Package io.servicetalk.http.utils

Class CacheConnectionHttpLoadBalanceFactory<ResolvedAddress>

java.lang.Object

io.servicetalk.http.utils.CacheConnectionHttpLoadBalanceFactory<ResolvedAddress>

Type Parameters:

ResolvedAddress - The resolved address type.

All Implemented Interfaces:

LoadBalancerFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection>, HttpLoadBalancerFactory<ResolvedAddress>, ExecutionStrategyInfluencer<ExecutionStrategy>

public final class CacheConnectionHttpLoadBalanceFactory<ResolvedAddress>
extends Object
implements HttpLoadBalancerFactory<ResolvedAddress>

A HttpLoadBalancerFactory that will cache successive connection creation attempts and return the same Single instead of creating a new connection each time. This is useful when a spike of connections occurs instead of creating a new connection for each request, if the underlying protocol version supports concurrency (pipelining, multiplexing) a single connection creation attempt can be used before the connection is actually established, which will reduce the overall number of connections required.

Nested Class Summary

Nested classes/interfaces inherited from interface io.servicetalk.http.api.HttpLoadBalancerFactory

HttpLoadBalancerFactory.DefaultFilterableStreamingHttpLoadBalancedConnection

Constructor Summary

Constructors

Constructor	Description
CacheConnectionHttpLoadBalanceFactory(HttpLoadBalancerFactory<ResolvedAddress> delegate, ToIntFunction<ResolvedAddress> maxConcurrencyFunc)	Create a new instance.

Method Summary

Modifier and Type	Method	Description
LoadBalancer<FilterableStreamingHttpLoadBalancedConnection>	newLoadBalancer(Publisher<? extends Collection<? extends ServiceDiscovererEvent<ResolvedAddress>>> eventPublisher, ConnectionFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection> connectionFactory, String targetResource)	Create a new LoadBalancer.
<T extends FilterableStreamingHttpLoadBalancedConnection> LoadBalancer<T>	newLoadBalancer(String targetResource, Publisher<? extends Collection<? extends ServiceDiscovererEvent<ResolvedAddress>>> eventPublisher, ConnectionFactory<ResolvedAddress,T> connectionFactory)	Create a new LoadBalancer.
HttpExecutionStrategy	requiredOffloads()	Return an ExecutionStrategy that describes the offloads required by the influencer.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.servicetalk.http.api.HttpLoadBalancerFactory

toLoadBalancedConnection, toLoadBalancedConnection

Methods inherited from interface io.servicetalk.client.api.LoadBalancerFactory

newLoadBalancer

Constructor Details

CacheConnectionHttpLoadBalanceFactory

public CacheConnectionHttpLoadBalanceFactory(HttpLoadBalancerFactory<ResolvedAddress> delegate,
 ToIntFunction<ResolvedAddress> maxConcurrencyFunc)

Create a new instance.

Parameters:

delegate - The LoadBalancerFactory to delegate to.

maxConcurrencyFunc - The default number of maximum concurrency requests per each address.

Method Details

newLoadBalancer

public <T extends FilterableStreamingHttpLoadBalancedConnection>
LoadBalancer<T> newLoadBalancer(String targetResource,
 Publisher<? extends Collection<? extends ServiceDiscovererEvent<ResolvedAddress>>> eventPublisher,
 ConnectionFactory<ResolvedAddress,T> connectionFactory)

Description copied from interface: LoadBalancerFactory

Create a new LoadBalancer.

Specified by:

newLoadBalancer in interface LoadBalancerFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection>

Type Parameters:

T - Type of connections created by the passed ConnectionFactory.

Parameters:

targetResource - A String representation of the target resource for which the created instance will perform load balancing. Bear in mind, load balancing is performed over the a collection of hosts provided via the eventPublisher which may not correspond directly to a single unresolved address, but potentially a merged collection.

eventPublisher - A stream of Collection<ServiceDiscovererEvent> which the LoadBalancer can use to connect to physical hosts. Typically generated from ServiceDiscoverer.

connectionFactory - ConnectionFactory that the returned LoadBalancer will use to generate new connections. Returned LoadBalancer will own the responsibility for this ConnectionFactory and hence will call AsyncCloseable.closeAsync() when AsyncCloseable.closeAsync() is called.

Returns:

a new LoadBalancer.

newLoadBalancer

public LoadBalancer<FilterableStreamingHttpLoadBalancedConnection> newLoadBalancer(Publisher<? extends Collection<? extends ServiceDiscovererEvent<ResolvedAddress>>> eventPublisher,
 ConnectionFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection> connectionFactory,
 String targetResource)

Description copied from interface: LoadBalancerFactory

Create a new LoadBalancer.

Specified by:

newLoadBalancer in interface LoadBalancerFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection>

Parameters:

eventPublisher - A stream of Collection<ServiceDiscovererEvent> which the LoadBalancer can use to connect to physical hosts. Typically generated from ServiceDiscoverer.

connectionFactory - ConnectionFactory that the returned LoadBalancer will use to generate new connections. Returned LoadBalancer will own the responsibility for this ConnectionFactory and hence will call AsyncCloseable.closeAsync() when AsyncCloseable.closeAsync() is called.

targetResource - A String representation of the target resource for which the created instance will perform load balancing. Bear in mind, load balancing is performed over the collection of hosts provided via the eventPublisher which may not correspond directly to a single unresolved address, but potentially a merged collection.

Returns:

a new LoadBalancer.

requiredOffloads

public HttpExecutionStrategy requiredOffloads()

Description copied from interface: ExecutionStrategyInfluencer

Return an ExecutionStrategy that describes the offloads required by the influencer.

Specified by:

requiredOffloads in interface ExecutionStrategyInfluencer<ResolvedAddress>

Specified by:

requiredOffloads in interface HttpLoadBalancerFactory<ResolvedAddress>

Specified by:

requiredOffloads in interface LoadBalancerFactory<ResolvedAddress,FilterableStreamingHttpLoadBalancedConnection>

Returns:

the ExecutionStrategy required by the influencer.