YARN-3147. Clean up RM web proxy code. Contributed by Steve Loughran

(cherry picked from commit 83be450acc)

hadoop-yarn-project/CHANGES.txt

@@ -238,6 +238,8 @@ Release 2.7.0 - UNRELEASED
     YARN-3157. Refactor the exception handling in ConverterUtils#to*Id.
     (Bibin A Chundatt via ozawa)
 
+    YARN-3147. Clean up RM web proxy code. (Steve Loughran via xgong)
+
   OPTIMIZATIONS
 
     YARN-2990. FairScheduler's delay-scheduling always waits for node-local and 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUriUtils.java

@@ -18,11 +18,10 @@
 
 package org.apache.hadoop.yarn.server.webproxy;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.http.HttpConfig;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.util.TrackingUriPlugin;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.UnsupportedEncodingException;
 import java.net.URI;
@@ -34,7 +33,8 @@ import static org.apache.hadoop.yarn.util.StringHelper.ujoin;
 
 public class ProxyUriUtils {
   @SuppressWarnings("unused")
-  private static final Log LOG = LogFactory.getLog(ProxyUriUtils.class);
+  private static final Logger LOG = LoggerFactory.getLogger(
+      ProxyUriUtils.class);
 
   /**Name of the servlet to use when registering the proxy servlet. */
   public static final String PROXY_SERVLET_NAME = "proxy";
@@ -194,4 +194,5 @@ public class ProxyUriUtils {
       return "";
     }
   }
+
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/ProxyUtils.java

@@ -0,0 +1,127 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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
+ *
+ *     http://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.apache.hadoop.yarn.server.webproxy;
+
+import org.apache.hadoop.yarn.webapp.MimeType;
+import org.apache.hadoop.yarn.webapp.hamlet.Hamlet;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.EnumSet;
+
+/**
+ * Class containing general purpose proxy utilities
+ */
+public class ProxyUtils {
+  private static final Logger LOG = LoggerFactory.getLogger(
+      ProxyUtils.class);
+  public static final String E_HTTP_HTTPS_ONLY =
+      "This filter only works for HTTP/HTTPS";
+  public static final String LOCATION = "Location";
+
+  public static class _ implements Hamlet._ {
+    //Empty
+  }
+
+  public static class Page extends Hamlet {
+    Page(PrintWriter out) {
+      super(out, 0, false);
+    }
+
+    public HTML<ProxyUtils._> html() {
+      return new HTML<>("html", null, EnumSet.of(EOpt.ENDTAG));
+    }
+  }
+  
+  /**
+   * Handle redirects with a status code that can in future support verbs other
+   * than GET, thus supporting full REST functionality.
+   * <p>
+   * The target URL is included in the redirect text returned
+   * <p>
+   * At the end of this method, the output stream is closed.
+   * 
+   * @param request request (hence: the verb and any other information
+   * relevant to a redirect)
+   * @param response the response
+   * @param target the target URL -unencoded
+   *
+   */
+  public static void sendRedirect(HttpServletRequest request,
+      HttpServletResponse response,
+      String target)
+      throws IOException {
+    if (LOG.isDebugEnabled()) {
+      LOG.debug("Redirecting {} {} to {}",
+          request.getMethod(), 
+          request.getRequestURI(),
+          target);
+    }
+    String location = response.encodeRedirectURL(target);
+    response.setStatus(HttpServletResponse.SC_FOUND);
+    response.setHeader(LOCATION, location);
+    response.setContentType(MimeType.HTML);
+    PrintWriter writer = response.getWriter();
+    Page p = new Page(writer);
+    p.html()
+        .head().title("Moved")._()
+        .body()
+        .h1("Moved")
+        .div()
+          ._("Content has moved ")
+          .a(location, "here")._()
+        ._()._();
+    writer.close();
+  }
+
+
+  /**
+   * Output 404 with appropriate message.
+   * @param resp the http response.
+   * @param message the message to include on the page.
+   * @throws IOException on any error.
+   */
+  public static void notFound(HttpServletResponse resp, String message)
+      throws IOException {
+    resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
+    resp.setContentType(MimeType.HTML);
+    Page p = new Page(resp.getWriter());
+    p.html().
+        h1(message).
+         _();
+  }
+
+  /**
+   * Reject any request that isn't from an HTTP servlet
+   * @param req request
+   * @throws ServletException if the request is of the wrong type
+   */
+  public static void rejectNonHttpRequests(ServletRequest req) throws
+      ServletException {
+    if (!(req instanceof HttpServletRequest)) {
+      throw new ServletException(E_HTTP_HTTPS_ONLY);
+    }
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/WebAppProxy.java

@@ -21,8 +21,6 @@ package org.apache.hadoop.yarn.server.webproxy;
 import java.io.IOException;
 import java.net.URI;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.http.HttpServer2;
 import org.apache.hadoop.security.authorize.AccessControlList;
@@ -34,12 +32,15 @@ import org.apache.hadoop.yarn.webapp.util.WebAppUtils;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
 
 import com.google.common.annotations.VisibleForTesting;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class WebAppProxy extends AbstractService {
   public static final String FETCHER_ATTRIBUTE= "AppUrlFetcher";
   public static final String IS_SECURITY_ENABLED_ATTRIBUTE = "IsSecurityEnabled";
   public static final String PROXY_HOST_ATTRIBUTE = "proxyHost";
-  private static final Log LOG = LogFactory.getLog(WebAppProxy.class);
+  private static final Logger LOG = LoggerFactory.getLogger(
+      WebAppProxy.class);
   
   private HttpServer2 proxyServer = null;
   private String bindAddress = null;
@@ -109,8 +110,8 @@ public class WebAppProxy extends AbstractService {
       proxyServer.setAttribute(PROXY_HOST_ATTRIBUTE, proxyHost);
       proxyServer.start();
     } catch (IOException e) {
-      LOG.fatal("Could not start proxy web server",e);
+      LOG.error("Could not start proxy web server",e);
-      throw new YarnRuntimeException("Could not start proxy web server",e);
+      throw e;
     }
     super.serviceStart();
   }
@@ -121,7 +122,7 @@ public class WebAppProxy extends AbstractService {
       try {
         proxyServer.stop();
       } catch (Exception e) {
-        LOG.fatal("Error stopping proxy web server", e);
+        LOG.error("Error stopping proxy web server", e);
         throw new YarnRuntimeException("Error stopping proxy web server",e);
       }
     }
@@ -136,6 +137,7 @@ public class WebAppProxy extends AbstractService {
       try {
         proxyServer.join();
       } catch (InterruptedException e) {
+        // ignored
       }
     }
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/WebAppProxyServer.java

@@ -21,16 +21,16 @@ package org.apache.hadoop.yarn.server.webproxy;
 import java.io.IOException;
 import java.net.InetSocketAddress;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.security.SecurityUtil;
 import org.apache.hadoop.service.CompositeService;
+import org.apache.hadoop.util.ExitUtil;
 import org.apache.hadoop.util.ShutdownHookManager;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.yarn.YarnUncaughtExceptionHandler;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
-import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * ProxyServer will sit in between the end user and AppMaster
@@ -43,7 +43,8 @@ public class WebAppProxyServer extends CompositeService {
    */
   public static final int SHUTDOWN_HOOK_PRIORITY = 30;
 
-  private static final Log LOG = LogFactory.getLog(WebAppProxyServer.class);
+  private static final Logger LOG = LoggerFactory.getLogger(
+      WebAppProxyServer.class);
 
   private WebAppProxy proxy = null;
   
@@ -54,11 +55,7 @@ public class WebAppProxyServer extends CompositeService {
   @Override
   protected void serviceInit(Configuration conf) throws Exception {
     Configuration config = new YarnConfiguration(conf);
-    try {
     doSecureLogin(conf);      
-    } catch(IOException ie) {
-      throw new YarnRuntimeException("Proxy Server Failed to login", ie);
-    }
     proxy = new WebAppProxy();
     addService(proxy);
     super.serviceInit(config);
@@ -95,8 +92,7 @@ public class WebAppProxyServer extends CompositeService {
       WebAppProxyServer proxyServer = startServer(configuration);
       proxyServer.proxy.join();
     } catch (Throwable t) {
-      LOG.fatal("Error starting Proxy server", t);
+      ExitUtil.terminate(-1, t);
-      System.exit(-1);
     }
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/WebAppProxyServlet.java

@@ -32,6 +32,7 @@ import java.util.EnumSet;
 import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServlet;
@@ -45,8 +46,6 @@ import org.apache.commons.httpclient.HttpMethod;
 import org.apache.commons.httpclient.cookie.CookiePolicy;
 import org.apache.commons.httpclient.methods.GetMethod;
 import org.apache.commons.httpclient.params.HttpClientParams;
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ApplicationReport;
@@ -59,13 +58,20 @@ import org.apache.hadoop.yarn.util.TrackingUriPlugin;
 import org.apache.hadoop.yarn.webapp.MimeType;
 import org.apache.hadoop.yarn.webapp.hamlet.Hamlet;
 import org.apache.hadoop.yarn.webapp.util.WebAppUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class WebAppProxyServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;
-  private static final Log LOG = LogFactory.getLog(WebAppProxyServlet.class);
+  private static final Logger LOG = LoggerFactory.getLogger(
-  private static final HashSet<String> passThroughHeaders = 
+      WebAppProxyServlet.class);
-    new HashSet<String>(Arrays.asList("User-Agent", "Accept", "Accept-Encoding",
+  private static final Set<String> passThroughHeaders = 
-        "Accept-Language", "Accept-Charset"));
+    new HashSet<>(Arrays.asList(
+        "User-Agent",
+        "Accept",
+        "Accept-Encoding",
+        "Accept-Language",
+        "Accept-Charset"));
   
   public static final String PROXY_USER_COOKIE_NAME = "proxy-user";
 
@@ -83,15 +89,14 @@ public class WebAppProxyServlet extends HttpServlet {
     }
   
     public HTML<WebAppProxyServlet._> html() {
-      return new HTML<WebAppProxyServlet._>("html", null, EnumSet.of(EOpt.ENDTAG));
+      return new HTML<>("html", null, EnumSet.of(EOpt.ENDTAG));
     }
   }
 
   /**
    * Default constructor
    */
-  public WebAppProxyServlet()
+  public WebAppProxyServlet() {
-  {
     super();
     conf = new YarnConfiguration();
     this.trackingUriPlugins =
@@ -109,12 +114,7 @@ public class WebAppProxyServlet extends HttpServlet {
    */
   private static void notFound(HttpServletResponse resp, String message) 
     throws IOException {
-    resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
+    ProxyUtils.notFound(resp, message);
-    resp.setContentType(MimeType.HTML);
-    Page p = new Page(resp.getWriter());
-    p.html().
-      h1(message).
-    _();
   }
   
   /**
@@ -133,7 +133,8 @@ public class WebAppProxyServlet extends HttpServlet {
     resp.setContentType(MimeType.HTML);
     Page p = new Page(resp.getWriter());
     p.html().
-      h1("WARNING: The following page may not be safe!").h3().
+      h1("WARNING: The following page may not be safe!").
+      h3().
       _("click ").a(link, "here").
       _(" to continue to an Application Master web interface owned by ", user).
       _().
@@ -163,7 +164,7 @@ public class WebAppProxyServlet extends HttpServlet {
     HostConfiguration config = new HostConfiguration();
     InetAddress localAddress = InetAddress.getByName(proxyHost);
     if (LOG.isDebugEnabled()) {
-      LOG.debug("local InetAddress for proxy host: " + localAddress.toString());
+      LOG.debug("local InetAddress for proxy host: {}", localAddress);
     }
     config.setLocalAddress(localAddress);
     HttpMethod method = new GetMethod(uri.getEscapedURI());
@@ -174,15 +175,17 @@ public class WebAppProxyServlet extends HttpServlet {
       String name = names.nextElement();
       if(passThroughHeaders.contains(name)) {
         String value = req.getHeader(name);
-        LOG.debug("REQ HEADER: "+name+" : "+value);
+        if (LOG.isDebugEnabled()) {
+          LOG.debug("REQ HEADER: {} : {}", name, value);
+        }
         method.setRequestHeader(name, value);
       }
     }
 
     String user = req.getRemoteUser();
-    if(user != null && !user.isEmpty()) {
+    if (user != null && !user.isEmpty()) {
-      method.setRequestHeader("Cookie",PROXY_USER_COOKIE_NAME+"="+
+      method.setRequestHeader("Cookie",
-          URLEncoder.encode(user, "ASCII"));
+          PROXY_USER_COOKIE_NAME + "=" + URLEncoder.encode(user, "ASCII"));
     }
     OutputStream out = resp.getOutputStream();
     try {
@@ -190,11 +193,11 @@ public class WebAppProxyServlet extends HttpServlet {
       for(Header header : method.getResponseHeaders()) {
         resp.setHeader(header.getName(), header.getValue());
       }
-      if(c != null) {
+      if (c != null) {
         resp.addCookie(c);
       }
       InputStream in = method.getResponseBodyAsStream();
-      if(in != null) {
+      if (in != null) {
         IOUtils.copyBytes(in, out, 4096, true);
       }
     } finally {
@@ -216,8 +219,7 @@ public class WebAppProxyServlet extends HttpServlet {
   private boolean isSecurityEnabled() {
     Boolean b = (Boolean) getServletContext()
         .getAttribute(WebAppProxy.IS_SECURITY_ENABLED_ATTRIBUTE);
-    if(b != null) return b;
+    return b != null ? b : false;
-    return false;
   }
   
   private ApplicationReport getApplicationReport(ApplicationId id)
@@ -238,15 +240,14 @@ public class WebAppProxyServlet extends HttpServlet {
       String userApprovedParamS = 
         req.getParameter(ProxyUriUtils.PROXY_APPROVAL_PARAM);
       boolean userWasWarned = false;
-      boolean userApproved = 
+      boolean userApproved = Boolean.valueOf(userApprovedParamS);
-        (userApprovedParamS != null && Boolean.valueOf(userApprovedParamS));
       boolean securityEnabled = isSecurityEnabled();
       final String remoteUser = req.getRemoteUser();
       final String pathInfo = req.getPathInfo();
 
-      String parts[] = pathInfo.split("/", 3);
+      String[] parts = pathInfo.split("/", 3);
       if(parts.length < 2) {
-        LOG.warn(remoteUser+" Gave an invalid proxy path "+pathInfo);
+        LOG.warn("{} gave an invalid proxy path {}", remoteUser,  pathInfo);
         notFound(resp, "Your path appears to be formatted incorrectly.");
         return;
       }
@@ -255,9 +256,9 @@ public class WebAppProxyServlet extends HttpServlet {
       String rest = parts.length > 2 ? parts[2] : "";
       ApplicationId id = Apps.toAppID(appId);
       if(id == null) {
-        LOG.warn(req.getRemoteUser()+" Attempting to access "+appId+
+        LOG.warn("{} attempting to access {} that is invalid",
-        " that is invalid");
+            remoteUser, appId);
-        notFound(resp, appId+" appears to be formatted incorrectly.");
+        notFound(resp, appId + " appears to be formatted incorrectly.");
         return;
       }
       
@@ -277,35 +278,34 @@ public class WebAppProxyServlet extends HttpServlet {
       
       boolean checkUser = securityEnabled && (!userWasWarned || !userApproved);
 
-      ApplicationReport applicationReport = null;
+      ApplicationReport applicationReport;
       try {
         applicationReport = getApplicationReport(id);
       } catch (ApplicationNotFoundException e) {
         applicationReport = null;
       }
       if(applicationReport == null) {
-        LOG.warn(req.getRemoteUser()+" Attempting to access "+id+
+        LOG.warn("{} attempting to access {} that was not found",
-            " that was not found");
+            remoteUser, id);
 
         URI toFetch =
             ProxyUriUtils
                 .getUriFromTrackingPlugins(id, this.trackingUriPlugins);
-        if (toFetch != null)
+        if (toFetch != null) {
-        {
+          ProxyUtils.sendRedirect(req, resp, toFetch.toString());
-          resp.sendRedirect(resp.encodeRedirectURL(toFetch.toString()));
           return;
         }
 
-        notFound(resp, "Application "+appId+" could not be found, " +
+        notFound(resp, "Application " + appId + " could not be found, " +
                        "please try the history server");
         return;
       }
       String original = applicationReport.getOriginalTrackingUrl();
-      URI trackingUri = null;
+      URI trackingUri;
       // fallback to ResourceManager's app page if no tracking URI provided
       if(original == null || original.equals("N/A")) {
-        resp.sendRedirect(resp.encodeRedirectURL(
+        ProxyUtils.sendRedirect(req, resp, 
-            StringHelper.pjoin(rmAppPageUrlBase, id.toString())));
+            StringHelper.pjoin(rmAppPageUrlBase, id.toString()));
         return;
       } else {
         if (ProxyUriUtils.getSchemeFromUrl(original).isEmpty()) {
@@ -318,8 +318,9 @@ public class WebAppProxyServlet extends HttpServlet {
 
       String runningUser = applicationReport.getUser();
       if(checkUser && !runningUser.equals(remoteUser)) {
-        LOG.info("Asking "+remoteUser+" if they want to connect to the " +
+        LOG.info("Asking {} if they want to connect to the "
-            "app master GUI of "+appId+" owned by "+runningUser);
+            + "app master GUI of {} owned by {}",
+            remoteUser, appId, runningUser);
         warnUserPage(resp, ProxyUriUtils.getPathAndQuery(id, rest, 
             req.getQueryString(), true), runningUser, id);
         return;
@@ -329,29 +330,45 @@ public class WebAppProxyServlet extends HttpServlet {
           StringHelper.ujoin(trackingUri.getPath(), rest), req.getQueryString(),
           null);
       
-      LOG.info(req.getRemoteUser()+" is accessing unchecked "+toFetch+
+      LOG.info("{} is accessing unchecked {}"
-          " which is the app master GUI of "+appId+" owned by "+runningUser);
+          + " which is the app master GUI of {} owned by {}",
+          remoteUser, toFetch, appId, runningUser);
 
-      switch(applicationReport.getYarnApplicationState()) {
+      switch (applicationReport.getYarnApplicationState()) {
         case KILLED:
         case FINISHED:
         case FAILED:
-        resp.sendRedirect(resp.encodeRedirectURL(toFetch.toString()));
+          ProxyUtils.sendRedirect(req, resp, toFetch.toString());
           return;
+        default:
+          // fall out of the switch
       }
       Cookie c = null;
-      if(userWasWarned && userApproved) {
+      if (userWasWarned && userApproved) {
         c = makeCheckCookie(id, true);
       }
       proxyLink(req, resp, toFetch, c, getProxyHost());
 
-    } catch(URISyntaxException e) {
+    } catch(URISyntaxException | YarnException e) {
-      throw new IOException(e); 
-    } catch (YarnException e) {
       throw new IOException(e); 
     }
   }
 
+  /**
+   * This method is used by Java object deserialization, to fill in the
+   * transient {@link #trackingUriPlugins} field.
+   * See {@link ObjectInputStream#defaultReadObject()}
+   * <p>
+   *   <I>Do not remove</I>
+   * <p>
+   * Yarn isn't currently serializing this class, but findbugs
+   * complains in its absence.
+   * 
+   * 
+   * @param input source
+   * @throws IOException IO failure
+   * @throws ClassNotFoundException classloader fun
+   */
   private void readObject(ObjectInputStream input)
       throws IOException, ClassNotFoundException {
     input.defaultReadObject();

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmFilterInitializer.java

@@ -36,7 +36,7 @@ public class AmFilterInitializer extends FilterInitializer {
   
   @Override
   public void initFilter(FilterContainer container, Configuration conf) {
-    Map<String, String> params = new HashMap<String, String>();
+    Map<String, String> params = new HashMap<>();
     List<String> proxies = WebAppUtils.getProxyHostsAndPortsForAmFilter(conf);
     StringBuilder sb = new StringBuilder();
     for (String proxy : proxies) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/amfilter/AmIpFilter.java

@@ -38,26 +38,27 @@ import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience.Public;
 import org.apache.hadoop.yarn.conf.HAUtil;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.webproxy.ProxyUtils;
 import org.apache.hadoop.yarn.server.webproxy.WebAppProxyServlet;
 import org.apache.hadoop.yarn.util.RMHAUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 @Public
 public class AmIpFilter implements Filter {
-  private static final Log LOG = LogFactory.getLog(AmIpFilter.class);
+  private static final Logger LOG = LoggerFactory.getLogger(AmIpFilter.class);
   
   @Deprecated
   public static final String PROXY_HOST = "PROXY_HOST";
   @Deprecated
   public static final String PROXY_URI_BASE = "PROXY_URI_BASE";
-  static final String PROXY_HOSTS = "PROXY_HOSTS";
+  public static final String PROXY_HOSTS = "PROXY_HOSTS";
-  static final String PROXY_HOSTS_DELIMITER = ",";
+  public static final String PROXY_HOSTS_DELIMITER = ",";
-  static final String PROXY_URI_BASES = "PROXY_URI_BASES";
+  public static final String PROXY_URI_BASES = "PROXY_URI_BASES";
-  static final String PROXY_URI_BASES_DELIMITER = ",";
+  public static final String PROXY_URI_BASES_DELIMITER = ",";
   //update the proxy IP list about every 5 min
   private static final long updateInterval = 5 * 60 * 1000;
 
@@ -72,7 +73,7 @@ public class AmIpFilter implements Filter {
     if (conf.getInitParameter(PROXY_HOST) != null
         && conf.getInitParameter(PROXY_URI_BASE) != null) {
       proxyHosts = new String[]{conf.getInitParameter(PROXY_HOST)};
-      proxyUriBases = new HashMap<String, String>(1);
+      proxyUriBases = new HashMap<>(1);
       proxyUriBases.put("dummy", conf.getInitParameter(PROXY_URI_BASE));
     } else {
       proxyHosts = conf.getInitParameter(PROXY_HOSTS)
@@ -80,13 +81,13 @@ public class AmIpFilter implements Filter {
 
       String[] proxyUriBasesArr = conf.getInitParameter(PROXY_URI_BASES)
           .split(PROXY_URI_BASES_DELIMITER);
-      proxyUriBases = new HashMap<String, String>();
+      proxyUriBases = new HashMap<>(proxyUriBasesArr.length);
       for (String proxyUriBase : proxyUriBasesArr) {
         try {
           URL url = new URL(proxyUriBase);
           proxyUriBases.put(url.getHost() + ":" + url.getPort(), proxyUriBase);
         } catch(MalformedURLException e) {
-          LOG.warn(proxyUriBase + " does not appear to be a valid URL", e);
+          LOG.warn("{} does not appear to be a valid URL", proxyUriBase, e);
         }
       }
     }
@@ -96,18 +97,18 @@ public class AmIpFilter implements Filter {
     long now = System.currentTimeMillis();
     synchronized(this) {
       if(proxyAddresses == null || (lastUpdate + updateInterval) >= now) {
-        proxyAddresses = new HashSet<String>();
+        proxyAddresses = new HashSet<>();
         for (String proxyHost : proxyHosts) {
           try {
               for(InetAddress add : InetAddress.getAllByName(proxyHost)) {
                 if (LOG.isDebugEnabled()) {
-                  LOG.debug("proxy address is: " + add.getHostAddress());
+                  LOG.debug("proxy address is: {}", add.getHostAddress());
                 }
                 proxyAddresses.add(add.getHostAddress());
               }
               lastUpdate = now;
             } catch (UnknownHostException e) {
-              LOG.warn("Could not locate " + proxyHost + " - skipping", e);
+              LOG.warn("Could not locate {} - skipping", proxyHost, e);
             }
           }
         if (proxyAddresses.isEmpty()) {
@@ -126,20 +127,17 @@ public class AmIpFilter implements Filter {
   @Override
   public void doFilter(ServletRequest req, ServletResponse resp,
       FilterChain chain) throws IOException, ServletException {
-    if(!(req instanceof HttpServletRequest)) {
+    ProxyUtils.rejectNonHttpRequests(req);
-      throw new ServletException("This filter only works for HTTP/HTTPS");
-    }
 
     HttpServletRequest httpReq = (HttpServletRequest)req;
     HttpServletResponse httpResp = (HttpServletResponse)resp;
     if (LOG.isDebugEnabled()) {
-      LOG.debug("Remote address for request is: " + httpReq.getRemoteAddr());
+      LOG.debug("Remote address for request is: {}", httpReq.getRemoteAddr());
     }
-    if(!getProxyAddresses().contains(httpReq.getRemoteAddr())) {
+    if (!getProxyAddresses().contains(httpReq.getRemoteAddr())) {
       String redirectUrl = findRedirectUrl();
-      redirectUrl = httpResp.encodeRedirectURL(redirectUrl +
+      String target = redirectUrl + httpReq.getRequestURI();
-          httpReq.getRequestURI());
+      ProxyUtils.sendRedirect(httpReq,  httpResp,  target);
-      httpResp.sendRedirect(redirectUrl);
       return;
     }
 
@@ -153,9 +151,9 @@ public class AmIpFilter implements Filter {
         }
       }
     }
-    if(user == null) {
+    if (user == null) {
-      LOG.warn("Could not find "+WebAppProxyServlet.PROXY_USER_COOKIE_NAME
+      LOG.warn("Could not find " + WebAppProxyServlet.PROXY_USER_COOKIE_NAME
-          +" cookie, so user will not be set");
+               + " cookie, so user will not be set");
       chain.doFilter(req, resp);
     } else {
       final AmIpPrincipal principal = new AmIpPrincipal(user);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/test/java/org/apache/hadoop/yarn/server/webproxy/TestWebAppProxyServlet.java

@@ -39,8 +39,6 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
 import org.apache.hadoop.http.HttpServer2;
@@ -54,7 +52,6 @@ import org.apache.hadoop.yarn.api.records.impl.pb.ApplicationReportPBImpl;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.ApplicationNotFoundException;
 import org.apache.hadoop.yarn.exceptions.YarnException;
-import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
 import org.apache.hadoop.yarn.webapp.util.WebAppUtils;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
@@ -62,15 +59,16 @@ import org.junit.Test;
 import org.mortbay.jetty.Server;
 import org.mortbay.jetty.servlet.Context;
 import org.mortbay.jetty.servlet.ServletHolder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Test the WebAppProxyServlet and WebAppProxy. For back end use simple web
  * server.
  */
 public class TestWebAppProxyServlet {
-
+  private static final Logger LOG = LoggerFactory.getLogger(
-  private static final Log LOG = LogFactory
+      TestWebAppProxyServlet.class);
-      .getLog(TestWebAppProxyServlet.class);
 
   private static Server server;
   private static int originalPort = 0;
@@ -273,11 +271,10 @@ public class TestWebAppProxyServlet {
     }
 
     @Override
-    public synchronized void init(Configuration conf) {
+    public synchronized void serviceInit(Configuration conf) throws Exception {
-      Configuration config = new YarnConfiguration(conf);
       proxy = new WebAppProxyForTest();
       addService(proxy);
-      super.init(config);
+      super.serviceInit(conf);
     }
 
   }
@@ -288,8 +285,7 @@ public class TestWebAppProxyServlet {
     AppReportFetcherForTest appReportFetcher;
 
     @Override
-    public void start() {
+    protected void serviceStart() throws Exception {
-      try {
       Configuration conf = getConfig();
       String bindAddress = conf.get(YarnConfiguration.PROXY_ADDRESS);
       bindAddress = StringUtils.split(bindAddress, ':')[0];
@@ -318,12 +314,8 @@ public class TestWebAppProxyServlet {
       
       proxyServer.setAttribute(PROXY_HOST_ATTRIBUTE, proxyHost);
       proxyServer.start();
-        System.out.println("Proxy server is started at port " + 
+      LOG.info("Proxy server is started at port {}",
           proxyServer.getConnectorAddress(0).getPort());
-      } catch (Exception e) {
-        LOG.fatal("Could not start proxy web server", e);
-        throw new YarnRuntimeException("Could not start proxy web server", e);
-      }
     }
 
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/test/java/org/apache/hadoop/yarn/server/webproxy/amfilter/TestAmFilter.java

@@ -19,6 +19,8 @@
 package org.apache.hadoop.yarn.server.webproxy.amfilter;
 
 import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.util.*;
 import java.util.concurrent.atomic.AtomicBoolean;
 
@@ -29,6 +31,7 @@ import javax.servlet.http.HttpServletResponse;
 
 import static org.junit.Assert.*;
 
+import org.apache.hadoop.yarn.server.webproxy.ProxyUtils;
 import org.apache.hadoop.yarn.server.webproxy.WebAppProxyServlet;
 import org.glassfish.grizzly.servlet.HttpServletResponseImpl;
 import org.junit.Test;
@@ -151,7 +154,7 @@ public class TestAmFilter {
       testFilter.doFilter(failRequest, response, chain);
       fail();
     } catch (ServletException e) {
-      assertEquals("This filter only works for HTTP/HTTPS", e.getMessage());
+      assertEquals(ProxyUtils.E_HTTP_HTTPS_ONLY, e.getMessage());
     }
 
     // request with HttpServletRequest
@@ -160,7 +163,9 @@ public class TestAmFilter {
     Mockito.when(request.getRequestURI()).thenReturn("/redirect");
     testFilter.doFilter(request, response, chain);
     // address "redirect" is not in host list
-    assertEquals("http://bogus/redirect", response.getRedirect());
+    assertEquals(302, response.status);
+    String redirect = response.getHeader(ProxyUtils.LOCATION);
+    assertEquals("http://bogus/redirect", redirect);
     // "127.0.0.1" contains in host list. Without cookie
     Mockito.when(request.getRemoteAddr()).thenReturn("127.0.0.1");
     testFilter.doFilter(request, response, chain);
@@ -186,6 +191,11 @@ public class TestAmFilter {
 
   private class HttpServletResponseForTest extends HttpServletResponseImpl {
     String redirectLocation = "";
+    int status;
+    private String contentType;
+    private final Map<String, String> headers = new HashMap<>(1);
+    private StringWriter body;
+
 
     public String getRedirect() {
       return redirectLocation;
@@ -201,6 +211,31 @@ public class TestAmFilter {
       return url;
     }
 
+    @Override
+    public void setStatus(int status) {
+      this.status = status;
     }
 
+    @Override
+    public void setContentType(String type) {
+      this.contentType = type;
+    }
+
+    @Override
+    public void setHeader(String name, String value) {
+      headers.put(name, value);
+    }
+
+    public String getHeader(String name) {
+      return headers.get(name);
+    }
+
+    @Override
+    public PrintWriter getWriter() throws IOException {
+      body = new StringWriter();
+      return new PrintWriter(body);
+    }
+  }
+
+  
 }