plugin_error_message.get(), error_message);
       return nullptr;
     }
-    return std::shared_ptr<Tracer>{new (std::nothrow)
-                                       Tracer{library_handle_, std::move(tracer_handle)}};
+    return std::shared_ptr<opentelemetry::trace::Tracer>{
+        new (std::nothrow) Tracer{library_handle_, std::move(tracer_handle)}};
   }
 
 private:

api/include/opentelemetry/plugin/tracer.h

@@ -18,6 +18,11 @@ class Span final : public trace::Span
   {}
 
   // trace::Span
+  void SetAttribute(nostd::string_view name, const common::AttributeValue &&value) noexcept override
+  {
+    span_->SetAttribute(name, std::move(value));
+  }
+
   void AddEvent(nostd::string_view name) noexcept override { span_->AddEvent(name); }
 
   void AddEvent(nostd::string_view name, core::SystemTimestamp timestamp) noexcept override
@@ -61,9 +66,10 @@ class Tracer final : public trace::Tracer, public std::enable_shared_from_this<T
   // trace::Tracer
   nostd::unique_ptr<trace::Span> StartSpan(
       nostd::string_view name,
+      const trace::KeyValueIterable &attributes,
       const trace::StartSpanOptions &options = {}) noexcept override
   {
-    auto span = tracer_handle_->tracer().StartSpan(name, options);
+    auto span = tracer_handle_->tracer().StartSpan(name, attributes, options);
     if (span == nullptr)
     {
       return nullptr;

api/include/opentelemetry/trace/noop.h

@@ -24,6 +24,10 @@ class NoopSpan final : public Span
 public:
   explicit NoopSpan(const std::shared_ptr<Tracer> &tracer) noexcept : tracer_{tracer} {}
 
+  void SetAttribute(nostd::string_view /*key*/,
+                    const common::AttributeValue && /*value*/) noexcept override
+  {}
+
   void AddEvent(nostd::string_view /*name*/) noexcept override {}
 
   void AddEvent(nostd::string_view /*name*/, core::SystemTimestamp /*timestamp*/) noexcept override
@@ -56,6 +60,7 @@ class NoopTracer final : public Tracer, public std::enable_shared_from_this<Noop
 public:
   // Tracer
   nostd::unique_ptr<Span> StartSpan(nostd::string_view /*name*/,
+                                    const KeyValueIterable & /*attributes*/,
                                     const StartSpanOptions & /*options*/) noexcept override
   {
     return nostd::unique_ptr<Span>{new (std::nothrow) NoopSpan{this->shared_from_this()}};

api/include/opentelemetry/trace/span.h

@@ -2,6 +2,7 @@
 
 #include <cstdint>
 
+#include "opentelemetry/common/attribute_value.h"
 #include "opentelemetry/core/timestamp.h"
 #include "opentelemetry/nostd/span.h"
 #include "opentelemetry/nostd/string_view.h"
@@ -40,7 +41,6 @@ struct StartSpanOptions
   // Span(Context?) parent;
   // SpanContext remote_parent;
   // Links
-  // Attributes
   SpanKind kind = SpanKind::kInternal;
 };
 /**
@@ -74,13 +74,10 @@ class Span
   Span &operator=(const Span &) = delete;
   Span &operator=(Span &&) = delete;
 
-  // TODO
   // Sets an attribute on the Span. If the Span previously contained a mapping for
   // the key, the old value is replaced.
-  //
-  // If an empty string is used as the value, the attribute will be silently
-  // dropped. Note: this behavior could change in the future.
-  // virtual void SetAttribute(nostd::string_view key, AttributeValue&& value) = 0;
+  virtual void SetAttribute(nostd::string_view key,
+                            const common::AttributeValue &&value) noexcept = 0;
 
   // Adds an event to the Span.
   virtual void AddEvent(nostd::string_view name) noexcept = 0;

api/include/opentelemetry/trace/tracer.h

@@ -22,10 +22,41 @@ class Tracer
   virtual ~Tracer() = default;
   /**
    * Starts a span.
+   *
+   * Optionally sets attributes at Span creation from the given key/value pairs.
+   *
+   * Attributes will be processed in order, previous attributes with the same
+   * key will be overwritten.
    */
   virtual nostd::unique_ptr<Span> StartSpan(nostd::string_view name,
+                                            const KeyValueIterable &attributes,
                                             const StartSpanOptions &options = {}) noexcept = 0;
 
+  nostd::unique_ptr<Span> StartSpan(nostd::string_view name,
+                                    const StartSpanOptions &options = {}) noexcept
+  {
+    return this->StartSpan(name, {}, options);
+  }
+
+  template <class T, nostd::enable_if_t<detail::is_key_value_iterable<T>::value> * = nullptr>
+  nostd::unique_ptr<Span> StartSpan(nostd::string_view name,
+                                    const T &attributes,
+                                    const StartSpanOptions &options = {}) noexcept
+  {
+    return this->StartSpan(name, KeyValueIterableView<T>(attributes), options);
+  }
+
+  nostd::unique_ptr<Span> StartSpan(
+      nostd::string_view name,
+      std::initializer_list<std::pair<nostd::string_view, common::AttributeValue>> attributes,
+      const StartSpanOptions &options = {}) noexcept
+  {
+    return this->StartSpan(name,
+                           nostd::span<const std::pair<nostd::string_view, common::AttributeValue>>{
+                               attributes.begin(), attributes.end()},
+                           options);
+  }
+
   /**
    * Force any buffered spans to flush.
    * @param timeout to complete the flush

ci/README.md

@@ -13,6 +13,7 @@ CI tests can be run on docker by invoking the script `./ci/run_docker.sh ./ci/do
 * `bazel.tsan`: build bazel targets and run tests with ThreadSanitizer.
 * `benchmark`: run all benchmarks.
 * `format`: use `tools/format.sh` to enforce text formatting.
+* `code.coverage`: build cmake targets and run tests. Then upload coverage report to [codecov.io](https://codecov.io/).
 
 Additionally, `./ci/run_docker.sh` can be invoked with no arguments to get a docker shell where tests
 can be run manually.

ci/do_ci.sh

@@ -116,6 +116,16 @@ elif [[ "$1" == "format" ]]; then
     exit 1
   fi
   exit 0
+elif [[ "$1" == "code.coverage" ]]; then
+  cd "${BUILD_DIR}"
+  rm -rf *
+  cmake -DCMAKE_BUILD_TYPE=Debug  \
+        -DCMAKE_CXX_FLAGS="-Werror --coverage" \
+        "${SRC_DIR}"
+  make
+  make test
+  lcov --directory $PWD --capture --output-file coverage.info
+  exit 0
 fi
 
 echo "Invalid do_ci.sh target, see ci/README.md for valid targets."

ci/setup_ci_environment.sh

@@ -7,3 +7,4 @@ apt-get install --no-install-recommends --no-install-suggests -y \
                 ca-certificates \
                 wget \
                 git
+apt-get install -y lcov

examples/plugin/plugin/tracer.cc

@@ -2,9 +2,10 @@
 
 #include <iostream>
 
-namespace nostd = opentelemetry::nostd;
-namespace core  = opentelemetry::core;
-namespace trace = opentelemetry::trace;
+namespace nostd  = opentelemetry::nostd;
+namespace common = opentelemetry::common;
+namespace core   = opentelemetry::core;
+namespace trace  = opentelemetry::trace;
 
 namespace
 {
@@ -13,6 +14,7 @@ class Span final : public trace::Span
 public:
   Span(std::shared_ptr<Tracer> &&tracer,
        nostd::string_view name,
+       const opentelemetry::trace::KeyValueIterable & /*attributes*/,
        const trace::StartSpanOptions & /*options*/) noexcept
       : tracer_{std::move(tracer)}, name_{name}
   {
@@ -22,6 +24,10 @@ class Span final : public trace::Span
   ~Span() { std::cout << "~Span\n"; }
 
   // opentelemetry::trace::Span
+  void SetAttribute(nostd::string_view /*name*/,
+                    const common::AttributeValue && /*value*/) noexcept override
+  {}
+
   void AddEvent(nostd::string_view /*name*/) noexcept override {}
 
   void AddEvent(nostd::string_view /*name*/, core::SystemTimestamp /*timestamp*/) noexcept override
@@ -52,9 +58,11 @@ class Span final : public trace::Span
 
 Tracer::Tracer(nostd::string_view /*output*/) {}
 
-nostd::unique_ptr<trace::Span> Tracer::StartSpan(nostd::string_view name,
-                                                 const trace::StartSpanOptions &options) noexcept
+nostd::unique_ptr<trace::Span> Tracer::StartSpan(
+    nostd::string_view name,
+    const opentelemetry::trace::KeyValueIterable &attributes,
+    const trace::StartSpanOptions &options) noexcept
 {
   return nostd::unique_ptr<opentelemetry::trace::Span>{
-      new (std::nothrow) Span{this->shared_from_this(), name, options}};
+      new (std::nothrow) Span{this->shared_from_this(), name, attributes, options}};
 }

examples/plugin/plugin/tracer.h

@@ -13,7 +13,8 @@ class Tracer final : public opentelemetry::trace::Tracer,
   // opentelemetry::trace::Tracer
   opentelemetry::nostd::unique_ptr<opentelemetry::trace::Span> StartSpan(
       opentelemetry::nostd::string_view name,
-      const opentelemetry::trace::StartSpanOptions &options) noexcept override;
+      const opentelemetry::trace::KeyValueIterable & /*attributes*/,
+      const opentelemetry::trace::StartSpanOptions & /*options */) noexcept override;
 
   void ForceFlushWithMicroseconds(uint64_t /*timeout*/) noexcept override {}
 

examples/simple/README.md

@@ -0,0 +1,10 @@
+
+# Simple Trace Example
+
+In this example, the application in `main.cc` initializes and registers a tracer
+provider from the [OpenTelemetry SDK](https://github.com/open-telemetry/opentelemetry-cpp).
+The application then calls a `foo_library` which has been instrumented using
+the [OpenTelemetry API](https://github.com/open-telemetry/opentelemetry-cpp/tree/master/api).
+Resulting telemetry is directed to stdout through a custom exporter.
+
+See [CONTRIBUTING.md](../../CONTRIBUTING.md) for instructions on building and running the example.

examples/simple/main.cc

@@ -15,14 +15,14 @@ void initTracer()
   auto processor = std::shared_ptr<sdktrace::SpanProcessor>(
       new sdktrace::SimpleSpanProcessor(std::move(exporter)));
   auto provider = nostd::shared_ptr<trace::TracerProvider>(new sdktrace::TracerProvider(processor));
+  // Set the global trace provider
   trace::Provider::SetTracerProvider(provider);
 }
 }  // namespace
 
 int main()
 {
-  // Removing this line will leave OT initialized with the default noop
-  // tracer, thus being effectively deactivated.
+  // Removing this line will leave the default noop TracerProvider in place.
   initTracer();
 
   foo_library();

sdk/include/opentelemetry/sdk/trace/recordable.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "opentelemetry/common/attribute_value.h"
 #include "opentelemetry/core/timestamp.h"
 #include "opentelemetry/nostd/string_view.h"
 #include "opentelemetry/trace/canonical_code.h"
@@ -33,6 +34,14 @@ class Recordable
                       opentelemetry::trace::SpanId span_id,
                       opentelemetry::trace::SpanId parent_span_id) noexcept = 0;
 
+  /**
+   * Set an attribute of a span.
+   * @param name the name of the attribute
+   * @param value the attribute value
+   */
+  virtual void SetAttribute(nostd::string_view key,
+                            const opentelemetry::common::AttributeValue &&value) noexcept = 0;
+
   /**
    * Add an event to a span.
    * @param name the name of the event