Package io.smallrye.mutiny.helpers.spies

Interface Spy

@Experimental("We are experimenting with spies for diagnosis and testing")
public interface Spy

Helpers for creating Uni and Multi spies to observe events. A spy is a transparent operator that can be plugged into a pipeline to help diagnose what events flow. It observes how many times a given event has been observed. Depending on the event type it will also report values, such as the last observed failure or termination. It is important to note that spies observe and report events for all subscribers, not just one in particular.

Method Summary

Static Methods

Modifier and Type	Method	Description
static <T> MultiGlobalSpy<T>	globally(Multi<T> upstream)	Spy all Multi events (except Multi.onOverflow()).
static <T> UniGlobalSpy<T>	globally(Uni<T> upstream)	Spy all Uni events.
static <T> MultiOnCancellationSpy<T>	onCancellation(Multi<T> upstream)	Spy Multi.onCancellation() events.
static <T> UniOnCancellationSpy<T>	onCancellation(Uni<T> upstream)	Spy Uni.onCancellation() events.
static <T> MultiOnCompletionSpy<T>	onCompletion(Multi<T> upstream)	Spy Multi.onCompletion() events.
static <T> MultiOnFailureSpy<T>	onFailure(Multi<T> upstream)	Spy Multi.onFailure() events.
static <T> MultiOnFailureSpy<T>	onFailure(Multi<T> upstream, java.lang.Class<? extends java.lang.Throwable> typeOfFailure)	Spy Multi.onFailure(Class) events.
static <T> MultiOnFailureSpy<T>	onFailure(Multi<T> upstream, java.util.function.Predicate<? super java.lang.Throwable> predicate)	Spy Multi.onFailure(Predicate) events.
static <T> UniOnFailureSpy<T>	onFailure(Uni<T> upstream)	Spy Uni.onFailure() events.
static <T> UniOnFailureSpy<T>	onFailure(Uni<T> upstream, java.lang.Class<? extends java.lang.Throwable> typeOfFailure)	Spy Uni.onFailure(Class) events.
static <T> UniOnFailureSpy<T>	onFailure(Uni<T> upstream, java.util.function.Predicate<? super java.lang.Throwable> predicate)	Spy Uni.onFailure(Predicate) )} events.
static <T> MultiOnItemSpy<T>	onItem(Multi<T> upstream)	Spy Multi.onItem() events and keep track of the items.
static <T> MultiOnItemSpy<T>	onItem(Multi<T> upstream, boolean trackItems)	Spy Multi.onItem() events and optionally keep track of the items.
static <T> UniOnItemSpy<T>	onItem(Uni<T> upstream)	Spy Uni.onItem() events.
static <T> UniOnItemOrFailureSpy<T>	onItemOrFailure(Uni<T> upstream)	Spy Uni.onItemOrFailure() events.
static <T> MultiOnOverflowSpy<T>	onOverflow(Multi<T> upstream, boolean trackItems, java.util.function.Function<MultiOverflowStrategy<? extends T>,Multi<? extends T>> strategyMapper)	Spy Multi.onOverflow() events and track dropped items.
static <T> MultiOnOverflowSpy<T>	onOverflow(Multi<T> upstream, java.util.function.Function<MultiOverflowStrategy<? extends T>,Multi<? extends T>> strategyMapper)	Spy Multi.onOverflow() events and track dropped items.
static <T> MultiOnRequestSpy<T>	onRequest(Multi<T> upstream)	Spy Multi.onRequest() events.
static <T> MultiOnSubscribeSpy<T>	onSubscribe(Multi<T> upstream)	Spy Multi.onSubscription() events.
static <T> UniOnSubscribeSpy<T>	onSubscribe(Uni<T> upstream)	Spy Uni.onSubscription() events.
static <T> MultiOnTerminationSpy<T>	onTermination(Multi<T> upstream)	Spy Multi.onTermination() events.
static <T> UniOnTerminationSpy<T>	onTermination(Uni<T> upstream)	Spy Uni.onTermination() events.

Method Detail

onSubscribe

static <T> UniOnSubscribeSpy<T> onSubscribe(Uni<T> upstream)

Spy Uni.onSubscription() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onCancellation

static <T> UniOnCancellationSpy<T> onCancellation(Uni<T> upstream)

Spy Uni.onCancellation() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onTermination

static <T> UniOnTerminationSpy<T> onTermination(Uni<T> upstream)

Spy Uni.onTermination() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onItem

static <T> UniOnItemSpy<T> onItem(Uni<T> upstream)

Spy Uni.onItem() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onItemOrFailure

static <T> UniOnItemOrFailureSpy<T> onItemOrFailure(Uni<T> upstream)

Spy Uni.onItemOrFailure() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onFailure

static <T> UniOnFailureSpy<T> onFailure(Uni<T> upstream)

Spy Uni.onFailure() events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onFailure

static <T> UniOnFailureSpy<T> onFailure(Uni<T> upstream,
                                        java.util.function.Predicate<? super java.lang.Throwable> predicate)

Spy Uni.onFailure(Predicate) )} events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

predicate - a predicate to match a failure type

Returns:

a new Uni

onFailure

static <T> UniOnFailureSpy<T> onFailure(Uni<T> upstream,
                                        java.lang.Class<? extends java.lang.Throwable> typeOfFailure)

Spy Uni.onFailure(Class) events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

typeOfFailure - the expected failure type

Returns:

a new Uni

globally

static <T> UniGlobalSpy<T> globally(Uni<T> upstream)

Spy all Uni events.

Type Parameters:

T - the item type

Parameters:

upstream - the upstream

Returns:

a new Uni

onCancellation

static <T> MultiOnCancellationSpy<T> onCancellation(Multi<T> upstream)

Spy Multi.onCancellation() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onCompletion

static <T> MultiOnCompletionSpy<T> onCompletion(Multi<T> upstream)

Spy Multi.onCompletion() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onFailure

static <T> MultiOnFailureSpy<T> onFailure(Multi<T> upstream)

Spy Multi.onFailure() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onFailure

static <T> MultiOnFailureSpy<T> onFailure(Multi<T> upstream,
                                          java.util.function.Predicate<? super java.lang.Throwable> predicate)

Spy Multi.onFailure(Predicate) events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

predicate - a predicate to match a failure type

Returns:

a new Multi

onFailure

static <T> MultiOnFailureSpy<T> onFailure(Multi<T> upstream,
                                          java.lang.Class<? extends java.lang.Throwable> typeOfFailure)

Spy Multi.onFailure(Class) events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

typeOfFailure - the type of failure

Returns:

a new Multi

onItem

static <T> MultiOnItemSpy<T> onItem(Multi<T> upstream)

Spy Multi.onItem() events and keep track of the items.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onItem

static <T> MultiOnItemSpy<T> onItem(Multi<T> upstream,
                                    boolean trackItems)

Spy Multi.onItem() events and optionally keep track of the items.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

trackItems - true when items shall be tracked, false otherwise

Returns:

a new Multi

onRequest

static <T> MultiOnRequestSpy<T> onRequest(Multi<T> upstream)

Spy Multi.onRequest() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onSubscribe

static <T> MultiOnSubscribeSpy<T> onSubscribe(Multi<T> upstream)

Spy Multi.onSubscription() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onTermination

static <T> MultiOnTerminationSpy<T> onTermination(Multi<T> upstream)

Spy Multi.onTermination() events.

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi

onOverflow

static <T> MultiOnOverflowSpy<T> onOverflow(Multi<T> upstream,
                                            java.util.function.Function<MultiOverflowStrategy<? extends T>,Multi<? extends T>> strategyMapper)

Spy Multi.onOverflow() events and track dropped items.

Type Parameters:

T - the items type

Parameters:

upstream - the uptream

strategyMapper - a function to define the drop strategy applied by the spy

Returns:

a new Multi

onOverflow

static <T> MultiOnOverflowSpy<T> onOverflow(Multi<T> upstream,
                                            boolean trackItems,
                                            java.util.function.Function<MultiOverflowStrategy<? extends T>,Multi<? extends T>> strategyMapper)

Spy Multi.onOverflow() events and track dropped items.

Type Parameters:

T - the items type

Parameters:

upstream - the uptream

trackItems - true if items shall be tracked, false otherwise

strategyMapper - a function to define the drop strategy applied by the spy

Returns:

a new Multi

globally

static <T> MultiGlobalSpy<T> globally(Multi<T> upstream)

Spy all Multi events (except Multi.onOverflow()). The overflow events are not being tracked because they cause the upstream to be requested Long.MAX_VALUE elements, so the behavior of a pipeline can be affected by introducing a MultiOnOverflowSpy. If you want to track overflow events then you will need to explicitly wrap a Multi with onOverflow(Multi, Function).

Type Parameters:

T - the items type

Parameters:

upstream - the upstream

Returns:

a new Multi