v1.13.0 wasn’t published to maven central due to a releasing process issue and the tag was deleted. The binaries of v1.13.0 were effectively the same as v1.13.1.

Dependencies

• Netty version bumped to 4.1.25-Final and netty-tcnative bumped to 2.0.8.Final
• OpenCensus version bumped to 0.12.3
  • Special thanks: Bogdan Drutu
• Dependency on OpenCensus was removed from the Bazel target io_grpc_grpc_java//core
• services: Use RE2/J
  • Special thanks: Nathan Herring
• alts: Added grpclb runtime

API changes

• Generated RPC Stubs no longer have the static field MethodDescriptors like FOO_METHOD
• ProtoUtils now has metadataMarshaller analogous to ProtoLiteUtils
• Experimental jsonMarshaller has been removed from grpc-java library (and added into examples)
• Added @CheckReturnValue annotation to AbstractStub, CallOptions, and Context
  • Special thanks: Grant Oakley
• CallOptions API: Deprecated CallOptions.Key.of, added CallOptions.Key.create and CallOptions.Key.createWithDefault, and stabilized CallOptions.Key and CallOptions.withOption
• Stabilized ManagedChannelBuilder.maxInboundMessageSize API

New features

• Introduced JUnit test rule GrpcCleanupRule which is more flexible to use than GrpcServerRule
• Channelz Service can now be added to a server to expose stats for all gRPC channels or servers in the process

Behavior changes

• auth: Require PRIVACY_AND_INTEGRITY for GoogleCredentials
• core,stub: Added toString() to ClientCallImpl and GrpcFuture
  • Special thanks: Grant Oakley

Bug fixes

• Fixed Bazel compilation in Java 9
  • Special thanks: David Ostrovsky
• Fixed a bug that client does not detect truncated message
• Fixed a bug of Attributes.hashCode() method
• security: Propagate CallCredentials.ATTR_SECURITY_LEVEL from transports

Documentation

• Documented Metadata ownership passes to the ClientCall and ClientCall.Listener
• Clarified that Android is for client-side use in README.md
• Fixed missing comment for headers param in ServerInterceptor.interceptCall API
  • Special thanks: Jianwei Mao
• Added Kotlin and Kotlin android examples