v1.9.1 release

Release of core packages

• opentelemetry-api
• opentelemetry-sdk

and exporter packages:

• opentelemetry-exporter-otlp (gRPC + HTTP/JSON)

NEW DEPRECATION

• [DEPRECATION] Drop C++11 support #2146

CI

• [CI] Upgrade Bazel and Bazelisk version #2118
• [CI] Upgrade Google Benchmark version from 1.6.0 to 1.7.1 #2116
• [CI] Upgrade Nlohmann JSON library version from 3.10.5 to 3.11.2 #2115

BUILD

• [BUILD] Missed include #2143
• [BUILD] Add opentelemetry_proto_grpc and allow build shared opentelemetry_proto and opentelemetry_proto_grpc on non-Windows platform. #2097
• [BUILD] Warning cleanup, single character wrapped by std::string #2137
• [BUILD] Add missing target dependencies #2128
• [BUILD] Fix if JSON library already added another CMake target #2126
• [BUILD] shared libraries with version suffix, along with the symbolic link #2109
• [BUILD] Show warning message if WITH_OTLP is enabled #2112
• [BUILD] Add missing STL header. #2107
• [BUILD] Build break with old curl, macro CURL_VERSION_BITS unknown #2102
• [BUILD] Transitive dependency issue with the otlp http exporter #2154

TEST

• [TEST] Add unit test for log body implicit conversions. #2136
• [TEST] Add event id to logger benchmark method #2133

API

• [API] Fix inclusion header files and use forward declaration #2124
• [API] Add user facing Logging API and Benchmarks #2094

SDK

• [SDK] SDK support for the new OTel log #2123

EXPORTER

• [EXPORTER] Fixed HTTP session cleanup on shutdown #2111
• [EXPORTER] Delegate all API calls of gRPC into opentelemetry_exporter_otlp_grpc_client, and make it contains all symbols needed. #2005

DOC

• [DOC] Add Marc as maintainer. #2027

Breaking changes

• Add opentelemetry_proto_grpc and move gRPC sources into it. #2097
  • There will be no breaking changes for users who only use OTLP exporters and do not directly use opentelemetry-cpp::proto. However, it is important to note that opentelemetry-cpp::proto no longer contains generated gRPC codes, and all components that depend on these gRPC codes should also link to opentelemetry-cpp::proto_grpc.

All Deprecations

• The Jaeger Exporter is deprecated, see DEPRECATED for details.
• C++11 support is to end, C++14 will be supported instead, see DEPRECATED for details.

Full Changelog: https://github.com/open-telemetry/opentelemetry-cpp/compare/v1.9.0...v1.9.1