@VisibleForTesting
    static MethodInfo newMethodInfo(String serviceName, MethodDescriptor method,
                                    Set<EndpointInfo> endpointInfos) {
        return new MethodInfo(
                serviceName,
                method.getName(),
                // gRPC methods always take a single request parameter of message type.
                descriptiveMessageSignature(method.getOutputType()),
                ImmutableList.of(FieldInfo.builder("request",
                                                   descriptiveMessageSignature(method.getInputType()))
                                          .requirement(FieldRequirement.REQUIRED).build()),
                true, ImmutableList.of(),
                endpointInfos,
                ImmutableList.of(),
                defaultExamples(method),
                ImmutableList.of(),
                ImmutableList.of(),
                HttpMethod.POST, DescriptionInfo.empty());
    }
{@link DocServicePlugin} implementation that supports {@link GrpcService}s.
grpc/src/main/java/com/linecorp/armeria/internal/server/grpc/GrpcDocServicePlugin.java