Code improvements for ETW exporter

.github/CODEOWNERS

@@ -1,5 +1,8 @@
 # Code owners file.
 # This file controls who is tagged for review for any given pull request.
 
+# For ETW exporter
+exporters/etw/*  @reyang @maxgolov @lalitb @ThomsonTan @open-telemetry/cpp-approvers
+
 # For anything not explicitly taken by someone else:
 *       @open-telemetry/cpp-approvers

CMakeLists.txt

@@ -6,6 +6,8 @@ cmake_policy(SET CMP0057 NEW)
 
 project(opentelemetry-cpp)
 
+add_definitions(-DHAVE_CSTRING_TYPE)
+
 file(READ "${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
      OPENTELEMETRY_CPP_HEADER_VERSION_H)
 if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
@@ -87,9 +89,6 @@ if(WIN32)
   option(WITH_ETW "Whether to include the ETW Exporter in the SDK" ON)
   if(WITH_ETW)
     add_definitions(-DHAVE_MSGPACK)
-    # Option below will be removed once we donate the TraceLoggingDynamic.h to
-    # OSS
-    add_definitions(-DHAVE_NO_TLD)
   endif(WITH_ETW)
 endif(WIN32)
 
@@ -167,8 +166,8 @@ endif()
 
 list(APPEND CMAKE_PREFIX_PATH "${CMAKE_BINARY_DIR}")
 
+include(CTest)
 if(BUILD_TESTING)
-  include(CTest)
   if(EXISTS ${CMAKE_BINARY_DIR}/lib/libgtest.a)
     # Prefer GTest from build tree. GTest is not always working with
     # CMAKE_PREFIX_PATH
@@ -213,6 +212,9 @@ if(WITH_EXAMPLES)
 endif()
 add_subdirectory(ext)
 
+# Add nlohmann/json submodule to include directories
+include_directories(third_party/nlohmann-json/single_include)
+
 # Export cmake config and support find_packages(opentelemetry-cpp CONFIG) Write
 # config file for find_packages(opentelemetry-cpp CONFIG)
 set(INCLUDE_INSTALL_DIR "${CMAKE_INSTALL_INCLUDEDIR}")

CMakeSettings.json

@@ -1,108 +1,126 @@
 {
-    "configurations": [
+  "configurations": [
+    {
+      "name": "nostd-x64-Debug",
+      "generator": "Ninja",
+      "configurationType": "Debug",
+        "inheritEnvironments": [
+          "msvc_x64_x64"
+        ],
+      "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
+      "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
+      "cmakeCommandArgs": "",
+      "buildCommandArgs": "",
+      "ctestCommandArgs": "",
+      "variables": [
         {
-            "name": "nostd-x64-Debug",
-            "generator": "Ninja",
-            "configurationType": "Debug",
-            "inheritEnvironments": [ "msvc_x64_x64" ],
-            "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
-            "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
-            "cmakeCommandArgs": "",
-            "buildCommandArgs": "",
-            "ctestCommandArgs": "",
-            "variables": [
-                {
-                    "name": "WITH_OTLP",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_EXAMPLES",
-                    "value": "true",
-                    "type": "BOOL"
-                }
-            ]
+          "name": "WITH_OTLP",
+          "value": "True",
+          "type": "BOOL"
         },
         {
-            "name": "nostd-x64-Release",
-            "generator": "Ninja",
-            "configurationType": "RelWithDebInfo",
-            "inheritEnvironments": [ "msvc_x64_x64" ],
-            "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
-            "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
-            "cmakeCommandArgs": "",
-            "buildCommandArgs": "",
-            "ctestCommandArgs": "",
-            "cmakeToolchain": "",
-            "variables": [
-                {
-                    "name": "WITH_OTLP",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_EXAMPLES",
-                    "value": "true",
-                    "type": "BOOL"
-                }
-            ]
+          "name": "WITH_EXAMPLES",
+          "value": "true",
+          "type": "BOOL"
+        }
+      ]
+    },
+    {
+      "name": "nostd-x64-Release",
+      "generator": "Ninja",
+      "configurationType": "Release",
+        "inheritEnvironments": [
+          "msvc_x64_x64"
+        ],
+      "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
+      "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
+      "cmakeCommandArgs": "",
+      "buildCommandArgs": "",
+      "ctestCommandArgs": "",
+      "cmakeToolchain": "",
+      "variables": [
+        {
+          "name": "WITH_OTLP",
+          "value": "True",
+          "type": "BOOL"
+        },
+        {
+          "name": "WITH_EXAMPLES",
+          "value": "true",
+          "type": "BOOL"
+        }
+      ]
+    },
+    {
+      "name": "stdlib-x64-Debug",
+      "generator": "Ninja",
+      "configurationType": "Debug",
+      "inheritEnvironments": [
+        "msvc_x64_x64"
+      ],
+      "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
+      "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
+      "cmakeCommandArgs": "",
+      "buildCommandArgs": "",
+      "ctestCommandArgs": "",
+      "variables": [
+        {
+          "name": "WITH_STL",
+          "value": "True",
+          "type": "BOOL"
+        },
+        {
+          "name": "WITH_OTLP",
+          "value": "True",
+          "type": "BOOL"
+        },
+        {
+          "name": "WITH_EXAMPLES",
+          "value": "true",
+          "type": "BOOL"
+        },
+        {
+          "name": "WITH_PROMETHEUS",
+          "value": "True",
+          "type": "BOOL"
+        }
+      ]
+    },
+    {
+      "name": "stdlib-x64-Release",
+      "generator": "Ninja",
+      "configurationType": "Release",
+      "inheritEnvironments": [
+        "msvc_x64_x64"
+      ],
+      "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
+      "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
+      "cmakeCommandArgs": "",
+      "buildCommandArgs": "",
+      "ctestCommandArgs": "",
+      "cmakeToolchain": "",
+      "variables": [
+        {
+          "name": "WITH_STL",
+          "value": "True",
+          "type": "BOOL"
+        },
+        {
+          "name": "WITH_OTLP",
+          "value": "True",
+          "type": "BOOL"
         },
         {
-            "name": "stdlib-x64-Debug",
-            "generator": "Ninja",
-            "configurationType": "Debug",
-            "inheritEnvironments": [ "msvc_x64_x64" ],
-            "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
-            "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
-            "cmakeCommandArgs": "",
-            "buildCommandArgs": "",
-            "ctestCommandArgs": "",
-            "variables": [
-                {
-                    "name": "WITH_STL",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_OTLP",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_EXAMPLES",
-                    "value": "true",
-                    "type": "BOOL"
-                }
-            ]
+          "name": "WITH_EXAMPLES",
+          "value": "true",
+          "type": "BOOL"
         },
         {
-            "name": "stdlib-x64-Release",
-            "generator": "Ninja",
-            "configurationType": "RelWithDebInfo",
-            "inheritEnvironments": [ "msvc_x64_x64" ],
-            "buildRoot": "${projectDir}\\out\\vs2019\\${name}",
-            "installRoot": "${projectDir}\\out\\vs2019\\${name}\\install",
-            "cmakeCommandArgs": "",
-            "buildCommandArgs": "",
-            "ctestCommandArgs": "",
-            "cmakeToolchain": "",
-            "variables": [
-                {
-                    "name": "WITH_STL",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_OTLP",
-                    "value": "True",
-                    "type": "BOOL"
-                },
-                {
-                    "name": "WITH_EXAMPLES",
-                    "value": "true",
-                    "type": "BOOL"
-                }
-            ]
+          "name": "WITH_PROMETHEUS",
+          "value": "True",
+          "type": "BOOL"
         }
-    ]
+      ]
+    }
+  ]
 }

api/include/opentelemetry/common/key_value_iterable_view.h

@@ -30,10 +30,19 @@ struct is_key_value_iterable
 };
 }  // namespace detail
 
+/**
+ * @brief Container for key-value pairs that can transform every value in it to one of types
+ * listed in common::AttributeValue. It may contain value types that are not directly map'able
+ * to primitive value types. In that case the `ForEachKeyValue` method acts as a transform to
+ * convert the value type to one listed under AtributeValue (bool, int32_t, int64_t, uint32_t,
+ * uint64_t, double, nostd::string_view, or arrays of primite types). For example, if UUID,
+ * GUID, or UTF-16 string type is passed as one of values stored inside this container, the
+ * container itself may provide a custom implementation of `ForEachKeyValue` to transform the
+ * 'non-standard' type to one of the standard types.
+ */
 template <class T>
 class KeyValueIterableView final : public KeyValueIterable
 {
-  static_assert(detail::is_key_value_iterable<T>::value, "Must be a key-value iterable");
 
 public:
   explicit KeyValueIterableView(const T &container) noexcept : container_{&container} {}

api/include/opentelemetry/trace/span_context_kv_iterable.h

@@ -30,5 +30,22 @@ class SpanContextKeyValueIterable
    */
   virtual size_t size() const noexcept = 0;
 };
+
+/**
+ * @brief Null Span context that does not carry any information.
+ */
+class NullSpanContext : public SpanContextKeyValueIterable
+{
+public:
+  bool ForEachKeyValue(
+      nostd::function_ref<bool(SpanContext, const opentelemetry::common::KeyValueIterable &)>
+          callback) const noexcept override
+  {
+    return false;
+  }
+
+  size_t size() const noexcept override { return 0; };
+};
+
 }  // namespace trace
 OPENTELEMETRY_END_NAMESPACE

api/include/opentelemetry/trace/span_id.h

@@ -36,6 +36,8 @@ class SpanId final
   // Creates a SpanId with the given ID.
   explicit SpanId(nostd::span<const uint8_t, kSize> id) noexcept { memcpy(rep_, id.data(), kSize); }
 
+  explicit SpanId(const uint8_t *data) noexcept { memcpy(rep_, data, kSize); }
+
   // Populates the buffer with the lowercase base16 representation of the ID.
   void ToLowerBase16(nostd::span<char, 2 * kSize> buffer) const noexcept
   {

api/include/opentelemetry/trace/trace_id.h

@@ -42,6 +42,9 @@ class TraceId final
     memcpy(rep_, id.data(), kSize);
   }
 
+  // Creates a TraceId with the given ID.
+  explicit TraceId(const uint8_t *data) noexcept { memcpy(rep_, data, kSize); }
+
   // Populates the buffer with the lowercase base16 representation of the ID.
   void ToLowerBase16(nostd::span<char, 2 * kSize> buffer) const noexcept
   {

api/include/opentelemetry/trace/tracer.h

@@ -52,6 +52,13 @@ class Tracer
     return this->StartSpan(name, attributes, {}, options);
   }
 
+  nostd::shared_ptr<Span> StartSpan(nostd::string_view name,
+                                    const common::KeyValueIterable &attributes,
+                                    const StartSpanOptions &options = {}) noexcept
+  {
+    return this->StartSpan(name, attributes, NullSpanContext(), options);
+  }
+
   template <class T,
             class U,
             nostd::enable_if_t<common::detail::is_key_value_iterable<T>::value> * = nullptr,

api/test/nostd/string_view_test.cc

@@ -68,7 +68,7 @@ TEST(StringViewTest, SubstrPortion)
 TEST(StringViewTest, SubstrOutOfRange)
 {
   string_view s = "abc123";
-#if __EXCEPTIONS || defined(HAVE_STDLIB_CPP)
+#if __EXCEPTIONS || defined(HAVE_CPP_STDLIB)
   EXPECT_THROW(s.substr(10), std::out_of_range);
 #else
   EXPECT_DEATH({ s.substr(10); }, "");