1.16.0 release notes

19th April 2022

🌟 New features

• Armeria Server now exposes the metrics about TLS handshake results. #4191

  armeria_server_tls_handshakes_total{
    cipher_suite=<the negotiated TLS cipher suite>,
    common_name=<the common name in TLS certificate>,
    protocol=<h1 or h2>,
    result=<success or failure>,
    tls_protocol=<TLS protocol name, e.g. TLSv1.3>
  }

• You can use the @Delimiter annotation in an annotated service to specify the delimiter of a query parameter or header. #4060

  public class MyAnnotatedService {
    // Given the request:
    //   GET /api/v1/users?ids=1,2,3
    // Armeria will inject:
    //   List.of(1, 2, 3)
    // into:
    //   List<Integer> ids
    @Get("/api/v1/users")
    public List<User> getUsers(@Param @Delimiter(",") List<Integer> ids) {
      ...
    }
  }

  • You can also specify a delimiter programmatically with AnnotatedServiceBindingBuilder.queryDelimiter()

• You can now use the no-op subscribe() to drain elements from a StreamMessage #4145 #4185

  // The following statement prints 1, 2 and 3.
  StreamMessage
    .of(1, 2, 3)
    .peek(value -> System.out.println(value))
    .subscribe().join(); // 👈👈👈

• You can now use the response_body option in gRPC-JSON transcoding. #4052 #4132 #4174

  • This option is useful when you need to make a certain response field as a response body. For example, the following Protobuf definition allows you to send a JSON array body whose values are sourced from GetNumbersResponse.myNumberArray:

    service MyService {
      rpc GetNumbers(GetNumbersRequest) returns (GetNumbersResponse) {
        option (google.api.http) = {
          get: "/api/v1/numbers"
          response_body: "my_number_array" // 👈👈👈
        };
      }
    }
    
    message GetNumbersRequest {}
    message GetNumbersResponse {
      repeated string my_number_array = 1; // 👈👈👈
    }

• You can now use the @Decorator annotation to apply decorators to your gRPC stubs. #3967 #4041

  @LoggingDecorator // 👈👈👈
  public class GreeterImpl extends GreeterGrpc.GreeterImplBase {
    @Override
    @RateLimitingDecorator(/* requestsPerSec */ 10.0) // 👈👈👈
    public void sayHello(
      HelloRequest req,
      StreamObserver<HelloReply> responseObserver
    ) {
      responseObserver.onNext(
        HelloReply
          .newBuilder()
          .setMessage(req.getName())
          .build()
      );
      responseObserver.onCompleted();
    }
  }

• AbstractUnaryGrpcService and unframed GrpcService now include the stack trace for failed requests when verboseResponses option is enabled for easier debuggability. #4114 #4171

• You can now specify query parameters additively by calling WebClientRequestPreparation.queryParam() #4173

  // Send GET /api/v1/greet?foo=1&bar=2
  WebClient
    .of().prepare()
    .get("/api/v1/greet")
    .queryParam("foo", "1")
    .queryParams(Map.of("bar", "2")) // 👈👈👈
    .execute()

• You can now override the global Flags by implementing your own FlagsProvider and loading it via Java SPI. #4093 #4151

  package com.example.providers;
  
  // Add the following text file to your classpath or JAR file:
  //
  // $ cat META-INF/services/com.linecorp.armeria.common.FlagsProvider
  // com.example.providers.MyFlagsProvider
  //
  public class MyFlagsProvider implements FlagsProvider {
    @Override
    public int priority() {
      // The provider with higher value will be evaluated first.
      return 100;
    }
  
    @Override
    public int numCommonBlockingTaskThreads() {
        return 100;
    }
  }

• When using armeria-graphql, you can now retrieve the current ServiceRequestContext with GraphqlServiceContexts.get() #4201

  new DataFetcher<>() {
    @Override
    public String get(DataFetchingEnvironment env) throws Exception {
      ServiceRequestContext ctx = GraphqlServiceContexts.get(env);
      ...
    }
  }

• You can now disable the warning message about masked routes when building a Server by specifying the -Dcom.linecorp.armeria.reportMaskedRoutes=false JVM option. #4086

📈 Improvements

• armeria-graphql doesn't use deprecated graphql-java API anymore. #4201
• Less verbose and clearer TLS handshake logging #4181

🛠️ Bug fixes

• JSON-gRPC transcoding now works even if you bind a GrpcService with path prefix. #4086 #4215

  Server
    .builder()
    .route()
      .pathPrefix("/api") // 👈👈👈
      .build(
        GrpcService
          .builder()
          .enableHttpJsonTranscoding(true)
          .addService(...)
          .build()
      )
    .build()

• You now get the HeaderListSizeException as expected when the length of request headers is too long. #4180
• EurekaEndpointGroup now continues refreshing itself even if it failed to refresh once. #4206
• HealthCheckedEndpointGroup now leaves a detailed error message if all endpoints are unhealthy on the first check. #4200
• Fixed a rare infinite loop in EndpointSelectionStrategy.rampingUp() #4219
• The search domain DNS resolver no longer incorrectly resolves a search domain that starts with a dot. #4195 #4196
• Fixed a bug where Armeria server doesn't log the remote address when TLS handshake fails. #4181
• Reduced the cardinality of TLS certificate expiry metrics by using a hostname pattern instead of a hostname as a label. #4191
• TomcatService now records the request start time of CoyoteRequest correctly. #4182 #4183
• You don't get an exception anymore when parsing a multipart request with an empty body. #4175 #4179
• You don't get the noisy warning message about double-completion of future, which occurs when a user misconfigured a ClientFactory #4191

📃 Documentation

• Our build script examples in the website now include Gradle Kotlin DSL. #4106 #4176

🏚️ Deprecations

• Flags.verboseExceptionSamplerSpec() has been deprecated in favor of Flags.verboseExceptionSampler() #4093 #4151

☢️ Breaking changes

• The TLS certificate expiry metrics were renamed from armeria.server.certificate.* to armeria.server.tls.certificate.* for consistency. #4191
  • Also, the hostname label has been replaced with hostname_pattern to reduce the cardinality.
• The return type of Flags.requestContextStorageProvider() was changed from String to RequestContextStorageProvider, so that a user knows which provider will be used exactly. #4093 #4151

⛓ Dependencies

• Brave 5.13.7 → 5.13.8
• Brotli4j 1.6.0 → 1.7.1
• Bucket4j 7.3.0 → 7.4.0
• Dropwizard 2.0.28 → 2.0.29
• gRPC 1.45.0 → 1.45.1
• Jackson 2.13.2 → 2.13.2.1
• java-jwt 3.19.0 → 3.19.1
• Jetty 9.4.45 → 9.4.46
• Kotlin 1.6.10 → 1.6.20
  • Coroutines 1.6.0 → 1.6.1
• Micrometer 1.8.4 → 1.8.5
• Netty 4.1.75 → 4.1.76
• Reactor 3.4.16 → 3.4.17
• Scala 3.1.1 → 3.1.2
• Spring Boot 2.6.5 → 2.6.6
• Tomcat 9.0.56 → 9.0.62, 8.5.77 → 8.5.78

🙇 Thank you