Release v1.75.0

This is release 1.75.0 (gemini) of gRPC Core.

For gRPC documentation, see grpc.io. For previous releases, see Releases.

This release contains refinements, improvements, and bug fixes, with highlights listed below.

Core

• [Security] Cherry Pick Spiffe Verification. (#40515)
• [Python][Typeguard] Part 3 - Add Typeguard to AIO stack in tests. (#40217)
• [c-ares] update version to 1.34.5. (#39508)
• [pick_first] fix bug that caused us to stop attempting to connect. (#40162)

C++

• [OTel C++] Implement retry metrics. (#39195)

Objective-C

• Fix data race by adding custom getter for state property with @synchronized locking. (#40146)

Python

• gRPC Python (grpcio) now depends on typing-extensions~=4.13. (#40137)
• Update musllinux wheels from musllinux_1_1 to musllinux_1_2. (#40317)
  • Dropping musllinux_1_1 because it reached EOL in November 2024
  • Reference on musllinux platform tags: PEP 656
• grpc.aio typehint fixes. (#40215, #40217)
  • Metadata type validation: Fixed metadata handling to support all sequence types (not just tuples), preventing runtime errors. Enhanced metadata type validation: isinstance(metadata, Sequence) instead of isinstance(metadata, tuple)
  • Serializer parameters: Changed to Optional[SerializingFunction] for more accurate type representation
  • Fixing the error in public API: ClientCallDetails.method was declared as str but always called with bytes, see InterceptedUnaryUnaryCall.
• Fixes issue #40325 with grpcio failing to install on all non-Mac Apple devices internal builds. (#40347)

Ruby

• Ruby: Mark credential object in channel. (#40394)
• [Ruby] Add rubygems support for linux-gnu and linux-musl platforms. (#39549)