org.springframework.http.client.reactive.ReactorClientHttpConnector Maven / Gradle / Ivy
/*
* Copyright 2002-2023 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.http.client.reactive;
import java.net.URI;
import java.util.concurrent.atomic.AtomicReference;
import java.util.function.Function;
import reactor.core.publisher.Mono;
import reactor.netty.NettyOutbound;
import reactor.netty.http.client.HttpClient;
import reactor.netty.http.client.HttpClientRequest;
import reactor.netty.resources.ConnectionProvider;
import reactor.netty.resources.LoopResources;
import org.springframework.http.HttpMethod;
import org.springframework.util.Assert;
/**
* Reactor-Netty implementation of {@link ClientHttpConnector}.
*
* @author Brian Clozel
* @author Rossen Stoyanchev
* @since 5.0
* @see reactor.netty.http.client.HttpClient
*/
public class ReactorClientHttpConnector implements ClientHttpConnector {
private final static Function defaultInitializer = client -> client.compress(true);
private final HttpClient httpClient;
/**
* Default constructor. Initializes {@link HttpClient} via:
*
* HttpClient.create().compress()
*
*/
public ReactorClientHttpConnector() {
this.httpClient = defaultInitializer.apply(HttpClient.create());
}
/**
* Constructor with externally managed Reactor Netty resources, including
* {@link LoopResources} for event loop threads, and {@link ConnectionProvider}
* for the connection pool.
* This constructor should be used only when you don't want the client
* to participate in the Reactor Netty global resources. By default the
* client participates in the Reactor Netty global resources held in
* {@link reactor.netty.http.HttpResources}, which is recommended since
* fixed, shared resources are favored for event loop concurrency. However,
* consider declaring a {@link ReactorResourceFactory} bean with
* {@code globalResources=true} in order to ensure the Reactor Netty global
* resources are shut down when the Spring ApplicationContext is closed.
* @param factory the resource factory to obtain the resources from
* @param mapper a mapper for further initialization of the created client
* @since 5.1
*/
public ReactorClientHttpConnector(ReactorResourceFactory factory, Function mapper) {
ConnectionProvider provider = factory.getConnectionProvider();
Assert.notNull(provider, "No ConnectionProvider: is ReactorResourceFactory not initialized yet?");
this.httpClient = defaultInitializer.andThen(mapper).andThen(applyLoopResources(factory))
.apply(HttpClient.create(provider));
}
private static Function applyLoopResources(ReactorResourceFactory factory) {
return httpClient -> {
LoopResources resources = factory.getLoopResources();
Assert.notNull(resources, "No LoopResources: is ReactorResourceFactory not initialized yet?");
return httpClient.runOn(resources);
};
}
/**
* Constructor with a pre-configured {@code HttpClient} instance.
* @param httpClient the client to use
* @since 5.1
*/
public ReactorClientHttpConnector(HttpClient httpClient) {
Assert.notNull(httpClient, "HttpClient is required");
this.httpClient = httpClient;
}
@Override
public Mono connect(HttpMethod method, URI uri,
Function> requestCallback) {
AtomicReference responseRef = new AtomicReference<>();
HttpClient.RequestSender requestSender = this.httpClient
.request(io.netty.handler.codec.http.HttpMethod.valueOf(method.name()));
requestSender = setUri(requestSender, uri);
return requestSender
.send((request, outbound) -> requestCallback.apply(adaptRequest(method, uri, request, outbound)))
.responseConnection((response, connection) -> {
responseRef.set(new ReactorClientHttpResponse(response, connection));
return Mono.just((ClientHttpResponse) responseRef.get());
})
.next()
.doOnCancel(() -> {
ReactorClientHttpResponse response = responseRef.get();
if (response != null) {
response.releaseAfterCancel(method);
}
});
}
private static HttpClient.RequestSender setUri(HttpClient.RequestSender requestSender, URI uri) {
if (uri.isAbsolute()) {
try {
return requestSender.uri(uri);
}
catch (Exception ex) {
// Fall back on passing it in as a String
}
}
return requestSender.uri(uri.toString());
}
private ReactorClientHttpRequest adaptRequest(HttpMethod method, URI uri, HttpClientRequest request,
NettyOutbound nettyOutbound) {
return new ReactorClientHttpRequest(method, uri, request, nettyOutbound);
}
}