HDFS-14522. Allow compact property description in xml in httpfs.

Author: iwasakims

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/lib/util/ConfigurationUtils.java

@@ -20,17 +20,7 @@
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
-import org.w3c.dom.DOMException;
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.Node;
-import org.w3c.dom.NodeList;
-import org.w3c.dom.Text;
-import org.xml.sax.SAXException;
 
-import javax.xml.parsers.DocumentBuilder;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.ParserConfigurationException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Map;
@@ -98,62 +88,6 @@ public static Configuration resolve(Configuration conf) {
    * @throws IOException thrown if the configuration could not be read.
    */
   public static void load(Configuration conf, InputStream is) throws IOException {
-    try {
-      DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
-      // ignore all comments inside the xml file
-      docBuilderFactory.setIgnoringComments(true);
-      DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();
-      Document doc = builder.parse(is);
-      parseDocument(conf, doc);
-    } catch (SAXException e) {
-      throw new IOException(e);
-    } catch (ParserConfigurationException e) {
-      throw new IOException(e);
-    }
-  }
-
-  // Canibalized from FileSystemAccess <code>Configuration.loadResource()</code>.
-  private static void parseDocument(Configuration conf, Document doc) throws IOException {
-    try {
-      Element root = doc.getDocumentElement();
-      if (!"configuration".equals(root.getTagName())) {
-        throw new IOException("bad conf file: top-level element not <configuration>");
-      }
-      NodeList props = root.getChildNodes();
-      for (int i = 0; i < props.getLength(); i++) {
-        Node propNode = props.item(i);
-        if (!(propNode instanceof Element)) {
-          continue;
-        }
-        Element prop = (Element) propNode;
-        if (!"property".equals(prop.getTagName())) {
-          throw new IOException("bad conf file: element not <property>");
-        }
-        NodeList fields = prop.getChildNodes();
-        String attr = null;
-        String value = null;
-        for (int j = 0; j < fields.getLength(); j++) {
-          Node fieldNode = fields.item(j);
-          if (!(fieldNode instanceof Element)) {
-            continue;
-          }
-          Element field = (Element) fieldNode;
-          if ("name".equals(field.getTagName()) && field.hasChildNodes()) {
-            attr = ((Text) field.getFirstChild()).getData().trim();
-          }
-          if ("value".equals(field.getTagName()) && field.hasChildNodes()) {
-            value = ((Text) field.getFirstChild()).getData();
-          }
-        }
-
-        if (attr != null && value != null) {
-          conf.set(attr, value);
-        }
-      }
-
-    } catch (DOMException e) {
-      throw new IOException(e);
-    }
+    conf.addResource(is);
   }
-
 }

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/lib/util/TestConfigurationUtils.java

@@ -21,9 +21,11 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 
+import java.io.BufferedWriter;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.StringWriter;
 
 import org.apache.hadoop.conf.Configuration;
 import org.junit.Test;
@@ -44,11 +46,12 @@ public void constructors() throws Exception {
   }
 
 
-  @Test(expected = IOException.class)
-  public void constructorsFail3() throws Exception {
-    InputStream is = new ByteArrayInputStream("<xonfiguration></xonfiguration>".getBytes());
+  @Test
+  public void constructors3() throws Exception {
+    InputStream is = new ByteArrayInputStream("<xonfiguration><property name=\"key1\" value=\"val1\"/></xonfiguration>".getBytes());
     Configuration conf = new Configuration(false);
     ConfigurationUtils.load(conf, is);
+    assertEquals(conf.get("key1"), "val1");
   }
 
   @Test
@@ -124,4 +127,22 @@ public void testVarResolutionAndSysProps() {
     assertEquals(conf.get("user.name"), "foo");
   }
 
+  @Test
+  public void testCompactFormatProperty() throws IOException {
+    Configuration conf = new Configuration(false);
+    assertEquals(conf.size(), 0);
+    StringWriter writer = new StringWriter();
+    BufferedWriter out = new BufferedWriter(writer);
+    out.write("<?xml version=\"1.0\"?>\n");
+    out.write("<configuration>\n");
+    out.write("<property name=\"key1\" value=\"val1\"/>");
+    out.write("</configuration>\n");
+    out.flush();
+    out.close();
+    InputStream is = new ByteArrayInputStream(writer.toString().getBytes());
+    conf = new Configuration(false);
+    ConfigurationUtils.load(conf, is);
+    assertEquals(conf.size(), 1);
+    assertEquals(conf.get("key1"), "val1");
+  }
 }