From 7095cf3802b2854d7a9e90fd3aa4e1a13f4f6d81 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Tue, 27 Jun 2023 23:03:32 +0200
Subject: [PATCH 1/8] Fixes #2184

---
 CMakeLists.txt                                | 57 +++++++++++++++++--
 api/CMakeLists.txt                            |  4 ++
 .../opentelemetry/metrics/meter_provider.h    |  6 ++
 api/include/opentelemetry/metrics/noop.h      |  7 +++
 api/include/opentelemetry/version.h           |  5 +-
 .../otlp_grpc_log_record_exporter_test.cc     |  6 +-
 .../opentelemetry/sdk/metrics/meter_context.h |  4 ++
 .../sdk/metrics/meter_provider.h              | 11 ++++
 sdk/src/metrics/meter_context.cc              | 21 +++++++
 sdk/src/metrics/meter_provider.cc             | 15 +++++
 sdk/test/logs/log_record_test.cc              |  4 +-
 11 files changed, 128 insertions(+), 12 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37e0be94a6..cdf774694d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -89,17 +89,46 @@ if(VCPKG_CHAINLOAD_TOOLCHAIN_FILE)
   include("${VCPKG_CHAINLOAD_TOOLCHAIN_FILE}")
 endif()
 
+#
+# ABI VERSION 1 is frozen, and can not change.
+#
+# For fixes or features that causes an API/ABI breaking change,
+# the change is implemented in ABI VERSION 2.
+#
+# ABI VERSION 2 is still experimental, unstable,
+# and will by definition change when more breaking changes
+# are implemented.
+#
+# When version 2 is sufficiently mature and contains a coherent
+# set of new features, it will be marked stable and published.
+#
+# The goal is to avoid incrementing the ABI version on individual fixes,
+# and release a stable set less frequently, to minimize disruption to users.
+#
+# Until ABI_VERSION_2 is marked stable, use WITH_ABI_VERSION_2_PREVIEW=ON
+# at your own risk, as there are no compatibility guarantees.
+#
+option(WITH_ABI_VERSION_2_PREVIEW "EXPERIMENTAL: ABI version 2 preview" OFF)
+
 file(READ "${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
      OPENTELEMETRY_CPP_HEADER_VERSION_H)
-if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
-   "OPENTELEMETRY_ABI_VERSION_NO[ \t\r\n]+\"?([0-9]+)\"?")
-  math(EXPR OPENTELEMETRY_ABI_VERSION_NO ${CMAKE_MATCH_1})
+
+if (WITH_ABI_VERSION_2_PREVIEW)
+  set(OPENTELEMETRY_ABI_VERSION_NO "2")
 else()
-  message(
-    FATAL_ERROR
+  if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
+     "OPENTELEMETRY_ABI_VERSION_NO[ \t\r\n]+\"?([0-9]+)\"?")
+    math(EXPR OPENTELEMETRY_ABI_VERSION_NO ${CMAKE_MATCH_1})
+  else()
+    message(
+      FATAL_ERROR
       "OPENTELEMETRY_ABI_VERSION_NO not found on ${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
-  )
+    )
+  endif()
 endif()
+
+message(STATUS "OPENTELEMETRY_ABI_VERSION_NO=${OPENTELEMETRY_ABI_VERSION_NO}")
+
 if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
    "OPENTELEMETRY_VERSION[ \t\r\n]+\"?([^\"]+)\"?")
   set(OPENTELEMETRY_VERSION ${CMAKE_MATCH_1})
@@ -110,6 +139,8 @@ else()
   )
 endif()
 
+message(STATUS "OPENTELEMETRY_VERSION=${OPENTELEMETRY_VERSION}")
+
 option(WITH_NO_DEPRECATED_CODE "Do not include deprecated code" OFF)
 
 option(WITH_STL "Whether to use Standard Library for C++ latest features" OFF)
@@ -265,6 +296,20 @@ if(WITH_OTLP_HTTP_SSL_TLS_PREVIEW AND NOT WITH_OTLP_HTTP_SSL_PREVIEW)
   )
 endif()
 
+#
+# ABI_VERSION_2 is not stable, do not build shared libraries with it.
+#
+if(OTELCPP_VERSIONED_LIBS AND WITH_ABI_VERSION_2_PREVIEW)
+  message(FATAL_ERROR "OTELCPP_VERSIONED_LIBS=ON requires WITH_ABI_VERSION_2_PREVIEW=OFF")
+endif()
+
+#
+# ABI_VERSION_2 is not stable, do not build DLL with it.
+#
+if(DEFINED OPENTELEMETRY_BUILD_DLL AND WITH_ABI_VERSION_2_PREVIEW)
+  message(FATAL_ERROR "OPENTELEMETRY_BUILD_DLL requires WITH_ABI_VERSION_2_PREVIEW=OFF")
+endif()
+
 find_package(Threads)
 
 function(install_windows_deps)
diff --git a/api/CMakeLists.txt b/api/CMakeLists.txt
index 31863b25e3..591af2bbee 100644
--- a/api/CMakeLists.txt
+++ b/api/CMakeLists.txt
@@ -98,6 +98,10 @@ if(WITH_ASYNC_EXPORT_PREVIEW)
   target_compile_definitions(opentelemetry_api INTERFACE ENABLE_ASYNC_EXPORT)
 endif()
 
+if(WITH_ABI_VERSION_2_PREVIEW)
+  target_compile_definitions(opentelemetry_api INTERFACE OPENTELEMETRY_ABI_VERSION_NO=2)
+endif()
+
 # A better place should be in sdk, not api
 if(WITH_OTLP_HTTP_SSL_PREVIEW)
   target_compile_definitions(opentelemetry_api
diff --git a/api/include/opentelemetry/metrics/meter_provider.h b/api/include/opentelemetry/metrics/meter_provider.h
index 654c4022ea..b24263be71 100644
--- a/api/include/opentelemetry/metrics/meter_provider.h
+++ b/api/include/opentelemetry/metrics/meter_provider.h
@@ -29,6 +29,12 @@ class MeterProvider
   virtual nostd::shared_ptr<Meter> GetMeter(nostd::string_view library_name,
                                             nostd::string_view library_version = "",
                                             nostd::string_view schema_url      = "") noexcept = 0;
+
+#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+  virtual void RemoveMeter(nostd::string_view library_name,
+                           nostd::string_view library_version = "",
+                           nostd::string_view schema_url      = "") noexcept = 0;
+#endif
 };
 }  // namespace metrics
 OPENTELEMETRY_END_NAMESPACE
diff --git a/api/include/opentelemetry/metrics/noop.h b/api/include/opentelemetry/metrics/noop.h
index 3a754a6e00..0e373f24a1 100644
--- a/api/include/opentelemetry/metrics/noop.h
+++ b/api/include/opentelemetry/metrics/noop.h
@@ -203,6 +203,13 @@ class NoopMeterProvider final : public MeterProvider
     return meter_;
   }
 
+#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+  void RemoveMeter(nostd::string_view /* name */,
+                   nostd::string_view /* version */,
+                   nostd::string_view /* schema_url */) noexcept override
+  {}
+#endif
+
 private:
   nostd::shared_ptr<Meter> meter_;
 };
diff --git a/api/include/opentelemetry/version.h b/api/include/opentelemetry/version.h
index 2178591728..0ff8d71d32 100644
--- a/api/include/opentelemetry/version.h
+++ b/api/include/opentelemetry/version.h
@@ -6,7 +6,10 @@
 #include "opentelemetry/common/macros.h"
 #include "opentelemetry/detail/preprocessor.h"
 
-#define OPENTELEMETRY_ABI_VERSION_NO 1
+#ifndef OPENTELEMETRY_ABI_VERSION_NO
+#  define OPENTELEMETRY_ABI_VERSION_NO 1
+#endif
+
 #define OPENTELEMETRY_VERSION "1.9.1"
 #define OPENTELEMETRY_VERSION_MAJOR 1
 #define OPENTELEMETRY_VERSION_MINOR 9
diff --git a/exporters/otlp/test/otlp_grpc_log_record_exporter_test.cc b/exporters/otlp/test/otlp_grpc_log_record_exporter_test.cc
index f2ed416327..518caaba5e 100644
--- a/exporters/otlp/test/otlp_grpc_log_record_exporter_test.cc
+++ b/exporters/otlp/test/otlp_grpc_log_record_exporter_test.cc
@@ -154,7 +154,7 @@ TEST_F(OtlpGrpcLogRecordExporterTestPeer, ExportIntegrationTest)
   std::unique_ptr<proto::collector::trace::v1::TraceService::StubInterface> trace_stub_interface(
       trace_mock_stub);
 
-  auto trace_provider = opentelemetry::nostd::shared_ptr<opentelemetry::v1::trace::TracerProvider>(
+  auto trace_provider = opentelemetry::nostd::shared_ptr<opentelemetry::trace::TracerProvider>(
       opentelemetry::sdk::trace::TracerProviderFactory::Create(
           opentelemetry::sdk::trace::SimpleSpanProcessorFactory::Create(
               GetExporter(trace_stub_interface))));
@@ -174,7 +174,7 @@ TEST_F(OtlpGrpcLogRecordExporterTestPeer, ExportIntegrationTest)
 
     auto logger = provider->GetLogger("test", "opentelelemtry_library", "", schema_url,
                                       {{"scope_key1", "scope_value"}, {"scope_key2", 2}});
-    std::unordered_map<std::string, opentelemetry::v1::common::AttributeValue> attributes;
+    std::unordered_map<std::string, opentelemetry::common::AttributeValue> attributes;
     attributes["service.name"]     = "unit_test_service";
     attributes["tenant.id"]        = "test_user";
     attributes["bool_value"]       = true;
@@ -197,7 +197,7 @@ TEST_F(OtlpGrpcLogRecordExporterTestPeer, ExportIntegrationTest)
   opentelemetry::trace::Provider::SetTracerProvider(
       opentelemetry::nostd::shared_ptr<opentelemetry::trace::TracerProvider>(
           new opentelemetry::trace::NoopTracerProvider()));
-  trace_provider = opentelemetry::nostd::shared_ptr<opentelemetry::v1::trace::TracerProvider>();
+  trace_provider = opentelemetry::nostd::shared_ptr<opentelemetry::trace::TracerProvider>();
 }
 
 }  // namespace otlp
diff --git a/sdk/include/opentelemetry/sdk/metrics/meter_context.h b/sdk/include/opentelemetry/sdk/metrics/meter_context.h
index 8155b4da9f..336f5da7a0 100644
--- a/sdk/include/opentelemetry/sdk/metrics/meter_context.h
+++ b/sdk/include/opentelemetry/sdk/metrics/meter_context.h
@@ -115,6 +115,10 @@ class MeterContext : public std::enable_shared_from_this<MeterContext>
    */
   void AddMeter(std::shared_ptr<Meter> meter);
 
+  void RemoveMeter(nostd::string_view name,
+                   nostd::string_view version,
+                   nostd::string_view schema_url);
+
   /**
    * Force all active Collectors to flush any buffered meter data
    * within the given timeout.
diff --git a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
index fedf6aac61..bf21d3c1da 100644
--- a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
+++ b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
@@ -53,6 +53,17 @@ class MeterProvider final : public opentelemetry::metrics::MeterProvider
       nostd::string_view version    = "",
       nostd::string_view schema_url = "") noexcept override;
 
+#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+  void RemoveMeter(nostd::string_view name,
+                   nostd::string_view version,
+                   nostd::string_view schema_url) noexcept override;
+#else
+  /* Only in the SDK, not API, for ABI VERSION 1 */
+  void RemoveMeter(nostd::string_view name,
+                   nostd::string_view version,
+                   nostd::string_view schema_url) noexcept;
+#endif
+
   /**
    * Obtain the resource associated with this meter provider.
    * @return The resource for this meter provider.
diff --git a/sdk/src/metrics/meter_context.cc b/sdk/src/metrics/meter_context.cc
index eaf82232d6..c6526192ef 100644
--- a/sdk/src/metrics/meter_context.cc
+++ b/sdk/src/metrics/meter_context.cc
@@ -3,6 +3,7 @@
 
 #include "opentelemetry/sdk/metrics/meter_context.h"
 #include "opentelemetry/sdk/common/global_log_handler.h"
+#include "opentelemetry/sdk/metrics/meter.h"
 #include "opentelemetry/sdk/metrics/metric_reader.h"
 #include "opentelemetry/sdk/metrics/state/metric_collector.h"
 #include "opentelemetry/sdk_config.h"
@@ -79,6 +80,26 @@ void MeterContext::AddMeter(std::shared_ptr<Meter> meter)
   meters_.push_back(meter);
 }
 
+void MeterContext::RemoveMeter(nostd::string_view name,
+                               nostd::string_view version,
+                               nostd::string_view schema_url)
+{
+  std::lock_guard<opentelemetry::common::SpinLockMutex> guard(meter_lock_);
+
+  std::vector<std::shared_ptr<Meter>> filtered_meters;
+
+  for (auto &meter : meters_)
+  {
+    auto scope = meter->GetInstrumentationScope();
+    if (!scope->equal(name, version, schema_url))
+    {
+      filtered_meters.push_back(meter);
+    }
+  }
+
+  meters_.swap(filtered_meters);
+}
+
 bool MeterContext::Shutdown() noexcept
 {
   bool result = true;
diff --git a/sdk/src/metrics/meter_provider.cc b/sdk/src/metrics/meter_provider.cc
index 1e9dc5f434..b8720ded15 100644
--- a/sdk/src/metrics/meter_provider.cc
+++ b/sdk/src/metrics/meter_provider.cc
@@ -57,6 +57,21 @@ nostd::shared_ptr<metrics_api::Meter> MeterProvider::GetMeter(
   return nostd::shared_ptr<metrics_api::Meter>{meter};
 }
 
+void MeterProvider::RemoveMeter(nostd::string_view name,
+                                nostd::string_view version,
+                                nostd::string_view schema_url) noexcept
+{
+  if (name.data() == nullptr || name == "")
+  {
+    OTEL_INTERNAL_LOG_WARN("[MeterProvider::RemoveMeter] Library name is empty.");
+    name = "";
+  }
+
+  const std::lock_guard<std::mutex> guard(lock_);
+
+  context_->RemoveMeter(name, version, schema_url);
+}
+
 const resource::Resource &MeterProvider::GetResource() const noexcept
 {
   return context_->GetResource();
diff --git a/sdk/test/logs/log_record_test.cc b/sdk/test/logs/log_record_test.cc
index 0e5de03050..4f7deb06d0 100644
--- a/sdk/test/logs/log_record_test.cc
+++ b/sdk/test/logs/log_record_test.cc
@@ -99,13 +99,13 @@ class TestBodyLogger : public opentelemetry::logs::Logger
     }
   }
 
-  const opentelemetry::v1::common::AttributeValue &GetLastLogRecord() const noexcept
+  const opentelemetry::common::AttributeValue &GetLastLogRecord() const noexcept
   {
     return last_body_;
   }
 
 private:
-  opentelemetry::v1::common::AttributeValue last_body_;
+  opentelemetry::common::AttributeValue last_body_;
 };
 
 // Define a basic LoggerProvider class that returns an instance of the logger class defined above

From 556da00d65547dad1dd10310846c501e68cbc24c Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Fri, 30 Jun 2023 10:49:47 +0200
Subject: [PATCH 2/8] Format, CI

---
 .github/workflows/ci.yml | 33 +++++++++++++++++++++++++++++++++
 CMakeLists.txt           | 33 ++++++++++++++++++---------------
 api/CMakeLists.txt       |  3 ++-
 ci/do_ci.sh              | 23 +++++++++++++++++++++++
 4 files changed, 76 insertions(+), 16 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8ac8999459..dcff500ca2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -202,6 +202,39 @@ jobs:
       run: |
         (cd ./functional/otlp; ./run_test.sh)
 
+  cmake_clang_maintainer_abi_v2_test:
+    name: CMake clang 14 (maintainer mode, abi v2)
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        submodules: 'recursive'
+    - name: setup
+      env:
+        CC: /usr/bin/clang-14
+        CXX: /usr/bin/clang++-14
+        GOOGLETEST_VERSION: 1.12.1
+        PROTOBUF_VERSION: 21.12
+      run: |
+        sudo -E ./ci/setup_cmake.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-14
+        CXX: /usr/bin/clang++-14
+      run: |
+        ./ci/do_ci.sh cmake.maintainer.abiv2.test
+    - name: generate test cert
+      env:
+        CFSSL_VERSION: 1.6.3
+      run: |
+        sudo -E ./tools/setup-cfssl.sh
+        (cd ./functional/cert; ./generate_cert.sh)
+    - name: run func test
+      run: |
+        (cd ./functional/otlp; ./run_test.sh)
+
   cmake_msvc_maintainer_test:
     name: CMake msvc (maintainer mode)
     runs-on: windows-latest
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 33acd0695f..b9a2a5bc52 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -92,28 +92,27 @@ endif()
 #
 # ABI VERSION 1 is frozen, and can not change.
 #
-# For fixes or features that causes an API/ABI breaking change,
-# the change is implemented in ABI VERSION 2.
+# For fixes or features that causes an API/ABI breaking change, the change is
+# implemented in ABI VERSION 2.
 #
-# ABI VERSION 2 is still experimental, unstable,
-# and will by definition change when more breaking changes
-# are implemented.
+# ABI VERSION 2 is still experimental, unstable, and will by definition change
+# when more breaking changes are implemented.
 #
-# When version 2 is sufficiently mature and contains a coherent
-# set of new features, it will be marked stable and published.
+# When version 2 is sufficiently mature and contains a coherent set of new
+# features, it will be marked stable and published.
 #
-# The goal is to avoid incrementing the ABI version on individual fixes,
-# and release a stable set less frequently, to minimize disruption to users.
+# The goal is to avoid incrementing the ABI version on individual fixes, and
+# release a stable set less frequently, to minimize disruption to users.
 #
-# Until ABI_VERSION_2 is marked stable, use WITH_ABI_VERSION_2_PREVIEW=ON
-# at your own risk, as there are no compatibility guarantees.
+# Until ABI_VERSION_2 is marked stable, use WITH_ABI_VERSION_2_PREVIEW=ON at
+# your own risk, as there are no compatibility guarantees.
 #
 option(WITH_ABI_VERSION_2_PREVIEW "EXPERIMENTAL: ABI version 2 preview" OFF)
 
 file(READ "${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
      OPENTELEMETRY_CPP_HEADER_VERSION_H)
 
-if (WITH_ABI_VERSION_2_PREVIEW)
+if(WITH_ABI_VERSION_2_PREVIEW)
   set(OPENTELEMETRY_ABI_VERSION_NO "2")
 else()
   if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
@@ -122,7 +121,7 @@ else()
   else()
     message(
       FATAL_ERROR
-      "OPENTELEMETRY_ABI_VERSION_NO not found on ${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
+        "OPENTELEMETRY_ABI_VERSION_NO not found on ${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
     )
   endif()
 endif()
@@ -300,14 +299,18 @@ endif()
 # ABI_VERSION_2 is not stable, do not build shared libraries with it.
 #
 if(OTELCPP_VERSIONED_LIBS AND WITH_ABI_VERSION_2_PREVIEW)
-  message(FATAL_ERROR "OTELCPP_VERSIONED_LIBS=ON requires WITH_ABI_VERSION_2_PREVIEW=OFF")
+  message(
+    FATAL_ERROR
+      "OTELCPP_VERSIONED_LIBS=ON requires WITH_ABI_VERSION_2_PREVIEW=OFF")
 endif()
 
 #
 # ABI_VERSION_2 is not stable, do not build DLL with it.
 #
 if(DEFINED OPENTELEMETRY_BUILD_DLL AND WITH_ABI_VERSION_2_PREVIEW)
-  message(FATAL_ERROR "OPENTELEMETRY_BUILD_DLL requires WITH_ABI_VERSION_2_PREVIEW=OFF")
+  message(
+    FATAL_ERROR
+      "OPENTELEMETRY_BUILD_DLL requires WITH_ABI_VERSION_2_PREVIEW=OFF")
 endif()
 
 find_package(Threads)
diff --git a/api/CMakeLists.txt b/api/CMakeLists.txt
index 591af2bbee..b0dedc6232 100644
--- a/api/CMakeLists.txt
+++ b/api/CMakeLists.txt
@@ -99,7 +99,8 @@ if(WITH_ASYNC_EXPORT_PREVIEW)
 endif()
 
 if(WITH_ABI_VERSION_2_PREVIEW)
-  target_compile_definitions(opentelemetry_api INTERFACE OPENTELEMETRY_ABI_VERSION_NO=2)
+  target_compile_definitions(opentelemetry_api
+                             INTERFACE OPENTELEMETRY_ABI_VERSION_NO=2)
 endif()
 
 # A better place should be in sdk, not api
diff --git a/ci/do_ci.sh b/ci/do_ci.sh
index d504b33ae8..7e23a4e1aa 100755
--- a/ci/do_ci.sh
+++ b/ci/do_ci.sh
@@ -136,6 +136,29 @@ elif [[ "$1" == "cmake.maintainer.async.test" ]]; then
   make -k -j $(nproc)
   make test
   exit 0
+elif [[ "$1" == "cmake.maintainer.abiv2.test" ]]; then
+  cd "${BUILD_DIR}"
+  rm -rf *
+  cmake -DCMAKE_BUILD_TYPE=Debug  \
+        -DWITH_OTLP_HTTP=ON \
+        -DWITH_OTLP_HTTP_SSL_PREVIEW=ON \
+        -DWITH_OTLP_HTTP_SSL_TLS_PREVIEW=ON \
+        -DWITH_PROMETHEUS=ON \
+        -DWITH_EXAMPLES=ON \
+        -DWITH_EXAMPLES_HTTP=ON \
+        -DWITH_ZIPKIN=ON \
+        -DBUILD_W3CTRACECONTEXT_TEST=ON \
+        -DWITH_ELASTICSEARCH=ON \
+        -DWITH_LOGS_PREVIEW=ON \
+        -DWITH_METRICS_EXEMPLAR_PREVIEW=ON \
+        -DWITH_ASYNC_EXPORT_PREVIEW=OFF \
+        -DOTELCPP_MAINTAINER_MODE=ON \
+        -DWITH_NO_DEPRECATED_CODE=ON \
+        -DWITH_ABI_VERSION_2_PREVIEW=ON \
+        "${SRC_DIR}"
+  make -k
+  make test
+  exit 0
 elif [[ "$1" == "cmake.maintainer.cpp11.async.test" ]]; then
   cd "${BUILD_DIR}"
   rm -rf *

From febe93f25d27e748b61cdde4d9c32943711f5258 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 3 Jul 2023 14:32:06 +0200
Subject: [PATCH 3/8] Cleanup

---
 .github/workflows/ci.yml                      | 33 ----------
 CMakeLists.txt                                | 64 +++----------------
 api/CMakeLists.txt                            |  4 +-
 .../opentelemetry/metrics/meter_provider.h    |  3 +-
 api/include/opentelemetry/metrics/noop.h      |  2 +-
 ci/do_ci.sh                                   | 23 -------
 6 files changed, 13 insertions(+), 116 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2941d61850..e1666dabbb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -197,39 +197,6 @@ jobs:
       run: |
         (cd ./functional/otlp; ./run_test.sh)
 
-  cmake_clang_maintainer_abi_v2_test:
-    name: CMake clang 14 (maintainer mode, abi v2)
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v3
-      with:
-        submodules: 'recursive'
-    - name: setup
-      env:
-        CC: /usr/bin/clang-14
-        CXX: /usr/bin/clang++-14
-        GOOGLETEST_VERSION: 1.12.1
-        PROTOBUF_VERSION: 21.12
-      run: |
-        sudo -E ./ci/setup_cmake.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-14
-        CXX: /usr/bin/clang++-14
-      run: |
-        ./ci/do_ci.sh cmake.maintainer.abiv2.test
-    - name: generate test cert
-      env:
-        CFSSL_VERSION: 1.6.3
-      run: |
-        sudo -E ./tools/setup-cfssl.sh
-        (cd ./functional/cert; ./generate_cert.sh)
-    - name: run func test
-      run: |
-        (cd ./functional/otlp; ./run_test.sh)
-
   cmake_msvc_maintainer_test:
     name: CMake msvc (maintainer mode)
     runs-on: windows-latest
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c81c693741..2ab09fc0dc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -89,45 +89,17 @@ if(VCPKG_CHAINLOAD_TOOLCHAIN_FILE)
   include("${VCPKG_CHAINLOAD_TOOLCHAIN_FILE}")
 endif()
 
-#
-# ABI VERSION 1 is frozen, and can not change.
-#
-# For fixes or features that causes an API/ABI breaking change, the change is
-# implemented in ABI VERSION 2.
-#
-# ABI VERSION 2 is still experimental, unstable, and will by definition change
-# when more breaking changes are implemented.
-#
-# When version 2 is sufficiently mature and contains a coherent set of new
-# features, it will be marked stable and published.
-#
-# The goal is to avoid incrementing the ABI version on individual fixes, and
-# release a stable set less frequently, to minimize disruption to users.
-#
-# Until ABI_VERSION_2 is marked stable, use WITH_ABI_VERSION_2_PREVIEW=ON at
-# your own risk, as there are no compatibility guarantees.
-#
-option(WITH_ABI_VERSION_2_PREVIEW "EXPERIMENTAL: ABI version 2 preview" OFF)
-
 file(READ "${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
      OPENTELEMETRY_CPP_HEADER_VERSION_H)
-
-if(WITH_ABI_VERSION_2_PREVIEW)
-  set(OPENTELEMETRY_ABI_VERSION_NO "2")
+if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
+   "OPENTELEMETRY_ABI_VERSION_NO[ \t\r\n]+\"?([0-9]+)\"?")
+  math(EXPR OPENTELEMETRY_ABI_VERSION_NO ${CMAKE_MATCH_1})
 else()
-  if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
-     "OPENTELEMETRY_ABI_VERSION_NO[ \t\r\n]+\"?([0-9]+)\"?")
-    math(EXPR OPENTELEMETRY_ABI_VERSION_NO ${CMAKE_MATCH_1})
-  else()
-    message(
-      FATAL_ERROR
-        "OPENTELEMETRY_ABI_VERSION_NO not found on ${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
-    )
-  endif()
+  message(
+    FATAL_ERROR
+      "OPENTELEMETRY_ABI_VERSION_NO not found on ${CMAKE_CURRENT_LIST_DIR}/api/include/opentelemetry/version.h"
+  )
 endif()
-
-message(STATUS "OPENTELEMETRY_ABI_VERSION_NO=${OPENTELEMETRY_ABI_VERSION_NO}")
-
 if(OPENTELEMETRY_CPP_HEADER_VERSION_H MATCHES
    "OPENTELEMETRY_VERSION[ \t\r\n]+\"?([^\"]+)\"?")
   set(OPENTELEMETRY_VERSION ${CMAKE_MATCH_1})
@@ -138,8 +110,6 @@ else()
   )
 endif()
 
-message(STATUS "OPENTELEMETRY_VERSION=${OPENTELEMETRY_VERSION}")
-
 option(WITH_NO_DEPRECATED_CODE "Do not include deprecated code" OFF)
 
 option(WITH_STL "Whether to use Standard Library for C++ latest features" OFF)
@@ -227,6 +197,8 @@ option(WITH_OPENTRACING "Whether to include the Opentracing shim" OFF)
 option(OTELCPP_VERSIONED_LIBS "Whether to generate the versioned shared libs"
        OFF)
 
+option(WITH_REMOVE_METERS_PREVIEW "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)
+
 if(OTELCPP_VERSIONED_LIBS AND NOT BUILD_SHARED_LIBS)
   message(FATAL_ERROR "OTELCPP_VERSIONED_LIBS=ON requires BUILD_SHARED_LIBS=ON")
 endif()
@@ -293,24 +265,6 @@ if(WITH_OTLP_HTTP_SSL_TLS_PREVIEW AND NOT WITH_OTLP_HTTP_SSL_PREVIEW)
   )
 endif()
 
-#
-# ABI_VERSION_2 is not stable, do not build shared libraries with it.
-#
-if(OTELCPP_VERSIONED_LIBS AND WITH_ABI_VERSION_2_PREVIEW)
-  message(
-    FATAL_ERROR
-      "OTELCPP_VERSIONED_LIBS=ON requires WITH_ABI_VERSION_2_PREVIEW=OFF")
-endif()
-
-#
-# ABI_VERSION_2 is not stable, do not build DLL with it.
-#
-if(DEFINED OPENTELEMETRY_BUILD_DLL AND WITH_ABI_VERSION_2_PREVIEW)
-  message(
-    FATAL_ERROR
-      "OPENTELEMETRY_BUILD_DLL requires WITH_ABI_VERSION_2_PREVIEW=OFF")
-endif()
-
 find_package(Threads)
 
 function(install_windows_deps)
diff --git a/api/CMakeLists.txt b/api/CMakeLists.txt
index 3a6b908f81..88e0da46fa 100644
--- a/api/CMakeLists.txt
+++ b/api/CMakeLists.txt
@@ -98,9 +98,9 @@ if(WITH_ASYNC_EXPORT_PREVIEW)
   target_compile_definitions(opentelemetry_api INTERFACE ENABLE_ASYNC_EXPORT)
 endif()
 
-if(WITH_ABI_VERSION_2_PREVIEW)
+if(WITH_REMOVE_METERS_PREVIEW)
   target_compile_definitions(opentelemetry_api
-                             INTERFACE OPENTELEMETRY_ABI_VERSION_NO=2)
+                             INTERFACE ENABLE_REMOVE_METERS_PREVIEW)
 endif()
 
 # A better place should be in sdk, not api
diff --git a/api/include/opentelemetry/metrics/meter_provider.h b/api/include/opentelemetry/metrics/meter_provider.h
index b24263be71..e1015cb2e3 100644
--- a/api/include/opentelemetry/metrics/meter_provider.h
+++ b/api/include/opentelemetry/metrics/meter_provider.h
@@ -29,8 +29,7 @@ class MeterProvider
   virtual nostd::shared_ptr<Meter> GetMeter(nostd::string_view library_name,
                                             nostd::string_view library_version = "",
                                             nostd::string_view schema_url      = "") noexcept = 0;
-
-#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+#ifdef ENABLE_REMOVE_METERS_PREVIEW
   virtual void RemoveMeter(nostd::string_view library_name,
                            nostd::string_view library_version = "",
                            nostd::string_view schema_url      = "") noexcept = 0;
diff --git a/api/include/opentelemetry/metrics/noop.h b/api/include/opentelemetry/metrics/noop.h
index 0e373f24a1..a4b3e10ae9 100644
--- a/api/include/opentelemetry/metrics/noop.h
+++ b/api/include/opentelemetry/metrics/noop.h
@@ -203,7 +203,7 @@ class NoopMeterProvider final : public MeterProvider
     return meter_;
   }
 
-#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+#ifdef ENABLE_REMOVE_METERS_PREVIEW
   void RemoveMeter(nostd::string_view /* name */,
                    nostd::string_view /* version */,
                    nostd::string_view /* schema_url */) noexcept override
diff --git a/ci/do_ci.sh b/ci/do_ci.sh
index 170c4bb493..e4e4807c82 100755
--- a/ci/do_ci.sh
+++ b/ci/do_ci.sh
@@ -133,29 +133,6 @@ elif [[ "$1" == "cmake.maintainer.async.test" ]]; then
   make -k -j $(nproc)
   make test
   exit 0
-elif [[ "$1" == "cmake.maintainer.abiv2.test" ]]; then
-  cd "${BUILD_DIR}"
-  rm -rf *
-  cmake -DCMAKE_BUILD_TYPE=Debug  \
-        -DWITH_OTLP_HTTP=ON \
-        -DWITH_OTLP_HTTP_SSL_PREVIEW=ON \
-        -DWITH_OTLP_HTTP_SSL_TLS_PREVIEW=ON \
-        -DWITH_PROMETHEUS=ON \
-        -DWITH_EXAMPLES=ON \
-        -DWITH_EXAMPLES_HTTP=ON \
-        -DWITH_ZIPKIN=ON \
-        -DBUILD_W3CTRACECONTEXT_TEST=ON \
-        -DWITH_ELASTICSEARCH=ON \
-        -DWITH_LOGS_PREVIEW=ON \
-        -DWITH_METRICS_EXEMPLAR_PREVIEW=ON \
-        -DWITH_ASYNC_EXPORT_PREVIEW=OFF \
-        -DOTELCPP_MAINTAINER_MODE=ON \
-        -DWITH_NO_DEPRECATED_CODE=ON \
-        -DWITH_ABI_VERSION_2_PREVIEW=ON \
-        "${SRC_DIR}"
-  make -k
-  make test
-  exit 0
 elif [[ "$1" == "cmake.maintainer.cpp11.async.test" ]]; then
   cd "${BUILD_DIR}"
   rm -rf *

From e1d8c5b86fbf024cb071d907bc019f75009cfc2f Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 3 Jul 2023 14:41:32 +0200
Subject: [PATCH 4/8] Cleanup

---
 CMakeLists.txt                                         | 3 ++-
 api/include/opentelemetry/version.h                    | 5 +----
 sdk/include/opentelemetry/sdk/metrics/meter_provider.h | 7 +------
 sdk/src/metrics/meter_provider.cc                      | 2 ++
 4 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2ab09fc0dc..698489a3f1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -197,7 +197,8 @@ option(WITH_OPENTRACING "Whether to include the Opentracing shim" OFF)
 option(OTELCPP_VERSIONED_LIBS "Whether to generate the versioned shared libs"
        OFF)
 
-option(WITH_REMOVE_METERS_PREVIEW "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)
+option(WITH_REMOVE_METERS_PREVIEW
+       "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)
 
 if(OTELCPP_VERSIONED_LIBS AND NOT BUILD_SHARED_LIBS)
   message(FATAL_ERROR "OTELCPP_VERSIONED_LIBS=ON requires BUILD_SHARED_LIBS=ON")
diff --git a/api/include/opentelemetry/version.h b/api/include/opentelemetry/version.h
index 0ff8d71d32..2178591728 100644
--- a/api/include/opentelemetry/version.h
+++ b/api/include/opentelemetry/version.h
@@ -6,10 +6,7 @@
 #include "opentelemetry/common/macros.h"
 #include "opentelemetry/detail/preprocessor.h"
 
-#ifndef OPENTELEMETRY_ABI_VERSION_NO
-#  define OPENTELEMETRY_ABI_VERSION_NO 1
-#endif
-
+#define OPENTELEMETRY_ABI_VERSION_NO 1
 #define OPENTELEMETRY_VERSION "1.9.1"
 #define OPENTELEMETRY_VERSION_MAJOR 1
 #define OPENTELEMETRY_VERSION_MINOR 9
diff --git a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
index bf21d3c1da..a7e0b370d6 100644
--- a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
+++ b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
@@ -53,15 +53,10 @@ class MeterProvider final : public opentelemetry::metrics::MeterProvider
       nostd::string_view version    = "",
       nostd::string_view schema_url = "") noexcept override;
 
-#if OPENTELEMETRY_ABI_VERSION_NO >= 2
+#ifdef ENABLE_REMOVE_METERS_PREVIEW
   void RemoveMeter(nostd::string_view name,
                    nostd::string_view version,
                    nostd::string_view schema_url) noexcept override;
-#else
-  /* Only in the SDK, not API, for ABI VERSION 1 */
-  void RemoveMeter(nostd::string_view name,
-                   nostd::string_view version,
-                   nostd::string_view schema_url) noexcept;
 #endif
 
   /**
diff --git a/sdk/src/metrics/meter_provider.cc b/sdk/src/metrics/meter_provider.cc
index b8720ded15..66d651cce4 100644
--- a/sdk/src/metrics/meter_provider.cc
+++ b/sdk/src/metrics/meter_provider.cc
@@ -57,6 +57,7 @@ nostd::shared_ptr<metrics_api::Meter> MeterProvider::GetMeter(
   return nostd::shared_ptr<metrics_api::Meter>{meter};
 }
 
+#ifdef ENABLE_REMOVE_METERS_PREVIEW
 void MeterProvider::RemoveMeter(nostd::string_view name,
                                 nostd::string_view version,
                                 nostd::string_view schema_url) noexcept
@@ -71,6 +72,7 @@ void MeterProvider::RemoveMeter(nostd::string_view name,
 
   context_->RemoveMeter(name, version, schema_url);
 }
+#endif
 
 const resource::Resource &MeterProvider::GetResource() const noexcept
 {

From 84d2758136f45cf52217df38f5365bad8252daf9 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 3 Jul 2023 15:13:18 +0200
Subject: [PATCH 5/8] CHANGELOG

---
 CHANGELOG.md   | 9 +++++++++
 CMakeLists.txt | 5 +++++
 2 files changed, 14 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 52a9e19f26..e5d15773a3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,6 +21,9 @@ Increment the:
 * [API] Remove include_trace_context
   [#2194](https://github.com/open-telemetry/opentelemetry-cpp/pull/2194)
 
+* [API] Remove Meters
+  [#2205](https://github.com/open-telemetry/opentelemetry-cpp/pull/2205)
+
 Important changes:
 
 * [REMOVAL] Remove the jaeger exporter
@@ -28,6 +31,12 @@ Important changes:
   * The CMake `WITH_JAEGER` option has been removed
   * Please remove usage of `WITH_JAEGER` from user scripts and makefiles.
 
+* [API] Remove Meters
+  [#2205](https://github.com/open-telemetry/opentelemetry-cpp/pull/2205)
+  * The CMake option `WITH_REMOVE_METERS_PREVIEW` was added.
+  * This option is experimental, and may change in the future.
+  * Enabling it is an ABI breaking change.
+
 ## [1.9.1] 2023-05-26
 
 * [DEPRECATION] Drop C++11 support
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 698489a3f1..c5dbb5029b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -197,6 +197,11 @@ option(WITH_OPENTRACING "Whether to include the Opentracing shim" OFF)
 option(OTELCPP_VERSIONED_LIBS "Whether to generate the versioned shared libs"
        OFF)
 
+#
+# This option is experimental, subject to change in the spec:
+#
+# - https://github.com/open-telemetry/opentelemetry-specification/issues/2232
+#
 option(WITH_REMOVE_METERS_PREVIEW
        "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)
 

From 8bd16592cf4acac4b79d86aa104b591ae7e84543 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 3 Jul 2023 15:50:31 +0200
Subject: [PATCH 6/8] Format

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c5dbb5029b..5acce0d72d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -200,7 +200,7 @@ option(OTELCPP_VERSIONED_LIBS "Whether to generate the versioned shared libs"
 #
 # This option is experimental, subject to change in the spec:
 #
-# - https://github.com/open-telemetry/opentelemetry-specification/issues/2232
+# * https://github.com/open-telemetry/opentelemetry-specification/issues/2232
 #
 option(WITH_REMOVE_METERS_PREVIEW
        "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)

From 819d3cf4bd3965cd7695dfff3cd1adce85aa0175 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 3 Jul 2023 16:01:59 +0200
Subject: [PATCH 7/8] Rename to REMOVE_METER (singular)

---
 CHANGELOG.md                                           | 2 +-
 CMakeLists.txt                                         | 4 ++--
 api/CMakeLists.txt                                     | 4 ++--
 api/include/opentelemetry/metrics/meter_provider.h     | 2 +-
 api/include/opentelemetry/metrics/noop.h               | 2 +-
 sdk/include/opentelemetry/sdk/metrics/meter_provider.h | 2 +-
 sdk/src/metrics/meter_provider.cc                      | 2 +-
 7 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e5d15773a3..09da1ca55a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,7 +33,7 @@ Important changes:
 
 * [API] Remove Meters
   [#2205](https://github.com/open-telemetry/opentelemetry-cpp/pull/2205)
-  * The CMake option `WITH_REMOVE_METERS_PREVIEW` was added.
+  * The CMake option `WITH_REMOVE_METER_PREVIEW` was added.
   * This option is experimental, and may change in the future.
   * Enabling it is an ABI breaking change.
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5acce0d72d..997c9440e8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -202,8 +202,8 @@ option(OTELCPP_VERSIONED_LIBS "Whether to generate the versioned shared libs"
 #
 # * https://github.com/open-telemetry/opentelemetry-specification/issues/2232
 #
-option(WITH_REMOVE_METERS_PREVIEW
-       "EXPERIMENTAL, ABI BREAKING: Allow to remove meters" OFF)
+option(WITH_REMOVE_METER_PREVIEW
+       "EXPERIMENTAL, ABI BREAKING: Allow to remove a meter" OFF)
 
 if(OTELCPP_VERSIONED_LIBS AND NOT BUILD_SHARED_LIBS)
   message(FATAL_ERROR "OTELCPP_VERSIONED_LIBS=ON requires BUILD_SHARED_LIBS=ON")
diff --git a/api/CMakeLists.txt b/api/CMakeLists.txt
index 88e0da46fa..d1a6a77fa3 100644
--- a/api/CMakeLists.txt
+++ b/api/CMakeLists.txt
@@ -98,9 +98,9 @@ if(WITH_ASYNC_EXPORT_PREVIEW)
   target_compile_definitions(opentelemetry_api INTERFACE ENABLE_ASYNC_EXPORT)
 endif()
 
-if(WITH_REMOVE_METERS_PREVIEW)
+if(WITH_REMOVE_METER_PREVIEW)
   target_compile_definitions(opentelemetry_api
-                             INTERFACE ENABLE_REMOVE_METERS_PREVIEW)
+                             INTERFACE ENABLE_REMOVE_METER_PREVIEW)
 endif()
 
 # A better place should be in sdk, not api
diff --git a/api/include/opentelemetry/metrics/meter_provider.h b/api/include/opentelemetry/metrics/meter_provider.h
index e1015cb2e3..e0b0285ef4 100644
--- a/api/include/opentelemetry/metrics/meter_provider.h
+++ b/api/include/opentelemetry/metrics/meter_provider.h
@@ -29,7 +29,7 @@ class MeterProvider
   virtual nostd::shared_ptr<Meter> GetMeter(nostd::string_view library_name,
                                             nostd::string_view library_version = "",
                                             nostd::string_view schema_url      = "") noexcept = 0;
-#ifdef ENABLE_REMOVE_METERS_PREVIEW
+#ifdef ENABLE_REMOVE_METER_PREVIEW
   virtual void RemoveMeter(nostd::string_view library_name,
                            nostd::string_view library_version = "",
                            nostd::string_view schema_url      = "") noexcept = 0;
diff --git a/api/include/opentelemetry/metrics/noop.h b/api/include/opentelemetry/metrics/noop.h
index a4b3e10ae9..c5802f3dd3 100644
--- a/api/include/opentelemetry/metrics/noop.h
+++ b/api/include/opentelemetry/metrics/noop.h
@@ -203,7 +203,7 @@ class NoopMeterProvider final : public MeterProvider
     return meter_;
   }
 
-#ifdef ENABLE_REMOVE_METERS_PREVIEW
+#ifdef ENABLE_REMOVE_METER_PREVIEW
   void RemoveMeter(nostd::string_view /* name */,
                    nostd::string_view /* version */,
                    nostd::string_view /* schema_url */) noexcept override
diff --git a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
index a7e0b370d6..4453b5b924 100644
--- a/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
+++ b/sdk/include/opentelemetry/sdk/metrics/meter_provider.h
@@ -53,7 +53,7 @@ class MeterProvider final : public opentelemetry::metrics::MeterProvider
       nostd::string_view version    = "",
       nostd::string_view schema_url = "") noexcept override;
 
-#ifdef ENABLE_REMOVE_METERS_PREVIEW
+#ifdef ENABLE_REMOVE_METER_PREVIEW
   void RemoveMeter(nostd::string_view name,
                    nostd::string_view version,
                    nostd::string_view schema_url) noexcept override;
diff --git a/sdk/src/metrics/meter_provider.cc b/sdk/src/metrics/meter_provider.cc
index 66d651cce4..4b89a5b9b5 100644
--- a/sdk/src/metrics/meter_provider.cc
+++ b/sdk/src/metrics/meter_provider.cc
@@ -57,7 +57,7 @@ nostd::shared_ptr<metrics_api::Meter> MeterProvider::GetMeter(
   return nostd::shared_ptr<metrics_api::Meter>{meter};
 }
 
-#ifdef ENABLE_REMOVE_METERS_PREVIEW
+#ifdef ENABLE_REMOVE_METER_PREVIEW
 void MeterProvider::RemoveMeter(nostd::string_view name,
                                 nostd::string_view version,
                                 nostd::string_view schema_url) noexcept

From c894d5bb4dc5e7f37b500800c04a3ba58ac07da2 Mon Sep 17 00:00:00 2001
From: Marc Alff <marc.alff@oracle.com>
Date: Mon, 10 Jul 2023 10:02:24 +0200
Subject: [PATCH 8/8] Fixed review comments.

---
 ci/do_ci.sh                                 |  3 ++
 sdk/src/metrics/meter_context.cc            |  8 ++++-
 sdk/test/metrics/meter_provider_sdk_test.cc | 37 ++++++++++++++++++++-
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/ci/do_ci.sh b/ci/do_ci.sh
index 42bf3df416..69a6eef0c9 100755
--- a/ci/do_ci.sh
+++ b/ci/do_ci.sh
@@ -106,6 +106,7 @@ elif [[ "$1" == "cmake.maintainer.sync.test" ]]; then
         -DWITH_OTLP_HTTP=ON \
         -DWITH_OTLP_HTTP_SSL_PREVIEW=ON \
         -DWITH_OTLP_HTTP_SSL_TLS_PREVIEW=ON \
+        -DWITH_REMOVE_METER_PREVIEW=ON \
         -DWITH_PROMETHEUS=ON \
         -DWITH_EXAMPLES=ON \
         -DWITH_EXAMPLES_HTTP=ON \
@@ -129,6 +130,7 @@ elif [[ "$1" == "cmake.maintainer.async.test" ]]; then
         -DWITH_OTLP_HTTP=ON \
         -DWITH_OTLP_HTTP_SSL_PREVIEW=ON \
         -DWITH_OTLP_HTTP_SSL_TLS_PREVIEW=ON \
+        -DWITH_REMOVE_METER_PREVIEW=ON \
         -DWITH_PROMETHEUS=ON \
         -DWITH_EXAMPLES=ON \
         -DWITH_EXAMPLES_HTTP=ON \
@@ -153,6 +155,7 @@ elif [[ "$1" == "cmake.maintainer.cpp11.async.test" ]]; then
         -DWITH_OTLP_HTTP=ON \
         -DWITH_OTLP_HTTP_SSL_PREVIEW=ON \
         -DWITH_OTLP_HTTP_SSL_TLS_PREVIEW=ON \
+        -DWITH_REMOVE_METER_PREVIEW=ON \
         -DWITH_PROMETHEUS=ON \
         -DWITH_EXAMPLES=ON \
         -DWITH_EXAMPLES_HTTP=ON \
diff --git a/sdk/src/metrics/meter_context.cc b/sdk/src/metrics/meter_context.cc
index c6526192ef..7a299bfc63 100644
--- a/sdk/src/metrics/meter_context.cc
+++ b/sdk/src/metrics/meter_context.cc
@@ -91,7 +91,13 @@ void MeterContext::RemoveMeter(nostd::string_view name,
   for (auto &meter : meters_)
   {
     auto scope = meter->GetInstrumentationScope();
-    if (!scope->equal(name, version, schema_url))
+    if (scope->equal(name, version, schema_url))
+    {
+      OTEL_INTERNAL_LOG_INFO("[MeterContext::RemoveMeter] removing meter name <"
+                             << name << ">, version <" << version << ">, URL <" << schema_url
+                             << ">");
+    }
+    else
     {
       filtered_meters.push_back(meter);
     }
diff --git a/sdk/test/metrics/meter_provider_sdk_test.cc b/sdk/test/metrics/meter_provider_sdk_test.cc
index bcdc6c4b79..da75916555 100644
--- a/sdk/test/metrics/meter_provider_sdk_test.cc
+++ b/sdk/test/metrics/meter_provider_sdk_test.cc
@@ -16,7 +16,6 @@ using namespace opentelemetry::sdk::metrics;
 
 TEST(MeterProvider, GetMeter)
 {
-
   MeterProvider mp1;
   //   std::unique_ptr<View> view{std::unique_ptr<View>()};
   // MeterProvider mp1(std::move(exporters), std::move(readers), std::move(views);
@@ -59,3 +58,39 @@ TEST(MeterProvider, GetMeter)
   mp1.ForceFlush();
   mp1.Shutdown();
 }
+
+#ifdef ENABLE_REMOVE_METER_PREVIEW
+TEST(MeterProvider, RemoveMeter)
+{
+  MeterProvider mp;
+
+  auto m1 = mp.GetMeter("test", "1", "URL");
+  ASSERT_NE(nullptr, m1);
+
+  // Will return the same meter
+  auto m2 = mp.GetMeter("test", "1", "URL");
+  ASSERT_NE(nullptr, m2);
+  ASSERT_EQ(m1, m2);
+
+  mp.RemoveMeter("unknown", "0", "");
+
+  // Will decrease use_count() on m1 and m2
+  mp.RemoveMeter("test", "1", "URL");
+
+  // Will create a different meter
+  auto m3 = mp.GetMeter("test", "1", "URL");
+  ASSERT_NE(nullptr, m3);
+  ASSERT_NE(m1, m3);
+  ASSERT_NE(m2, m3);
+
+  // Will decrease use_count() on m3
+  mp.RemoveMeter("test", "1", "URL");
+
+  // Will do nothing
+  mp.RemoveMeter("test", "1", "URL");
+
+  // cleanup properly without crash
+  mp.ForceFlush();
+  mp.Shutdown();
+}
+#endif