YARN-410. Fixed RM UI so that the new lines diagnostics for a failed app on the per-application page are translated to html line breaks. Contributed by Omkar Vinit Joshi

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1453638 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -25,6 +25,10 @@ Release 0.23.7 - UNRELEASED
     YARN-227. Application expiration difficult to debug for end-users
     (Jason Lowe via jeagles)
 
+    YARN-410. Fixed RM UI so that the new lines diagnostics for a failed app on
+    the per-application page are translated to html line breaks. (Omkar Vinit
+    Joshi via vinodkv)
+
   OPTIMIZATIONS
 
     YARN-357. App submission should not be synchronized (daryn)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/view/InfoBlock.java

@@ -20,7 +20,11 @@ package org.apache.hadoop.yarn.webapp.view;
 
 import org.apache.hadoop.yarn.webapp.ResponseInfo;
 import org.apache.hadoop.yarn.webapp.hamlet.Hamlet;
-import org.apache.hadoop.yarn.webapp.hamlet.Hamlet.*;
+import org.apache.hadoop.yarn.webapp.hamlet.Hamlet.DIV;
+import org.apache.hadoop.yarn.webapp.hamlet.Hamlet.TABLE;
+import org.apache.hadoop.yarn.webapp.hamlet.Hamlet.TD;
+import org.apache.hadoop.yarn.webapp.hamlet.Hamlet.TR;
+
 
 import com.google.inject.Inject;
 
@@ -47,7 +51,19 @@ public class InfoBlock extends HtmlBlock {
       String value = String.valueOf(item.value);
       if (item.url == null) {
         if (!item.isRaw) {
-          tr.td(value);
+          TD<TR<TABLE<DIV<Hamlet>>>> td = tr.td();
+          if ( value.lastIndexOf('\n') > 0) {
+            String []lines = value.split("\n");
+        	DIV<TD<TR<TABLE<DIV<Hamlet>>>>> singleLineDiv;
+            for ( String line :lines) {
+              singleLineDiv = td.div();
+              singleLineDiv._r(line);
+              singleLineDiv._();
+            }
+          } else {
+            td._r(value);
+          }
+          td._();
         } else {
           tr.td()._r(value)._();
         }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/webapp/view/TestInfoBlock.java

@@ -0,0 +1,81 @@
+/**
+* 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.webapp.view;
+
+import java.io.PrintWriter;
+import java.io.StringWriter;
+
+import static org.junit.Assert.assertTrue;
+
+import org.apache.hadoop.yarn.webapp.ResponseInfo;
+import org.apache.hadoop.yarn.webapp.test.WebAppTests;
+import org.junit.Before;
+import org.junit.Test;
+
+public class TestInfoBlock {
+
+  public static StringWriter sw;
+
+  public static PrintWriter pw;
+
+  public static class MultilineInfoBlock extends InfoBlock{
+    
+    static ResponseInfo resInfo;
+
+    static {
+      resInfo = new ResponseInfo();
+      resInfo._("Single_line_value", "This is one line.");
+      resInfo._("Multiple_line_value", "This is first line.\nThis is second line.");	
+    }
+
+    @Override
+    public PrintWriter writer() {
+      return TestInfoBlock.pw;
+    }
+
+    MultilineInfoBlock(ResponseInfo info) {
+      super(resInfo);
+    }
+
+    public MultilineInfoBlock() {
+      super(resInfo);
+    }
+  }
+
+  @Before
+  public void setup() {
+    sw = new StringWriter();
+    pw = new PrintWriter(sw);
+  }
+
+  @Test(timeout=60000L)
+  public void testMultilineInfoBlock() throws Exception{
+
+    WebAppTests.testBlock(MultilineInfoBlock.class);
+    TestInfoBlock.pw.flush();
+    String output = TestInfoBlock.sw.toString().replaceAll(" +", " ");
+    String expectedSinglelineData = "<tr class=\"odd\">\n"
+      + " <th>\n Single_line_value\n <td>\n This is one line.\n";
+    String expectedMultilineData = "<tr class=\"even\">\n"
+      + " <th>\n Multiple_line_value\n <td>\n <div>\n"
+      + " This is first line.\n </div>\n <div>\n"
+      + " This is second line.\n </div>\n";
+    assertTrue(output.contains(expectedSinglelineData) && output.contains(expectedMultilineData));
+  }
+}