Package org.axonframework.messaging.queryhandling.distributed

Interface QueryBusConnector

All Superinterfaces:

DescribableComponent

All Known Implementing Classes:

AxonServerQueryBusConnector, DelegatingQueryBusConnector, PayloadConvertingQueryBusConnector

public interface QueryBusConnector
extends DescribableComponent

The QueryBusConnector interface defines the contract for connecting multiple QueryBus instances.

It allows for the dispatching of queries across different query bus instances, whether they are local or remote. One connector can be wrapped with another through the DelegatingQueryBusConnector, upon which more functionality can be added, such as payload conversion or conversion.

Since:

5.0.0

Author:

Steven van Beelen

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	QueryBusConnector.Handler	Defines a handler for processing query messages and managing subscription queries.
static interface	QueryBusConnector.UpdateCallback	Defines a callback mechanism to handle update messages for subscription queries in a reactive and asynchronous manner.

Method Summary

Modifier and Type	Method	Description
void	onIncomingQuery(QueryBusConnector.Handler handler)	Registers a handler to process incoming query messages.
MessageStream<QueryResponseMessage>	query(QueryMessage query, ProcessingContext context)	Sends the given query to the remote QueryBus.
CompletableFuture<Void>	subscribe(QualifiedName name)	Subscribes this connector to queries matching the given name.
MessageStream<QueryResponseMessage>	subscriptionQuery(QueryMessage query, ProcessingContext context, int updateBufferSize)	Sends the given query to the remote QueryBus.
boolean	unsubscribe(QualifiedName name)	Unsubscribes this connector from queries with the given name.

Methods inherited from interface org.axonframework.common.infra.DescribableComponent

describeTo

Method Details

query

@Nonnull
MessageStream<QueryResponseMessage> query(@Nonnull
 QueryMessage query,
 @Nullable
 ProcessingContext context)

Sends the given query to the remote QueryBus.

Parameters:

query - The query to send to the remote QueryBus.

context - The context, if available, in which the query is generated

Returns:

the stream of responses for the query

See Also:

• QueryBus.query(QueryMessage, ProcessingContext)

subscriptionQuery

@Nonnull
MessageStream<QueryResponseMessage> subscriptionQuery(@Nonnull
 QueryMessage query,
 @Nullable
 ProcessingContext context,
 int updateBufferSize)

Sends the given query to the remote QueryBus.

Parameters:

query - The query to send to the remote QueryBus.

context - The context, if available, in which the query is generated

updateBufferSize - The size of the buffer used to store update for the subscription query.

Returns:

the stream of responses for the query

See Also:

• QueryBus.subscriptionQuery(QueryMessage, ProcessingContext, int)

subscribe

CompletableFuture<Void> subscribe(@Nonnull
 QualifiedName name)

Subscribes this connector to queries matching the given name.

Parameters:

name - The QualifiedName of the Message.type() to subscribe to.

Returns:

A CompletableFuture that completes successfully when this connector subscribed to the given name.

unsubscribe

boolean unsubscribe(@Nonnull
 QualifiedName name)

Unsubscribes this connector from queries with the given name.

Parameters:

name - The QualifiedName of the Message.type() to unsubscribe from.

Returns:

true if unsubscribing was successful, false otherwise.

onIncomingQuery

void onIncomingQuery(@Nonnull
 QueryBusConnector.Handler handler)

Registers a handler to process incoming query messages.

Parameters:

handler - The handler responsible for managing incoming queries.