这篇文章主要讲解了“SpringCloud Feign中怎么使用ApacheHttpClient代替默认client方式”，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习“SpringCloud Feign中怎么使用ApacheHttpClient代替默认client方式”吧！
Feign在默认情况下使用的是JDK原生的URLConnection发送HTTP请求，没有连接池，但是对每个地址会保持一个长连接，即利用HTTP的persistence connection。
ApacheHttpClient实现了连接池，同时它封装了访问http的请求头，参数，内容体，响应等等，使客户端发送 HTTP 请求变得容易。
maven 依赖
<dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.5.7</version> </dependency> <dependency> <groupId>io.github.openfeign</groupId> <artifactId>feign-httpclient</artifactId> <version>10.1.0</version> </dependency>
配置文件的修改
feign: httpclient: enabled: true
创建ApacheHttpClient客户端
import javax.net.ssl.SSLContext;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.SSLContexts;
import org.springframework.util.ResourceUtils;
import feign.httpclient.ApacheHttpClient;
@Slf4j
public class FeignClientBuilder {
private boolean enabled;
private String keyPassword;
private String keyStore;
private String keyStorePassword;
private String trustStore;
private String trustStorePassword;
private int maxConnTotal = 2048;
private int maxConnPerRoute = 512;
public FeignClientBuilder(boolean enabled, String keyPassword, String keyStore, String keyStorePassword, String trustStore, String trustStorePassword, int maxConnTotal, int maxConnPerRoute) {
this.enabled = enabled;
this.keyPassword = keyPassword;
this.keyStore = keyStore;
this.keyStorePassword = keyStorePassword;
this.trustStore = trustStore;
this.trustStorePassword = trustStorePassword;
/**
* maxConnTotal是同时间正在使用的最多的连接数
*/
this.maxConnTotal = maxConnTotal;
/**
* maxConnPerRoute是针对一个域名同时间正在使用的最多的连接数
*/
this.maxConnPerRoute = maxConnPerRoute;
}
public ApacheHttpClient apacheHttpClient() {
CloseableHttpClient defaultHttpClient = HttpClients.custom()
.setMaxConnTotal(maxConnTotal)
.setMaxConnPerRoute(maxConnPerRoute)
.build();
ApacheHttpClient defaultApacheHttpClient = new ApacheHttpClient(defaultHttpClient);
if (!enabled) {
return defaultApacheHttpClient;
}
SSLContextBuilder sslContextBuilder = SSLContexts.custom();
// 如果 服务端启用了 TLS 客户端验证，则需要指定 keyStore
if (keyStore == null || keyStore.isEmpty()) {
return new ApacheHttpClient();
} else {
try {
sslContextBuilder
.loadKeyMaterial(
ResourceUtils.getFile(keyStore),
keyStorePassword.toCharArray(),
keyPassword.toCharArray());
} catch (Exception e) {
e.printStackTrace();
}
}
// 如果 https 使用自签名证书，则需要指定 trustStore
if (trustStore == null || trustStore.isEmpty()) {
} else {
try {
sslContextBuilder
// .loadTrustMaterial(TrustAllStrategy.INSTANCE)
.loadTrustMaterial(
ResourceUtils.getFile(trustStore),
trustStorePassword.toCharArray()
);
} catch (Exception e) {
e.printStackTrace();
}
}
try {
SSLContext sslContext = sslContextBuilder.build();
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(
sslContext,
SSLConnectionSocketFactory.getDefaultHostnameVerifier());
CloseableHttpClient httpClient = HttpClients.custom()
.setMaxConnTotal(maxConnTotal)
.setMaxConnPerRoute(maxConnPerRoute)
.setSSLSocketFactory(sslsf)
.build();
ApacheHttpClient apacheHttpClient = new ApacheHttpClient(httpClient);
log.info("feign Client load with ssl.");
return apacheHttpClient;
} catch (Exception e) {
e.printStackTrace();
}
return defaultApacheHttpClient;
}
public static FeignClientBuilderBuilder builder() {
return new FeignClientBuilderBuilder();
}
public static class FeignClientBuilderBuilder {
private boolean enabled;
private String keyPassword;
private String keyStore;
private String keyStorePassword;
private String trustStore;
private String trustStorePassword;
private int maxConnTotal = 2048;
private int maxConnPerRoute = 512;
public FeignClientBuilderBuilder enabled(boolean enabled) {
this.enabled = enabled;
return this;
}
public FeignClientBuilderBuilder keyPassword(String keyPassword) {
this.keyPassword = keyPassword;
return this;
}
public FeignClientBuilderBuilder keyStore(String keyStore) {
this.keyStore = keyStore;
return this;
}
public FeignClientBuilderBuilder keyStorePassword(String keyStorePassword) {
this.keyStorePassword = keyStorePassword;
return this;
}
public FeignClientBuilderBuilder trustStore(String trustStore) {
this.trustStore = trustStore;
return this;
}
public FeignClientBuilderBuilder trustStorePassword(String trustStorePassword) {
this.trustStorePassword = trustStorePassword;
return this;
}
public FeignClientBuilderBuilder maxConnTotal(int maxConnTotal) {
this.maxConnTotal = maxConnTotal;
return this;
}
public FeignClientBuilderBuilder maxConnPerRoute(int maxConnPerRoute) {
this.maxConnPerRoute = maxConnPerRoute;
return this;
}
public FeignClientBuilder build() {
return new FeignClientBuilder(
this.enabled,
this.keyPassword,
this.keyStore,
this.keyStorePassword,
this.trustStore,
this.trustStorePassword,
this.maxConnTotal,
this.maxConnPerRoute
);
}
}
}
使用时可以直接使用builder来创建ApacheHttpClient。
<dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.5.2</version> </dependency>
2017-01-31 19:31:39.057 INFO 3873 --- [askScheduler-13] o.apache.http.impl.execchain.RetryExec : I/O exception (org.apache.http.NoHttpResponseException) caught when processing request to {}->http://192.168.99.100:8080: The target server failed to respond
2017-01-31 19:31:39.058 INFO 3873 --- [askScheduler-13] o.apache.http.impl.execchain.RetryExec : Retrying request to {}->http://192.168.99.100:8080
org/apache/http/impl/execchain/RetryExec.java
/**
* Request executor in the request execution chain that is responsible
* for making a decision whether a request failed due to an I/O error
* should be re-executed.
* <p>
* Further responsibilities such as communication with the opposite
* endpoint is delegated to the next executor in the request execution
* chain.
* </p>
*
* @since 4.3
*/
@Immutable
public class RetryExec implements ClientExecChain {
private final Log log = LogFactory.getLog(getClass());
private final ClientExecChain requestExecutor;
private final HttpRequestRetryHandler retryHandler;
public RetryExec(
final ClientExecChain requestExecutor,
final HttpRequestRetryHandler retryHandler) {
Args.notNull(requestExecutor, "HTTP request executor");
Args.notNull(retryHandler, "HTTP request retry handler");
this.requestExecutor = requestExecutor;
this.retryHandler = retryHandler;
}
@Override
public CloseableHttpResponse execute(
final HttpRoute route,
final HttpRequestWrapper request,
final HttpClientContext context,
final HttpExecutionAware execAware) throws IOException, HttpException {
Args.notNull(route, "HTTP route");
Args.notNull(request, "HTTP request");
Args.notNull(context, "HTTP context");
final Header[] origheaders = request.getAllHeaders();
for (int execCount = 1;; execCount++) {
try {
return this.requestExecutor.execute(route, request, context, execAware);
} catch (final IOException ex) {
if (execAware != null && execAware.isAborted()) {
this.log.debug("Request has been aborted");
throw ex;
}
if (retryHandler.retryRequest(ex, execCount, context)) {
if (this.log.isInfoEnabled()) {
this.log.info("I/O exception ("+ ex.getClass().getName() +
") caught when processing request to "
+ route +
": "
+ ex.getMessage());
}
if (this.log.isDebugEnabled()) {
this.log.debug(ex.getMessage(), ex);
}
if (!RequestEntityProxy.isRepeatable(request)) {
this.log.debug("Cannot retry non-repeatable request");
throw new NonRepeatableRequestException("Cannot retry request " +
"with a non-repeatable request entity", ex);
}
request.setHeaders(origheaders);
if (this.log.isInfoEnabled()) {
this.log.info("Retrying request to " + route);
}
} else {
if (ex instanceof NoHttpResponseException) {
final NoHttpResponseException updatedex = new NoHttpResponseException(
route.getTargetHost().toHostString() + " failed to respond");
updatedex.setStackTrace(ex.getStackTrace());
throw updatedex;
} else {
throw ex;
}
}
}
}
}
}org/apache/http/impl/client/DefaultHttpRequestRetryHandler.java
/**
* The default {@link HttpRequestRetryHandler} used by request executors.
*
* @since 4.0
*/
@Immutable
public class DefaultHttpRequestRetryHandler implements HttpRequestRetryHandler {
public static final DefaultHttpRequestRetryHandler INSTANCE = new DefaultHttpRequestRetryHandler();
/** the number of times a method will be retried */
private final int retryCount;
/** Whether or not methods that have successfully sent their request will be retried */
private final boolean requestSentRetryEnabled;
private final Set<Class<? extends IOException>> nonRetriableClasses;
/**
* Create the request retry handler using the specified IOException classes
*
* @param retryCount how many times to retry; 0 means no retries
* @param requestSentRetryEnabled true if it's OK to retry requests that have been sent
* @param clazzes the IOException types that should not be retried
* @since 4.3
*/
protected DefaultHttpRequestRetryHandler(
final int retryCount,
final boolean requestSentRetryEnabled,
final Collection<Class<? extends IOException>> clazzes) {
super();
this.retryCount = retryCount;
this.requestSentRetryEnabled = requestSentRetryEnabled;
this.nonRetriableClasses = new HashSet<Class<? extends IOException>>();
for (final Class<? extends IOException> clazz: clazzes) {
this.nonRetriableClasses.add(clazz);
}
}
/**
* Create the request retry handler using the following list of
* non-retriable IOException classes: <br>
* <ul>
* <li>InterruptedIOException</li>
* <li>UnknownHostException</li>
* <li>ConnectException</li>
* <li>SSLException</li>
* </ul>
* @param retryCount how many times to retry; 0 means no retries
* @param requestSentRetryEnabled true if it's OK to retry non-idempotent requests that have been sent
*/
@SuppressWarnings("unchecked")
public DefaultHttpRequestRetryHandler(final int retryCount, final boolean requestSentRetryEnabled) {
this(retryCount, requestSentRetryEnabled, Arrays.asList(
InterruptedIOException.class,
UnknownHostException.class,
ConnectException.class,
SSLException.class));
}
/**
* Create the request retry handler with a retry count of 3, requestSentRetryEnabled false
* and using the following list of non-retriable IOException classes: <br>
* <ul>
* <li>InterruptedIOException</li>
* <li>UnknownHostException</li>
* <li>ConnectException</li>
* <li>SSLException</li>
* </ul>
*/
public DefaultHttpRequestRetryHandler() {
this(3, false);
}
/**
* Used {@code retryCount} and {@code requestSentRetryEnabled} to determine
* if the given method should be retried.
*/
@Override
public boolean retryRequest(
final IOException exception,
final int executionCount,
final HttpContext context) {
Args.notNull(exception, "Exception parameter");
Args.notNull(context, "HTTP context");
if (executionCount > this.retryCount) {
// Do not retry if over max retry count
return false;
}
if (this.nonRetriableClasses.contains(exception.getClass())) {
return false;
} else {
for (final Class<? extends IOException> rejectException : this.nonRetriableClasses) {
if (rejectException.isInstance(exception)) {
return false;
}
}
}
final HttpClientContext clientContext = HttpClientContext.adapt(context);
final HttpRequest request = clientContext.getRequest();
if(requestIsAborted(request)){
return false;
}
if (handleAsIdempotent(request)) {
// Retry if the request is considered idempotent
return true;
}
if (!clientContext.isRequestSent() || this.requestSentRetryEnabled) {
// Retry if the request has not been sent fully or
// if it's OK to retry methods that have been sent
return true;
}
// otherwise do not retry
return false;
}
/**
* @return {@code true} if this handler will retry methods that have
* successfully sent their request, {@code false} otherwise
*/
public boolean isRequestSentRetryEnabled() {
return requestSentRetryEnabled;
}
/**
* @return the maximum number of times a method will be retried
*/
public int getRetryCount() {
return retryCount;
}
/**
* @since 4.2
*/
protected boolean handleAsIdempotent(final HttpRequest request) {
return !(request instanceof HttpEntityEnclosingRequest);
}
/**
* @since 4.2
*
* @deprecated (4.3)
*/
@Deprecated
protected boolean requestIsAborted(final HttpRequest request) {
HttpRequest req = request;
if (request instanceof RequestWrapper) { // does not forward request to original
req = ((RequestWrapper) request).getOriginal();
}
return (req instanceof HttpUriRequest && ((HttpUriRequest)req).isAborted());
}
}默认重试3次，三次都失败则抛出NoHttpResponseException或其他异常
感谢各位的阅读，以上就是“SpringCloud Feign中怎么使用ApacheHttpClient代替默认client方式”的内容了，经过本文的学习后，相信大家对SpringCloud Feign中怎么使用ApacheHttpClient代替默认client方式这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是亿速云，小编将为大家推送更多相关知识点的文章，欢迎关注！
免责声明：本站发布的内容（图片、视频和文字）以原创、转载和分享为主，文章观点不代表本网站立场，如果涉及侵权请联系站长邮箱：is@yisu.com进行举报，并提供相关证据，一经查实，将立刻删除涉嫌侵权内容。
