Merge branch 'main' into fix_ci_iwyu

.github/workflows/ci.yml

@@ -29,25 +29,25 @@ jobs:
         ./ci/do_ci.sh cmake.test
 
   cmake_gcc_maintainer_sync_test:
-    name: CMake gcc 13 (maintainer mode, sync)
-    runs-on: ubuntu-latest
+    name: CMake gcc 14 (maintainer mode, sync)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
         PROTOBUF_VERSION: 21.12
       run: |
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake gcc (maintainer mode, sync)
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
       run: |
         ./ci/do_ci.sh cmake.maintainer.sync.test
     - name: generate test cert
@@ -61,25 +61,25 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_gcc_maintainer_async_test:
-    name: CMake gcc 13 (maintainer mode, async)
-    runs-on: ubuntu-latest
+    name: CMake gcc 14 (maintainer mode, async)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
         PROTOBUF_VERSION: 21.12
       run: |
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake gcc (maintainer mode, async)
       env:
-        CC: /usr/bin/gcc-13
-        CXX: /usr/bin/g++-13
+        CC: /usr/bin/gcc-14
+        CXX: /usr/bin/g++-14
       run: |
         ./ci/do_ci.sh cmake.maintainer.async.test
     - name: generate test cert
@@ -93,25 +93,25 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_sync_test:
-    name: CMake clang 15 (maintainer mode, sync)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, sync)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, sync)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.sync.test
     - name: generate test cert
@@ -125,25 +125,25 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_async_test:
-    name: CMake clang 15 (maintainer mode, async)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, async)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, async)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.async.test
     - name: generate test cert
@@ -157,25 +157,25 @@ jobs:
         (cd ./functional/otlp; ./run_test.sh)
 
   cmake_clang_maintainer_abiv2_test:
-    name: CMake clang 15 (maintainer mode, abiv2)
-    runs-on: ubuntu-latest
+    name: CMake clang 18 (maintainer mode, abiv2)
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
     - name: setup
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
         PROTOBUF_VERSION: 21.12
       run: |
         sudo -E ./ci/setup_googletest.sh
         sudo -E ./ci/setup_ci_environment.sh
         sudo -E ./ci/install_protobuf.sh
     - name: run cmake clang (maintainer mode, abiv2)
       env:
-        CC: /usr/bin/clang-15
-        CXX: /usr/bin/clang++-15
+        CC: /usr/bin/clang-18
+        CXX: /usr/bin/clang++-18
       run: |
         ./ci/do_ci.sh cmake.maintainer.abiv2.test
     - name: generate test cert

CHANGELOG.md

@@ -15,14 +15,87 @@ Increment the:
 
 ## [Unreleased]
 
-* [EXPORTER] Add OTLP File exporters
-  [#2540](https://github.com/open-telemetry/opentelemetry-cpp/pull/2540)
+* [SDK] Update ExemplarFilter and ExemplarReservoir for spec
+  [#2372](https://github.com/open-telemetry/opentelemetry-cpp/pull/2372)
+
+Notes on experimental features:
+
+* [#2372](https://github.com/open-telemetry/opentelemetry-cpp/issues/2372)
+  introduced `MeterProvider::SetExemplar()` which accepts en
+  `ExemplarFilterType` enumeration with `kAlwaysOff`, `kAlwaysOn` and
+  `kTraceBased`.
+
+## [1.15.0] 2024-04-21
+
+* [EXPORTER] Change OTLP HTTP content_type default to binary
+  [#2564](https://github.com/open-telemetry/opentelemetry-cpp/pull/2564)
+* [DOC] Fix OTLP documentation: Default endpoint is wrong for OTLP/HTTP
+  [#2560](https://github.com/open-telemetry/opentelemetry-cpp/pull/2560)
+* [BUILD] Fix old style cast warning
+  [#2567](https://github.com/open-telemetry/opentelemetry-cpp/pull/2567)
 * [EXPORTER] Gzip compression support for OTLP/HTTP and OTLP/gRPC exporter
   [#2530](https://github.com/open-telemetry/opentelemetry-cpp/pull/2530)
+* [BUILD] update vcpkg submodule to 2024.02.14
+  [#2575](https://github.com/open-telemetry/opentelemetry-cpp/pull/2575)
+* [SDK] Support for OTEL_SERVICE_NAME
+  [#2577](https://github.com/open-telemetry/opentelemetry-cpp/pull/2577)
 * [EXPORTER] Support URL-encoded values for `OTEL_EXPORTER_OTLP_HEADERS`
   [#2579](https://github.com/open-telemetry/opentelemetry-cpp/pull/2579)
+* [BUILD] CMake cleanup for message()
+  [#2582](https://github.com/open-telemetry/opentelemetry-cpp/pull/2582)
+* [BUILD] Bump CMake minimum required version to 3.9
+  [#2581](https://github.com/open-telemetry/opentelemetry-cpp/pull/2581)
+* [BUILD] Provide LIKELY / UNLIKELY macros
+  [#2580](https://github.com/open-telemetry/opentelemetry-cpp/pull/2580)
+* [EXPORTER] OTLP: Fix missing ResourceMetrics SchemaURL
+  [#2587](https://github.com/open-telemetry/opentelemetry-cpp/pull/2587)
+* [ETW] cleanup include path
+  [#2594](https://github.com/open-telemetry/opentelemetry-cpp/pull/2594)
+* Upgrade to googletest 1.14.0
+  [#2596](https://github.com/open-telemetry/opentelemetry-cpp/pull/2596)
+* Upgrade to nlohmann_json 3.11.3
+  [#2595](https://github.com/open-telemetry/opentelemetry-cpp/pull/2595)
+* [BAZEL] Move -std=c++14 to .bazelrc
+  [#2600](https://github.com/open-telemetry/opentelemetry-cpp/pull/2600)
+* [BAZEL] Fix -std=c++14 warning on Windows
+  [#2601](https://github.com/open-telemetry/opentelemetry-cpp/pull/2601)
+* Upgrade to benchmark 1.8.3
+  [#2597](https://github.com/open-telemetry/opentelemetry-cpp/pull/2597)
+* Upgrade to prometheus 1.2.4
+  [#2598](https://github.com/open-telemetry/opentelemetry-cpp/pull/2598)
+* [DOC] Fix typo: Asynchronouse -> Asynchronous in meter.h
+  [#2604](https://github.com/open-telemetry/opentelemetry-cpp/pull/2604)
+* [BUILD] Do not link prometheus-cpp::util when it doesn't exist
+  [#2606](https://github.com/open-telemetry/opentelemetry-cpp/pull/2606)
+* [SDK] Remove unused variable
+  [#2609](https://github.com/open-telemetry/opentelemetry-cpp/pull/2609)
+* [METRICS SDK] Remove extra OfferMeasurement call
+  in SyncMetricsStorage::OfferMeasurement
+  [#2610](https://github.com/open-telemetry/opentelemetry-cpp/pull/2610)
+* [MISC] Use set -e on all shell scripts and pass shellcheck --severity=error
+  [#2616](https://github.com/open-telemetry/opentelemetry-cpp/pull/2616)
+* [CI] Add shellcheck --severity=error as a CI step
+  [#2618](https://github.com/open-telemetry/opentelemetry-cpp/pull/2618)
+* [CI] Upgrade to abseil 20240116.1 (CMake only)
+  [#2599](https://github.com/open-telemetry/opentelemetry-cpp/pull/2599)
+* [CI] Benchmark, provide units with --benchmark_min_time
+  [#2621](https://github.com/open-telemetry/opentelemetry-cpp/pull/2621)
+* [EXPORTER] OTLP file exporter
+  [#2540](https://github.com/open-telemetry/opentelemetry-cpp/pull/2540)
 * [CI] Use platform CMake
   [#2627](https://github.com/open-telemetry/opentelemetry-cpp/pull/2627)
+* [PROTO] Upgrade to opentelemetry-proto 1.2.0
+  [#2631](https://github.com/open-telemetry/opentelemetry-cpp/pull/2631)
+* [SDK] DefaultLogHandler to print errors to std::cerr, add LogLevel::None
+  [#2622](https://github.com/open-telemetry/opentelemetry-cpp/pull/2622)
+* [SEMANTIC CONVENTIONS] Upgrade to semantic convention 1.25.0
+  [#2633](https://github.com/open-telemetry/opentelemetry-cpp/pull/2633)
+* [DOC] Add readme and examples for OTLP FILE exporters.
+  [#2638](https://github.com/open-telemetry/opentelemetry-cpp/pull/2638)
+* [SEMANTIC CONVENTIONS] Rework on semantic conventions 1.25.0
+  [#2640](https://github.com/open-telemetry/opentelemetry-cpp/pull/2640)
+* [DOC] Update INSTALL.md
+  [#2592](https://github.com/open-telemetry/opentelemetry-cpp/pull/2592)
 
 Important changes:
 
@@ -43,6 +116,23 @@ Important changes:
   * As part of this change, the script `ci/setup_cmake.sh` was renamed
     to `ci/setup_googletest.sh`, for clarity, now that this script
     only installs googletest.
+* [SDK] DefaultLogHandler to print to std::cerr, add LogLevel::None
+  [#2622](https://github.com/open-telemetry/opentelemetry-cpp/pull/2622)
+  * Change DefaultLogHandler output
+    * Before, the default internal logger, DefaultLogHandler,
+      used to print to std::cout.
+    * Now, DefaultLogHandler prints errors and warnings to std::cerr,
+      as expected, while printing info and debug messages to std::cout.
+    * Applications that expected to find the opentelemetry-cpp internal
+      error log in std::cout may need adjustments, either by looking
+      at std::cerr instead, or by using a custom log handler.
+  * Additional LogLevel::None
+    * LogLevel::None is a new supported log level, which does not print
+      any message.
+    * Custom log handlers may need to implement a new case, to avoid
+      compiler warnings.
+    * Numbering of log levels like OTEL_INTERNAL_LOG_LEVEL_ERROR
+      has changed, which requires to rebuild, as the SDK ABI differs.
 
 ## [1.14.2] 2024-02-27
 

INSTALL.md

@@ -85,6 +85,8 @@ You can link OpenTelemetry C++ SDK with libraries provided in
    - `-DWITH_OTLP_GRPC=ON` : To enable building OTLP GRPC exporter.
    - `-DWITH_OTLP_HTTP=ON` : To enable building OTLP HTTP exporter.
    - `-DWITH_PROMETHEUS=ON` : To enable building prometheus exporter.
+   - `-DOPENTELEMETRY_INSTALL=ON`: To install `otel-cpp` library needed
+      for external code linking.
 
 3. Once the build configuration is created, build the CMake targets - this
    includes building SDKs and unittests for API and SDK. Note that since API is

api/CMakeLists.txt

@@ -131,6 +131,10 @@ if(WITH_OTLP_HTTP_COMPRESSION)
                              INTERFACE ENABLE_OTLP_COMPRESSION_PREVIEW)
 endif()
 
+if(APPLE)
+  target_link_libraries(opentelemetry_api INTERFACE "-framework CoreFoundation")
+endif()
+
 include(${PROJECT_SOURCE_DIR}/cmake/pkgconfig.cmake)
 
 if(OPENTELEMETRY_INSTALL)

api/include/opentelemetry/logs/event_logger.h

@@ -64,10 +64,6 @@ class EventLogger
       return;
     }
     nostd::unique_ptr<LogRecord> log_record = delegate_logger->CreateLogRecord();
-    if (!log_record)
-    {
-      return;
-    }
 
     IgnoreTraitResult(
         detail::LogRecordSetterTrait<typename std::decay<ArgumentType>::type>::template Set(

api/include/opentelemetry/logs/logger.h

@@ -100,10 +100,6 @@ class Logger
   void EmitLogRecord(ArgumentType &&... args)
   {
     nostd::unique_ptr<LogRecord> log_record = CreateLogRecord();
-    if (!log_record)
-    {
-      return;
-    }
 
     EmitLogRecord(std::move(log_record), std::forward<ArgumentType>(args)...);
   }

api/include/opentelemetry/logs/noop.h

@@ -34,11 +34,39 @@ class NoopLogger final : public Logger
 public:
   const nostd::string_view GetName() noexcept override { return "noop logger"; }
 
-  nostd::unique_ptr<LogRecord> CreateLogRecord() noexcept override { return nullptr; }
+  nostd::unique_ptr<LogRecord> CreateLogRecord() noexcept override
+  {
+    /*
+     * Do not return memory shared between threads,
+     * a `new` + `delete` for each noop record can not be avoided,
+     * due to the semantic of unique_ptr.
+     */
+    return nostd::unique_ptr<LogRecord>(new NoopLogRecord());
+  }
 
   using Logger::EmitLogRecord;
 
   void EmitLogRecord(nostd::unique_ptr<LogRecord> &&) noexcept override {}
+
+private:
+  class NoopLogRecord : public LogRecord
+  {
+  public:
+    NoopLogRecord()           = default;
+    ~NoopLogRecord() override = default;
+
+    void SetTimestamp(common::SystemTimestamp /* timestamp */) noexcept override {}
+    void SetObservedTimestamp(common::SystemTimestamp /* timestamp */) noexcept override {}
+    void SetSeverity(logs::Severity /* severity */) noexcept override {}
+    void SetBody(const common::AttributeValue & /* message */) noexcept override {}
+    void SetAttribute(nostd::string_view /* key */,
+                      const common::AttributeValue & /* value */) noexcept override
+    {}
+    void SetEventId(int64_t /* id */, nostd::string_view /* name */) noexcept override {}
+    void SetTraceId(const trace::TraceId & /* trace_id */) noexcept override {}
+    void SetSpanId(const trace::SpanId & /* span_id */) noexcept override {}
+    void SetTraceFlags(const trace::TraceFlags & /* trace_flags */) noexcept override {}
+  };
 };
 
 /**