v1.16.0

April 19, 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