From af3aadf04f0d6aff19fff99fe18c9b3feae2c529 Mon Sep 17 00:00:00 2001
From: Allen Wittenauer <aw@apache.org>
Date: Thu, 5 Feb 2015 19:09:37 -0800
Subject: [PATCH] HADOOP-6964. Allow compact property description in xml (Kengo
 Seki via aw)

---
 .../hadoop-common/CHANGES.txt                 |  3 +
 .../org/apache/hadoop/conf/Configuration.java | 18 +++++-
 .../apache/hadoop/conf/TestConfiguration.java | 55 +++++++++++++++++++
 3 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index aee3a23b60..b323f32f2c 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -160,6 +160,9 @@ Trunk (Unreleased)
     HADOOP-7713. dfs -count -q should label output column (Jonathan Allen
     via aw)
 
+    HADOOP-6964. Allow compact property description in xml (Kengo Seki
+    via aw)
+
   BUG FIXES
 
     HADOOP-11473. test-patch says "-1 overall" even when all checks are +1
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java
index 54ee46d995..8f98d0a89e 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java
@@ -90,6 +90,7 @@
 import org.apache.hadoop.util.StringUtils;
 import org.codehaus.jackson.JsonFactory;
 import org.codehaus.jackson.JsonGenerator;
+import org.w3c.dom.Attr;
 import org.w3c.dom.DOMException;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
@@ -2514,11 +2515,26 @@ private Resource loadResource(Properties properties, Resource wrapper, boolean q
         }
         if (!"property".equals(prop.getTagName()))
           LOG.warn("bad conf file: element not <property>");
-        NodeList fields = prop.getChildNodes();
+
         String attr = null;
         String value = null;
         boolean finalParameter = false;
         LinkedList<String> source = new LinkedList<String>();
+
+        Attr propAttr = prop.getAttributeNode("name");
+        if (propAttr != null)
+          attr = StringInterner.weakIntern(propAttr.getValue());
+        propAttr = prop.getAttributeNode("value");
+        if (propAttr != null)
+          value = StringInterner.weakIntern(propAttr.getValue());
+        propAttr = prop.getAttributeNode("final");
+        if (propAttr != null)
+          finalParameter = "true".equals(propAttr.getValue());
+        propAttr = prop.getAttributeNode("source");
+        if (propAttr != null)
+          source.add(StringInterner.weakIntern(propAttr.getValue()));
+
+        NodeList fields = prop.getChildNodes();
         for (int j = 0; j < fields.getLength(); j++) {
           Node fieldNode = fields.item(j);
           if (!(fieldNode instanceof Element))
diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestConfiguration.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestConfiguration.java
index 55bcdc6119..7b4fbb5ba3 100644
--- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestConfiguration.java
+++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestConfiguration.java
@@ -209,6 +209,31 @@ public void testFinalParam() throws IOException {
     assertNull("my var is not final", conf2.get("my.var"));
   }
 
+  public void testCompactFormat() throws IOException {
+    out=new BufferedWriter(new FileWriter(CONFIG));
+    startConfig();
+    appendCompactFormatProperty("a", "b");
+    appendCompactFormatProperty("c", "d", true);
+    appendCompactFormatProperty("e", "f", false, "g");
+    endConfig();
+    Path fileResource = new Path(CONFIG);
+    Configuration conf = new Configuration(false);
+    conf.addResource(fileResource);
+
+    assertEquals("b", conf.get("a"));
+
+    assertEquals("d", conf.get("c"));
+    Set<String> s = conf.getFinalParameters();
+    assertEquals(1, s.size());
+    assertTrue(s.contains("c"));
+
+    assertEquals("f", conf.get("e"));
+    String[] sources = conf.getPropertySources("e");
+    assertEquals(2, sources.length);
+    assertEquals("g", sources[0]);
+    assertEquals(fileResource.toString(), sources[1]);
+  }
+
   public static void assertEq(Object a, Object b) {
     System.out.println("assertEq: " + a + ", " + b);
     assertEquals(a, b);
@@ -264,6 +289,36 @@ void appendProperty(String name, String val, boolean isFinal,
     out.write("</property>\n");
   }
   
+  void appendCompactFormatProperty(String name, String val) throws IOException {
+    appendCompactFormatProperty(name, val, false);
+  }
+
+  void appendCompactFormatProperty(String name, String val, boolean isFinal)
+    throws IOException {
+    appendCompactFormatProperty(name, val, isFinal, null);
+  }
+
+  void appendCompactFormatProperty(String name, String val, boolean isFinal,
+      String source)
+    throws IOException {
+    out.write("<property ");
+    out.write("name=\"");
+    out.write(name);
+    out.write("\" ");
+    out.write("value=\"");
+    out.write(val);
+    out.write("\" ");
+    if (isFinal) {
+      out.write("final=\"true\" ");
+    }
+    if (source != null) {
+      out.write("source=\"");
+      out.write(source);
+      out.write("\" ");
+    }
+    out.write("/>\n");
+  }
+
   public void testOverlay() throws IOException{
     out=new BufferedWriter(new FileWriter(CONFIG));
     startConfig();