org.apache.pekko.http.impl.util

Class StreamUtils

java.lang.Object

org.apache.pekko.http.impl.util.StreamUtils

public class StreamUtils
extends java.lang.Object

INTERNAL API

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StreamUtils.CaptureMaterializationAndTerminationOp$
static class	StreamUtils.CaptureTerminationOp$
static class	StreamUtils.DelayCancellationStage<T>
static interface	StreamUtils.EntityStreamOp<M>
static interface	StreamUtils.OneTimeValve Similar to Source.maybe but doesn't rely on materialization.
static class	StreamUtils.OneTimeValve$
static interface	StreamUtils.ScheduleSupport
static class	StreamUtils.StreamControl
static class	StreamUtils.StreamControl$

Constructor Summary

Constructors

Constructor and Description
StreamUtils()

Method Summary

Modifier and Type	Method and Description
static org.apache.pekko.stream.stage.GraphStage<org.apache.pekko.stream.FlowShape<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString>>	byteStringTransformer(scala.Function1<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString> f, scala.Function0<org.apache.pekko.util.ByteString> finish) Creates a transformer that will call f for each incoming ByteString and output its result.
static void	cancelSource(org.apache.pekko.stream.scaladsl.Source<?,?> source, org.apache.pekko.stream.Materializer materializer) Tries to guess whether a source needs to cancelled and how.
static <T,Mat> scala.Tuple4<org.apache.pekko.stream.scaladsl.Source<T,Mat>,scala.concurrent.Future<scala.runtime.BoxedUnit>,scala.concurrent.Future<scala.runtime.BoxedUnit>,org.apache.pekko.stream.KillSwitch>	captureMaterializationTerminationAndKillSwitch(org.apache.pekko.stream.scaladsl.Source<T,Mat> source)
static <T,Mat> scala.Tuple2<org.apache.pekko.stream.scaladsl.Source<T,Mat>,scala.concurrent.Future<scala.runtime.BoxedUnit>>	captureTermination(org.apache.pekko.stream.scaladsl.Source<T,Mat> source)
static <T> org.apache.pekko.stream.scaladsl.Flow<T,T,org.apache.pekko.NotUsed>	delayCancellation(scala.concurrent.duration.Duration cancelAfter) INTERNAL API Returns a flow that is almost identity but delays propagation of cancellation from downstream to upstream.
static <T> org.apache.pekko.stream.scaladsl.Flow<T,T,org.apache.pekko.NotUsed>	encodeErrorAndComplete(scala.Function1<java.lang.Throwable,T> f)
static scala.concurrent.Future<org.apache.pekko.stream.IOResult>	handleIOResult(org.apache.pekko.stream.IOResult ioResult) Small helper necessary to deal with errors happening during IO operations like FileIO.toPath.
static org.apache.pekko.stream.stage.GraphStage<org.apache.pekko.stream.FlowShape<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString>>	limitByteChunksStage(int maxBytesPerChunk)
static org.apache.pekko.stream.Materializer	OnlyRunInGraphInterpreterContext() Dummy name to signify that the caller asserts that cancelSource is only run from within a GraphInterpreter context
static org.apache.pekko.stream.scaladsl.Flow<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString,org.apache.pekko.NotUsed>	sliceBytesTransformer(long start, long length)
static <T,U> org.apache.pekko.stream.scaladsl.Flow<T,U,org.apache.pekko.NotUsed>	statefulAttrsMap(scala.Function1<org.apache.pekko.stream.Attributes,scala.Function1<T,U>> functionConstructor) Lifts the streams attributes into an element and passes them to the function for each passed through element.
static <T extends HttpEntity,M> scala.Tuple2<T,M>	transformEntityStream(T entity, StreamUtils.EntityStreamOp<M> streamOp)

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamUtils

public StreamUtils()

Method Detail

byteStringTransformer

public static org.apache.pekko.stream.stage.GraphStage<org.apache.pekko.stream.FlowShape<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString>> byteStringTransformer(scala.Function1<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString> f,
                                                                                                                                                                                   scala.Function0<org.apache.pekko.util.ByteString> finish)

Creates a transformer that will call f for each incoming ByteString and output its result. After the complete input has been read it will call finish once to determine the final ByteString to post to the output. Empty ByteStrings are discarded.

Parameters:

f - (undocumented)

finish - (undocumented)

Returns:

(undocumented)

captureTermination

public static <T,Mat> scala.Tuple2<org.apache.pekko.stream.scaladsl.Source<T,Mat>,scala.concurrent.Future<scala.runtime.BoxedUnit>> captureTermination(org.apache.pekko.stream.scaladsl.Source<T,Mat> source)

captureMaterializationTerminationAndKillSwitch

public static <T,Mat> scala.Tuple4<org.apache.pekko.stream.scaladsl.Source<T,Mat>,scala.concurrent.Future<scala.runtime.BoxedUnit>,scala.concurrent.Future<scala.runtime.BoxedUnit>,org.apache.pekko.stream.KillSwitch> captureMaterializationTerminationAndKillSwitch(org.apache.pekko.stream.scaladsl.Source<T,Mat> source)

sliceBytesTransformer

public static org.apache.pekko.stream.scaladsl.Flow<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString,org.apache.pekko.NotUsed> sliceBytesTransformer(long start,
                                                                                                                                                                      long length)

limitByteChunksStage

public static org.apache.pekko.stream.stage.GraphStage<org.apache.pekko.stream.FlowShape<org.apache.pekko.util.ByteString,org.apache.pekko.util.ByteString>> limitByteChunksStage(int maxBytesPerChunk)

delayCancellation

public static <T> org.apache.pekko.stream.scaladsl.Flow<T,T,org.apache.pekko.NotUsed> delayCancellation(scala.concurrent.duration.Duration cancelAfter)

INTERNAL API

Returns a flow that is almost identity but delays propagation of cancellation from downstream to upstream.

Parameters:

cancelAfter - (undocumented)

Returns:

(undocumented)

statefulAttrsMap

public static <T,U> org.apache.pekko.stream.scaladsl.Flow<T,U,org.apache.pekko.NotUsed> statefulAttrsMap(scala.Function1<org.apache.pekko.stream.Attributes,scala.Function1<T,U>> functionConstructor)

Lifts the streams attributes into an element and passes them to the function for each passed through element. Similar idea than FlowOps.statefulMapConcat but for a simple map.

The result of Attributes => (T => U) is cached, and only the T => U function will be invoked afterwards for each element.

Parameters:

functionConstructor - (undocumented)

Returns:

(undocumented)

OnlyRunInGraphInterpreterContext

public static org.apache.pekko.stream.Materializer OnlyRunInGraphInterpreterContext()

Dummy name to signify that the caller asserts that cancelSource is only run from within a GraphInterpreter context

cancelSource

public static void cancelSource(org.apache.pekko.stream.scaladsl.Source<?,?> source,
                                org.apache.pekko.stream.Materializer materializer)

Tries to guess whether a source needs to cancelled and how. In the best case no materialization should be needed.

Parameters:

source - (undocumented)

materializer - (undocumented)

transformEntityStream

public static <T extends HttpEntity,M> scala.Tuple2<T,M> transformEntityStream(T entity,
                                                                               StreamUtils.EntityStreamOp<M> streamOp)

handleIOResult

public static scala.concurrent.Future<org.apache.pekko.stream.IOResult> handleIOResult(org.apache.pekko.stream.IOResult ioResult)

Small helper necessary to deal with errors happening during IO operations like FileIO.toPath. In these operations, a failure during writing data will be turn into a successful IOResult containing a nested failure.

Here we make sure to unnest errors.

Can be removed when https://github.com/akka/akka/issues/23951 is finally fixed.

Parameters:

ioResult - (undocumented)

Returns:

(undocumented)

encodeErrorAndComplete

public static <T> org.apache.pekko.stream.scaladsl.Flow<T,T,org.apache.pekko.NotUsed> encodeErrorAndComplete(scala.Function1<java.lang.Throwable,T> f)