Configuration
创建 WebClient
最简单的方法是通过静态工厂方法之一:
-
WebClient.create()
-
WebClient.create(String baseUrl)
此外,你还可以使用 WebClient.builder()
加上其他选项:
-
uriBuilderFactory
:自定义 `UriBuilderFactory`以用作基本 URL。 -
defaultUriVariables
:展开 URI 模板时要使用的默认值。 -
defaultHeader
:每个请求的标头。 -
defaultCookie
:每个请求的 cookie。 -
defaultRequest
: `Consumer`以自定义每个请求。 -
filter
:每个请求的客户端过滤器。 -
exchangeStrategies
:HTTP 消息读取器/写入器自定义。 -
clientConnector
:HTTP 客户端库设置。 -
observationRegistry
:用于启用 Observability support的注册表。 -
observationConvention
:已记录观测的 an optional, custom convention to extract metadata。
例如:
-
Java
-
Kotlin
WebClient client = WebClient.builder()
.codecs(configurer -> ... )
.build();
val webClient = WebClient.builder()
.codecs { configurer -> ... }
.build()
一旦构建完毕,一个 WebClient
就是不可变的。但是,你可以像以下代码一样克隆它并构建一个已修改的副本:
-
Java
-
Kotlin
WebClient client1 = WebClient.builder()
.filter(filterA).filter(filterB).build();
WebClient client2 = client1.mutate()
.filter(filterC).filter(filterD).build();
// client1 has filterA, filterB
// client2 has filterA, filterB, filterC, filterD
val client1 = WebClient.builder()
.filter(filterA).filter(filterB).build()
val client2 = client1.mutate()
.filter(filterC).filter(filterD).build()
// client1 has filterA, filterB
// client2 has filterA, filterB, filterC, filterD
MaxInMemorySize
码具有limits以便将数据缓存在内存中以避免应用程序内存问题。默认值为 256KB。如果该值不足,你将收到以下错误:
org.springframework.core.io.buffer.DataBufferLimitException: Exceeded limit on max bytes to buffer
如需更改默认编解码器的限制,请使用以下方法:
-
Java
-
Kotlin
WebClient webClient = WebClient.builder()
.codecs(configurer -> configurer.defaultCodecs().maxInMemorySize(2 * 1024 * 1024))
.build();
val webClient = WebClient.builder()
.codecs { configurer -> configurer.defaultCodecs().maxInMemorySize(2 * 1024 * 1024) }
.build()
Reactor Netty
若要自定义 Reactor Netty 设置,请提供一个预先配置的 HttpClient
:
-
Java
-
Kotlin
HttpClient httpClient = HttpClient.create().secure(sslSpec -> ...);
WebClient webClient = WebClient.builder()
.clientConnector(new ReactorClientHttpConnector(httpClient))
.build();
val httpClient = HttpClient.create().secure { ... }
val webClient = WebClient.builder()
.clientConnector(ReactorClientHttpConnector(httpClient))
.build()
Resources
默认情况下,HttpClient
参与 reactor.netty.http.HttpResources
中的全局 Reactor Netty 资源,包括事件循环线程和连接池。这是推荐模式,因为固定的共享资源是事件循环并发的首选。在这种模式下,全球资源在进程退出之前保持活动状态。
如果服务器已随进程计时,通常不需要明确关闭。但是,如果服务器可以在进程中启动或停止(例如,作为一个 WAR 部署的 Spring MVC 应用程序),你可以声明一个带有 globalResources=true
(默认)type 的 Spring 管理 bean,以确保在关闭 Spring ApplicationContext
时关闭 Reactor Netty 全局资源,如下例所示:
-
Java
-
Kotlin
@Bean
public ReactorResourceFactory reactorResourceFactory() {
return new ReactorResourceFactory();
}
@Bean
fun reactorResourceFactory() = ReactorResourceFactory()
你也可以选择不参与全局 Reactor Netty 资源。但是,在这种模式下,确保所有 Reactor Netty 客户端和服务器实例使用共享资源的责任在于你,如下例所示:
- Java
-
@Bean public ReactorResourceFactory resourceFactory() { ReactorResourceFactory factory = new ReactorResourceFactory(); factory.setUseGlobalResources(false); (1) return factory; } @Bean public WebClient webClient() { Function<HttpClient, HttpClient> mapper = client -> { // Further customizations... }; ClientHttpConnector connector = new ReactorClientHttpConnector(resourceFactory(), mapper); (2) return WebClient.builder().clientConnector(connector).build(); (3) }
1 | 创建独立于全局资源的资源。 |
2 | 使用带有资源工厂的 ReactorClientHttpConnector 构造函数。 |
3 | 将连接器插入 WebClient.Builder 。
|
4 | 创建独立于全局资源的资源。 |
5 | 使用带有资源工厂的 ReactorClientHttpConnector 构造函数。 |
6 | 将连接器插入 WebClient.Builder 。 |
Timeouts
配置连接超时:
-
Java
-
Kotlin
import io.netty.channel.ChannelOption;
HttpClient httpClient = HttpClient.create()
.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000);
WebClient webClient = WebClient.builder()
.clientConnector(new ReactorClientHttpConnector(httpClient))
.build();
import io.netty.channel.ChannelOption
val httpClient = HttpClient.create()
.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000);
val webClient = WebClient.builder()
.clientConnector(ReactorClientHttpConnector(httpClient))
.build();
配置读超时或写超时:
-
Java
-
Kotlin
import io.netty.handler.timeout.ReadTimeoutHandler;
import io.netty.handler.timeout.WriteTimeoutHandler;
HttpClient httpClient = HttpClient.create()
.doOnConnected(conn -> conn
.addHandlerLast(new ReadTimeoutHandler(10))
.addHandlerLast(new WriteTimeoutHandler(10)));
// Create WebClient...
import io.netty.handler.timeout.ReadTimeoutHandler
import io.netty.handler.timeout.WriteTimeoutHandler
val httpClient = HttpClient.create()
.doOnConnected { conn -> conn
.addHandlerLast(ReadTimeoutHandler(10))
.addHandlerLast(WriteTimeoutHandler(10))
}
// Create WebClient...
配置针对所有请求的响应超时:
-
Java
-
Kotlin
HttpClient httpClient = HttpClient.create()
.responseTimeout(Duration.ofSeconds(2));
// Create WebClient...
val httpClient = HttpClient.create()
.responseTimeout(Duration.ofSeconds(2));
// Create WebClient...
配置针对特定请求的响应超时:
-
Java
-
Kotlin
WebClient.create().get()
.uri("https://example.org/path")
.httpRequest(httpRequest -> {
HttpClientRequest reactorRequest = httpRequest.getNativeRequest();
reactorRequest.responseTimeout(Duration.ofSeconds(2));
})
.retrieve()
.bodyToMono(String.class);
WebClient.create().get()
.uri("https://example.org/path")
.httpRequest { httpRequest: ClientHttpRequest ->
val reactorRequest = httpRequest.getNativeRequest<HttpClientRequest>()
reactorRequest.responseTimeout(Duration.ofSeconds(2))
}
.retrieve()
.bodyToMono(String::class.java)
JDK HttpClient
以下示例显示如何自定义 JDK HttpClient
:
-
Java
-
Kotlin
HttpClient httpClient = HttpClient.newBuilder()
.followRedirects(Redirect.NORMAL)
.connectTimeout(Duration.ofSeconds(20))
.build();
ClientHttpConnector connector =
new JdkClientHttpConnector(httpClient, new DefaultDataBufferFactory());
WebClient webClient = WebClient.builder().clientConnector(connector).build();
val httpClient = HttpClient.newBuilder()
.followRedirects(Redirect.NORMAL)
.connectTimeout(Duration.ofSeconds(20))
.build()
val connector = JdkClientHttpConnector(httpClient, DefaultDataBufferFactory())
val webClient = WebClient.builder().clientConnector(connector).build()
Jetty
以下示例演示了如何自定义 Jetty HttpClient
设置:
-
Java
-
Kotlin
HttpClient httpClient = new HttpClient();
httpClient.setCookieStore(...);
WebClient webClient = WebClient.builder()
.clientConnector(new JettyClientHttpConnector(httpClient))
.build();
val httpClient = HttpClient()
httpClient.cookieStore = ...
val webClient = WebClient.builder()
.clientConnector(JettyClientHttpConnector(httpClient))
.build();
默认情况下,HttpClient
创建自己的资源(Executor
、ByteBufferPool
、Scheduler
),它将在进程退出或调用 stop()
之前保持活动状态。
您可以在 Jetty 客户端(和服务器)的多个实例之间共享资源,并确保在关闭 Spring ApplicationContext
时关闭资源,方法是声明一个类型为 JettyResourceFactory
的 Spring 管理 Bean,如下例所示:
- Java
-
@Bean public JettyResourceFactory resourceFactory() { return new JettyResourceFactory(); } @Bean public WebClient webClient() { HttpClient httpClient = new HttpClient(); // Further customizations... ClientHttpConnector connector = new JettyClientHttpConnector(httpClient, resourceFactory()); 1 return WebClient.builder().clientConnector(connector).build(); 2 }
1 | 使用带有资源工厂的 JettyClientHttpConnector 构造函数。 |
2 | 将连接器插入 WebClient.Builder 。
|
3 | 使用带有资源工厂的 JettyClientHttpConnector 构造函数。 |
4 | 将连接器插入 WebClient.Builder 。 |
HttpComponents
以下示例演示了如何自定义 Apache HttpComponents HttpClient
设置:
-
Java
-
Kotlin
HttpAsyncClientBuilder clientBuilder = HttpAsyncClients.custom();
clientBuilder.setDefaultRequestConfig(...);
CloseableHttpAsyncClient client = clientBuilder.build();
ClientHttpConnector connector = new HttpComponentsClientHttpConnector(client);
WebClient webClient = WebClient.builder().clientConnector(connector).build();
val client = HttpAsyncClients.custom().apply {
setDefaultRequestConfig(...)
}.build()
val connector = HttpComponentsClientHttpConnector(client)
val webClient = WebClient.builder().clientConnector(connector).build()