org.apache.pekko.http.javadsl.model

Interface HttpMessage

All Known Subinterfaces:

HttpMessage

All Known Implementing Classes:

HttpRequest, HttpRequest, HttpResponse, HttpResponse

@DoNotInherit
public interface HttpMessage

The base type for an Http message (request or response).

INTERNAL API: this trait will be changed in binary-incompatible ways for classes that are derived from it! Do not implement this interface outside the Pekko code base!

Binary compatibility is only maintained for callers of this trait’s interface.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	HttpMessage.DiscardedEntity Represents the currently being-drained HTTP Entity which triggers completion of the contained Future once the entity has been drained for the given HttpMessage completely.
static interface	HttpMessage.MessageTransformations<Self>

Method Summary

Modifier and Type	Method and Description
HttpMessage.DiscardedEntity	discardEntityBytes(org.apache.pekko.actor.ClassicActorSystemProvider system) Discards the entities data bytes by running the dataBytes Source contained by the entity of this HTTP message.
HttpMessage.DiscardedEntity	discardEntityBytes(org.apache.pekko.stream.Materializer materializer) Discards the entities data bytes by running the dataBytes Source contained by the entity of this HTTP message.
ResponseEntity	entity() The entity of this message.
<T> java.util.Optional<T>	getAttribute(AttributeKey<T> key) Try to find the attribute for the given key and return Optional.of(attribute), otherwise this method returns an empty Optional.
<T extends HttpHeader> java.util.Optional<T>	getHeader(java.lang.Class<T> headerClass) Try to find the first header of the given class and return Optional.of(header), otherwise this method returns an empty Optional.
java.util.Optional<HttpHeader>	getHeader(java.lang.String headerName) Try to find the first header with the given name (case-insensitive) and return Optional.of(header), otherwise this method returns an empty Optional.
java.lang.Iterable<HttpHeader>	getHeaders() An iterable containing the headers of this message.
<T extends HttpHeader> java.lang.Iterable<T>	getHeaders(java.lang.Class<T> headerClass) An iterable containing all headers of the given class of this message.
boolean	isRequest() Is this instance a request.
boolean	isResponse() Is this instance a response.
HttpProtocol	protocol() The protocol of this message.

Method Detail

isRequest

boolean isRequest()

Is this instance a request.

isResponse

boolean isResponse()

Is this instance a response.

protocol

HttpProtocol protocol()

The protocol of this message.

getHeaders

java.lang.Iterable<HttpHeader> getHeaders()

An iterable containing the headers of this message.

getHeader

java.util.Optional<HttpHeader> getHeader(java.lang.String headerName)

Try to find the first header with the given name (case-insensitive) and return Optional.of(header), otherwise this method returns an empty Optional.

getHeader

<T extends HttpHeader> java.util.Optional<T> getHeader(java.lang.Class<T> headerClass)

Try to find the first header of the given class and return Optional.of(header), otherwise this method returns an empty Optional.

getHeaders

<T extends HttpHeader> java.lang.Iterable<T> getHeaders(java.lang.Class<T> headerClass)

An iterable containing all headers of the given class of this message.

getAttribute

<T> java.util.Optional<T> getAttribute(AttributeKey<T> key)

Try to find the attribute for the given key and return Optional.of(attribute), otherwise this method returns an empty Optional.

entity

ResponseEntity entity()

The entity of this message.

discardEntityBytes

HttpMessage.DiscardedEntity discardEntityBytes(org.apache.pekko.stream.Materializer materializer)

Discards the entities data bytes by running the dataBytes Source contained by the entity of this HTTP message.

Note: It is crucial that entities are either discarded, or consumed by running the underlying [[org.apache.pekko.stream.javadsl.Source]] as otherwise the lack of consuming of the data will trigger back-pressure to the underlying TCP connection (as designed), however possibly leading to an idle-timeout that will close the connection, instead of just having ignored the data.

Warning: It is not allowed to discard and/or consume the entity.dataBytes more than once as the stream is directly attached to the "live" incoming data source from the underlying TCP connection. Allowing it to be consumable twice would require buffering the incoming data, thus defeating the purpose of its streaming nature. If the dataBytes source is materialized a second time, it will fail with an "stream can cannot be materialized more than once" exception.

When called on `Strict` entities or sources whose values can be buffered in memory, the above warnings can be ignored. Repeated materialization is not necessary in this case, avoiding the mentioned exceptions due to the data being held in memory.

In future versions, more automatic ways to warn or resolve these situations may be introduced, see issue #18716.

discardEntityBytes

HttpMessage.DiscardedEntity discardEntityBytes(org.apache.pekko.actor.ClassicActorSystemProvider system)

Discards the entities data bytes by running the dataBytes Source contained by the entity of this HTTP message.

Note: It is crucial that entities are either discarded, or consumed by running the underlying [[org.apache.pekko.stream.javadsl.Source]] as otherwise the lack of consuming of the data will trigger back-pressure to the underlying TCP connection (as designed), however possibly leading to an idle-timeout that will close the connection, instead of just having ignored the data.

Warning: It is not allowed to discard and/or consume the entity.dataBytes more than once as the stream is directly attached to the "live" incoming data source from the underlying TCP connection. Allowing it to be consumable twice would require buffering the incoming data, thus defeating the purpose of its streaming nature. If the dataBytes source is materialized a second time, it will fail with an "stream can cannot be materialized more than once" exception.

When called on `Strict` entities or sources whose values can be buffered in memory, the above warnings can be ignored. Repeated materialization is not necessary in this case, avoiding the mentioned exceptions due to the data being held in memory.

In future versions, more automatic ways to warn or resolve these situations may be introduced, see issue #18716.