Merge pull request #443 from xbynet/master

解决post/redirect/post 302跳转问题

webmagic-core/src/main/java/us/codecraft/webmagic/downloader/CustomRedirectStrategy.java

+package us.codecraft.webmagic.downloader;
+
+import java.net.URI;
+
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpResponse;
+import org.apache.http.ProtocolException;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.client.methods.HttpRequestWrapper;
+import org.apache.http.client.methods.HttpUriRequest;
+import org.apache.http.impl.client.LaxRedirectStrategy;
+import org.apache.http.protocol.HttpContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ *支持post 302跳转策略实现类
+ *HttpClient默认跳转：httpClientBuilder.setRedirectStrategy(new LaxRedirectStrategy());
+ *上述代码在post/redirect/post这种情况下不会传递原有请求的数据信息。所以参考了下SeimiCrawler这个项目的重定向策略。
+ *原代码地址：https://github.com/zhegexiaohuozi/SeimiCrawler/blob/master/project/src/main/java/cn/wanghaomiao/seimi/http/hc/SeimiRedirectStrategy.java
+ */
+public class CustomRedirectStrategy extends LaxRedirectStrategy {
+    private Logger logger = LoggerFactory.getLogger(getClass());
+
+    @Override
+    public HttpUriRequest getRedirect(HttpRequest request, HttpResponse response, HttpContext context) throws ProtocolException {
+        URI uri = getLocationURI(request, response, context);
+        String method = request.getRequestLine().getMethod();
+        if ("post".equalsIgnoreCase(method)) {
+            try {
+                HttpRequestWrapper httpRequestWrapper = (HttpRequestWrapper) request;
+                httpRequestWrapper.setURI(uri);
+                httpRequestWrapper.removeHeaders("Content-Length");
+                return httpRequestWrapper;
+            } catch (Exception e) {
+                logger.error("强转为HttpRequestWrapper出错");
+            }
+            return new HttpPost(uri);
+        } else {
+            return new HttpGet(uri);
+        }
+    }
+}

webmagic-core/src/main/java/us/codecraft/webmagic/downloader/HttpClientGenerator.java

@@ -89,8 +89,9 @@ public class HttpClientGenerator {
                 }
             });
         }
-
-
+        //解决post/redirect/post 302跳转问题
+        httpClientBuilder.setRedirectStrategy(new CustomRedirectStrategy());
+        
         SocketConfig socketConfig = SocketConfig.custom().setSoTimeout(site.getTimeOut()).setSoKeepAlive(true).setTcpNoDelay(true).build();
         httpClientBuilder.setDefaultSocketConfig(socketConfig);
         connectionManager.setDefaultSocketConfig(socketConfig);