Package com.linecorp.armeria.server.protobuf

Class ProtobufResponseConverterFunction

java.lang.Object

com.linecorp.armeria.server.protobuf.ProtobufResponseConverterFunction

All Implemented Interfaces:

ResponseConverterFunction

@UnstableApi
public final class ProtobufResponseConverterFunction
extends Object
implements ResponseConverterFunction

A ResponseConverterFunction which creates an HttpResponse with content-type: application/protobuf or content-type: application/json; charset=utf-8. If the returned object is an instance of MessageLite, the object can be converted to either Protocol Buffers or JSON format.

Conversion of multiple Protobuf messages

A sequence of Protocol Buffer messages can not be handled by this ResponseConverterFunction, because Protocol Buffers wire format is not self-delimiting. See Streaming Multiple Messages for more information. However, Publisher, Stream and Iterable are supported when converting to JSON array. JavaScript Object Notation (JSON) Text Sequences is also supported for Publisher, Stream.

Note that this ResponseConverterFunction is applied to an annotated service by default, so you don't have to specify this converter explicitly unless you want to use your own JsonFormat.Printer. The JsonFormat.printer() is used by default to format the response content.

Constructor Summary

Constructors

Constructor	Description
ProtobufResponseConverterFunction()	Creates an instance with the default JsonFormat.Printer.
ProtobufResponseConverterFunction(JsonFormat.Printer jsonPrinter)	Creates an instance with the specified JsonFormat.Printer.

Method Summary

Modifier and Type	Method	Description
HttpResponse	convertResponse(ServiceRequestContext ctx, ResponseHeaders headers, @Nullable Object result, HttpHeaders trailers)	Returns HttpResponse instance corresponds to the given result.
Boolean	isResponseStreaming(Type returnType, @Nullable MediaType produceType)	Returns whether an HttpResponse of an annotated service should be streamed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ProtobufResponseConverterFunction

public ProtobufResponseConverterFunction()

Creates an instance with the default JsonFormat.Printer.

ProtobufResponseConverterFunction

public ProtobufResponseConverterFunction(JsonFormat.Printer jsonPrinter)

Creates an instance with the specified JsonFormat.Printer.

Method Details

isResponseStreaming

public Boolean isResponseStreaming(Type returnType,
 @Nullable
 @Nullable MediaType produceType)

Description copied from interface: ResponseConverterFunction

Returns whether an HttpResponse of an annotated service should be streamed. null if this converter cannot convert the responseType to an HttpResponse. true can be returned if the response is a streaming type, or the ResponseConverterFunction has not been optimized for the responseType through overriding this method for backward compatibility.

This method is used as a performance optimization hint. If the returnType and produceType are not a streaming response, it is recommended to return false for the better performance.

Note that you should never return false for a streaming response. The non-streaming response is aggregated before being sent.

Specified by:

isResponseStreaming in interface ResponseConverterFunction

Parameters:

returnType - the return type of the annotated service.

produceType - the negotiated producible media type of the annotated service. null if the media type negotiation is not used for the service.

convertResponse

public HttpResponse convertResponse(ServiceRequestContext ctx,
 ResponseHeaders headers,
 @Nullable
 @Nullable Object result,
 HttpHeaders trailers)
                             throws Exception

Description copied from interface: ResponseConverterFunction

Returns HttpResponse instance corresponds to the given result. Calls ResponseConverterFunction.fallthrough() if this converter cannot convert the result to the HttpResponse.

Specified by:

convertResponse in interface ResponseConverterFunction

Parameters:

headers - The HTTP headers that you might want to use to create the HttpResponse. The status of headers is HttpStatus.OK by default or HttpStatus.NO_CONTENT if the annotated method returns void, unless you specify it with StatusCode on the method. The headers also will include a MediaType if ServiceRequestContext.negotiatedResponseMediaType() returns it. If the annotated method returns an HttpResult or a ResponseEntity, the headers provided by them will be given as they are. Please note that the additional headers set by ServiceRequestContext.mutateAdditionalResponseHeaders(Consumer) and AdditionalHeader are not included in this headers.

result - The result of the service method.

trailers - The HTTP trailers that you might want to use to create the HttpResponse. If the annotated method returns an HttpResult or a ResponseEntity, the trailers provided by them will be given as they are. Please note that the additional trailers set by ServiceRequestContext.mutateAdditionalResponseTrailers(Consumer) and AdditionalTrailer are not included in this trailers.

Throws:

Exception