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# 客户端配置
<a name="client-configuration"></a>

在 1.x 中，已通过在客户端或客户端生成器上设置 `ClientConfiguration` 实例修改了 SDK 客户端配置。在版本 2.x 中，已将客户端配置分为单独的配置类。利用单独的配置类，您可以为异步客户端与同步客户端配置不同的 HTTP 客户端，但仍使用相同的 `ClientOverrideConfiguration` 类。

**Example 版本 1.x 中的客户端配置**  

```
AmazonDynamoDBClientBuilder.standard()
.withClientConfiguration(clientConfiguration)
.build()
```

**Example 版本 2.x 中的同步客户端配置**  

```
ProxyConfiguration.Builder proxyConfig = ProxyConfiguration.builder();

ApacheHttpClient.Builder httpClientBuilder =
        ApacheHttpClient.builder()
                        .proxyConfiguration(proxyConfig.build());

ClientOverrideConfiguration.Builder overrideConfig =
        ClientOverrideConfiguration.builder();

DynamoDbClient client =
        DynamoDbClient.builder()
                      .httpClientBuilder(httpClientBuilder)
                      .overrideConfiguration(overrideConfig.build())
                      .build();
```

**Example 版本 2.x 中的异步客户端配置**  

```
NettyNioAsyncHttpClient.Builder httpClientBuilder =
        NettyNioAsyncHttpClient.builder();

ClientOverrideConfiguration.Builder overrideConfig =
        ClientOverrideConfiguration.builder();

ClientAsyncConfiguration.Builder asyncConfig =
        ClientAsyncConfiguration.builder();

DynamoDbAsyncClient client =
        DynamoDbAsyncClient.builder()
                           .httpClientBuilder(httpClientBuilder)
                           .overrideConfiguration(overrideConfig.build())
                           .asyncConfiguration(asyncConfig.build())
                           .build();
```

## HTTP 客户端
<a name="client-configuration-http"></a>

### 主要更改
<a name="client-configuration-http-notables"></a>
+ 在版本 2.x 中，您可以通过使用 `clientBuilder.httpClientBuilder` 指定实现来更改在运行时使用的 HTTP 客户端。
+ 使用 `clientBuilder.httpClient` 将 HTTP 客户端传递给服务客户端生成器时，如果服务客户端关闭，则默认情况下不会关闭 HTTP 客户端。这让您可以在服务客户端之间共享 HTTP 客户端。
+ 异步 HTTP 客户端现在使用非阻塞 IO。
+ 一些操作现在使用 HTTP/2 来提高性能。

### 更改设置
<a name="client-configuration-http-setting-diffs"></a>


| 设置 | 1.x | 2.x 同步，Apache | 2.x 异步，Netty | 
| --- | --- | --- | --- | 
|  |  <pre>ClientConfiguration clientConfig = <br />    new ClientConfiguration()</pre>  |  <pre>ApacheHttpClient.Builder httpClientBuilder = <br />    ApacheHttpClient.builder()</pre>  |  <pre>NettyNioAsyncHttpClient.Builder httpClientBuilder = <br />    NettyNioAsyncHttpClient.builder()</pre>  | 
| 最大连接数 |  <pre>clientConfig.setMaxConnections(...)<br />clientConfig.withMaxConnections(...)</pre>  |  <pre>httpClientBuilder.maxConnections(...)</pre>  |  <pre>httpClientBuilder.maxConcurrency(...)</pre>  | 
| 连接超时 |  <pre>clientConfig.setConnectionTimeout(...)<br />clientConfig.withConnectionTimeout(...)</pre>  |  <pre>httpClientBuilder.connectionTimeout(...)<br />httpClientBuilder.connectionAcquisitionTimeout(...)</pre>  |  <pre>httpClientBuilder.connectionTimeout(...)</pre>  | 
| 套接字超时 |  <pre>clientConfig.setSocketTimeout(...)<br />clientConfig.withSocketTimeout(...)</pre>  |  <pre>httpClientBuilder.socketTimeout(...)</pre>  |  <pre>httpClientBuilder.writeTimeout(...)<br />httpClientBuilder.readTimeout(...)</pre>  | 
| 连接 TTL |  <pre>clientConfig.setConnectionTTL(...)<br />clientConfig.withConnectionTTL(...)</pre>  |  <pre>httpClientBuilder.connectionTimeToLive(...)</pre>  |  <pre>httpClientBuilder.connectionTimeToLive(...)</pre>  | 
| 连接最大空闲时间 |  <pre>clientConfig.setConnectionMaxIdleMillis(...)<br />clientConfig.withConnectionMaxIdleMillis(...)</pre>  |  <pre>httpClientBuilder.connectionMaxIdleTime(...)</pre>  |  <pre>httpClientBuilder.connectionMaxIdleTime(...)</pre>  | 
| 处于非活动状态后进行验证 |  <pre>clientConfig.setValidateAfterInactivityMillis(...)<br />clientConfig.withValidateAfterInactivityMillis(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 本地地址 |  <pre>clientConfig.setLocalAddress(...)<br />clientConfig.withLocalAddress(...)</pre>  |  <pre>httpClientBuilder.localAddress(...)</pre>  | [不支持](https://github.com/aws/aws-sdk-java-v2/issues/857) | 
| 已启用 Expect-continue |  <pre>clientConfig.setUseExpectContinue(...)<br />clientConfig.withUseExpectContinue(...)</pre>  |  <pre>httpClientBuilder.expectContinueEnabled(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 连接收割者 |  <pre>clientConfig.setUseReaper(...)<br />clientConfig.withReaper(...)</pre>  |  <pre>httpClientBuilder.useIdleConnectionReaper(...)</pre>  |  <pre>httpClientBuilder.useIdleConnectionReaper(...)</pre>  | 
|  |  <pre>AmazonDynamoDBClientBuilder.standard()<br />    .withClientConfiguration(clientConfiguration)<br />    .build()</pre>  |  <pre>DynamoDbClient.builder()<br />    .httpClientBuilder(httpClientBuilder)<br />    .build()</pre>  |  <pre>DynamoDbAsyncClient.builder()<br />.httpClientBuilder(httpClientBuilder)<br />.build()</pre>  | 

## HTTP 客户端代理
<a name="client-configuration-http-proxy"></a>


| 设置 | 1.x | 2.x 同步，Apache | 2.x 异步，Netty | 
| --- | --- | --- | --- | 
|  |  <pre>ClientConfiguration clientConfig =<br />    new ClientConfiguration()</pre>  |  <pre>ProxyConfiguration.Builder proxyConfig =<br />    ProxyConfiguration.builder()</pre>  |  <pre>ProxyConfiguration.Builder proxyConfig =<br />    ProxyConfiguration.builder()</pre>  | 
| 代理主机 |  <pre>clientConfig.setProxyHost(...)<br />clientConfig.withProxyHost(...)</pre>  |  <pre>proxyConfig.endpoint(...)</pre>  |  <pre>proxyConfig.host(...)</pre>  | 
| 代理端口 |  <pre>clientConfig.setProxyPort(...)<br />clientConfig.withProxyPort(...)</pre>  |  <pre>proxyConfig.endpoint(...)</pre> [代理端口](http-configuration-apache.md#http-configuration-apache-proxy-conf-ex)嵌入在 `endpoint`  |  <pre>proxyConfig.port(...)</pre>  | 
| 代理用户名 |  <pre>clientConfig.setProxyUsername(...)<br />clientConfig.withProxyUsername(...)</pre>  |  <pre>proxyConfig.username(...)</pre>  |  <pre>proxyConfig.username(...)</pre>  | 
| 代理密码 |  <pre>clientConfig.setProxyPassword(...)<br />clientConfig.withProxyPassword(...)</pre>  |  <pre>proxyConfig.password(...)</pre>  |  <pre>proxyConfig.password(...)</pre>  | 
| 代理域 |  <pre>clientConfig.setProxyDomain(...)<br />clientConfig.withProxyDomain(...)</pre>  |  <pre>proxyConfig.ntlmDomain(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 代理工作站 |  <pre>clientConfig.setProxyWorkspace(...)<br />clientConfig.withProxyWorkstation(...)</pre>  |  <pre>proxyConfig.ntlmWorkstation(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 代理身份验证方法 |  <pre>clientConfig.setProxyAuthenticationMethods(...)<br />clientConfig.withProxyAuthenticationMethods(...)</pre>  |  [不支持](https://github.com/aws/aws-sdk-java-v2/issues/858)  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 预发式基本代理身份验证 |  <pre>clientConfig.setPreemptiveBasicProxyAuth(...)<br />clientConfig.withPreemptiveBasicProxyAuth(...)</pre>  |  <pre>proxyConfig.preemptiveBasicAuthenticationEnabled(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 非代理主机 |  <pre>clientConfig.setNonProxyHosts(...)<br />clientConfig.withNonProxyHosts(...)</pre>  |  <pre>proxyConfig.nonProxyHosts(...)</pre>  |  <pre>proxyConfig.nonProxyHosts(...)</pre>  | 
| 禁用套接字代理 |  <pre>clientConfig.setDisableSocketProxy(...)<br />clientConfig.withDisableSocketProxy(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
|  |  <pre>AmazonDynamoDBClientBuilder.standard()<br />    .withClientConfiguration(clientConfiguration)<br />    .build()</pre>  |  <pre>httpClientBuilder.proxyConfiguration(<br />    proxyConfig.build())</pre>  |  <pre>httpClientBuilder.proxyConfiguration(<br />    proxyConfig.build())</pre>  | 

## 客户端覆盖
<a name="client-override-config-diffs"></a>


| 设置 | 1.x | 2.x | 
| --- | --- | --- | 
|  |  <pre>ClientConfiguration clientConfig =<br />    new ClientConfiguration()</pre>  |  <pre>ClientOverrideConfiguration.Builder overrideConfig =<br />    ClientOverrideConfiguration.builder()</pre>  | 
| 用户代理前缀 |  <pre>clientConfig.setUserAgentPrefix(...)<br />clientConfig.withUserAgentPrefix(...)</pre>  |  <pre>overrideConfig.advancedOption(<br />    SdkAdvancedClientOption.USER_AGENT_PREFIX, ...)</pre>  | 
| 用户代理后缀 |  <pre>clientConfig.setUserAgentSuffix(...)<br />clientConfig.withUserAgentSuffix(...)</pre>  |  <pre>overrideConfig.advancedOption(<br />    SdkAdvancedClientOption.USER_AGENT_SUFFIX, ...)</pre>  | 
| 签署人 |  <pre>clientConfig.setSignerOverride(...)<br />clientConfig.withSignerOverride(...)</pre>  |  <pre>overrideConfig.advancedOption(<br />    SdkAdvancedClientOption.SIGNER, ...)</pre>  | 
| 其他标头 |  <pre>clientConfig.addHeader(...)<br />clientConfig.withHeader(...)</pre>  |  <pre>overrideConfig.putHeader(...)</pre>  | 
| 请求超时 |  <pre>clientConfig.setRequestTimeout(...)<br />clientConfig.withRequestTimeout(...)</pre>  |  <pre>overrideConfig.apiCallAttemptTimeout(...)</pre>  | 
| 客户端执行超时 |  <pre>clientConfig.setClientExecutionTimeout(...)<br />clientConfig.withClientExecutionTimeout(...)</pre>  |  <pre>overrideConfig.apiCallTimeout(...)</pre>  | 
| 使用 Gzip |  <pre>clientConfig.setUseGzip(...)<br />clientConfig.withGzip(...)</pre>  |  不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)）  | 
| 套接字缓冲区大小提示 |  <pre>clientConfig.setSocketBufferSizeHints(...)<br />clientConfig.withSocketBufferSizeHints(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 缓存响应元数据 |  <pre>clientConfig.setCacheResponseMetadata(...)<br />clientConfig.withCacheResponseMetadata(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| 响应元数据缓存大小 |  <pre>clientConfig.setResponseMetadataCacheSize(...)<br />clientConfig.withResponseMetadataCacheSize(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| DNS 解析程序 |  <pre>clientConfig.setDnsResolver(...)<br />clientConfig.withDnsResolver(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
| TCP keepalive |  <pre>clientConfig.setUseTcpKeepAlive(...)<br />clientConfig.withTcpKeepAlive(...)</pre>  |  此选项现在位于 HTTP 客户端配置中 <pre>- ApacheHttpClient.builder().tcpKeepAlive(true)<br />- NettyNioAsyncHttpClient.builder().tcpKeepAlive(true)</pre>  | 
| 安全随机 |  <pre>clientConfig.setSecureRandom(...)<br />clientConfig.withSecureRandom(...)</pre>  | 不支持（[请求功能](https://github.com/aws/aws-sdk-java-v2/issues/new)） | 
|  |  <pre>AmazonDynamoDBClientBuilder.standard()<br />    .withClientConfiguration(clientConfiguration)<br />    .build()</pre>  |  <pre>DynamoDbClient.builder()<br />    .overrideConfiguration(overrideConfig.build())<br />    .build()</pre>  | 

## 客户端覆盖重试次数
<a name="client-override-retry-config-diffs"></a>


| 设置 | 1.x | 2.x | 
| --- | --- | --- | 
|  |  <pre>ClientConfiguration clientConfig =<br />    new ClientConfiguration()</pre>  |  <pre>ClientOverrideConfiguration.Builder overrideConfigBuilder = <br />    ClientOverrideConfiguration.builder();</pre>  | 
| 最大错误重试数 |  <pre>clientConfig.setMaxErrorRetry(...)<br />clientConfig.withMaxErrorRetry(...)</pre>  |  <pre>// Configure the default retry strategy.<br />overrideConfigBuilder.retryStrategy(b -> b.maxAttempts(...));</pre>  | 
| 使用带节流控制的重试次数 |  <pre>clientConfig.setUseThrottleRetries(...)<br />clientConfig.withUseThrottleRetries(...)</pre>  | [不支持](https://github.com/aws/aws-sdk-java-v2/issues/645) | 
| 节流前的最大连续重试次数 |  <pre>clientConfig.setMaxConsecutiveRetriesBeforeThrottling(...)<br />clientConfig.withMaxConsecutiveRetriesBeforeThrottling(...)</pre>  | [不支持](https://github.com/aws/aws-sdk-java-v2/issues/645) | 
|  |  <pre>AmazonDynamoDBClientBuilder.standard()<br />    .withClientConfiguration(clientConfiguration)<br />    .build()</pre>  |  <pre>DynamoDbClient.builder()<br />        .overrideConfiguration(overrideConfigBuilder.build())<br />        .build();<br /><br />// You also have the option to use a lambda expression to configure and<br />// build the 'ClientOverrideConfiguration.Builder'.<br />DynamoDbClient client = DynamoDbClient.builder()<br />        .overrideConfiguration(o -> o.retryStrategy(b -> b.maxAttempts(5)))<br />        .build();</pre>  | 

## 异步客户端
<a name="client-async-config-diffs"></a>


| 设置 | 1.x | 2.x | 
| --- | --- | --- | 
|  |  |  <pre>ClientAsyncConfiguration.Builder asyncConfig =<br />    ClientAsyncConfiguration.builder()</pre>  | 
| 执行程序 |  <pre>AmazonDynamoDBAsyncClientBuilder.standard()<br />    .withExecutorFactory(...)<br />    .build()</pre>  |  <pre>asyncConfig.advancedOption(<br />    SdkAdvancedAsyncClientOption.FUTURE_COMPLETION_EXECUTOR, ...)</pre>  | 
|  |  |  <pre>DynamoDbAsyncClient.builder()<br />    .asyncConfiguration(asyncConfig)<br />    .build()</pre>  | 

## 其他客户端更改
<a name="client-config-other-diffs"></a>

1.x 中的以下 `ClientConfiguration` 选项在 SDK 的 2.x 中已更改，没有直接等效项。


| 设置 | 1.x | 2.x 等效项 | 
| --- | --- | --- | 
| 协议 |  <pre>clientConfig.setProtocol(Protocol.HTTP)<br />clientConfig.withProtocol(Protocol.HTTP)</pre>  |  默认情况下，协议设置为 HTTPS。要修改设置，请在客户端生成器中指定协议设置为 HTTP 端点： <pre>clientBuilder.endpointOverride(<br />    URI.create("http://..."))</pre>  |