HDFS-3341, HADOOP-8340. SNAPSHOT build versions should compare as less than their eventual release. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1336460 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -164,6 +164,9 @@ Release 2.0.0 - UNRELEASED
     HADOOP-8356. FileSystem service loading mechanism should print the FileSystem 
     impl it is failing to load (tucu)
 
+    HADOOP-8340. SNAPSHOT build versions should compare as less than their eventual
+    final release. (todd)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/VersionUtil.java

@@ -22,11 +22,20 @@ import java.util.regex.Pattern;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 
+import com.google.common.collect.ComparisonChain;
+
 @InterfaceAudience.Private
 public abstract class VersionUtil {
   
   private static final Pattern COMPONENT_GROUPS = Pattern.compile("(\\d+)|(\\D+)");
 
+  /**
+   * Suffix added by maven for nightly builds and other snapshot releases.
+   * These releases are considered to precede the non-SNAPSHOT version
+   * with the same version number.
+   */
+  private static final String SNAPSHOT_SUFFIX = "-SNAPSHOT";
+
   /**
    * This function splits the two versions on "." and performs a
    * naturally-ordered comparison of the resulting components. For example, the
@@ -48,6 +57,11 @@ public abstract class VersionUtil {
    * between the two versions, then the version with fewer components is
    * considered to precede the version with more components.
    * 
+   * In addition to the above rules, there is one special case: maven SNAPSHOT
+   * releases are considered to precede a non-SNAPSHOT release with an
+   * otherwise identical version number. For example, 2.0-SNAPSHOT precedes
+   * 2.0.
+   * 
    * This function returns a negative integer if version1 precedes version2, a
    * positive integer if version2 precedes version1, and 0 if and only if the
    * two versions' components are identical in value and cardinality.
@@ -61,6 +75,11 @@ public abstract class VersionUtil {
    *         versions are equal.
    */
   public static int compareVersions(String version1, String version2) {
+    boolean isSnapshot1 = version1.endsWith(SNAPSHOT_SUFFIX);
+    boolean isSnapshot2 = version2.endsWith(SNAPSHOT_SUFFIX);
+    version1 = stripSnapshotSuffix(version1);
+    version2 = stripSnapshotSuffix(version2);
+    
     String[] version1Parts = version1.split("\\.");
     String[] version2Parts = version2.split("\\.");
     
@@ -87,9 +106,21 @@ public abstract class VersionUtil {
         return component1.length() - component2.length();
       }
     }
-    return version1Parts.length - version2Parts.length;
+    
+    return ComparisonChain.start()
+      .compare(version1Parts.length, version2Parts.length)
+      .compare(isSnapshot2, isSnapshot1)
+      .result();
   }
   
+  private static String stripSnapshotSuffix(String version) {
+    if (version.endsWith(SNAPSHOT_SUFFIX)) {
+      return version.substring(0, version.length() - SNAPSHOT_SUFFIX.length());
+    } else {
+      return version;
+    }
+  }
+
   private static boolean isNumeric(String s) {
     try {
       Integer.parseInt(s);

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/TestVersionUtil.java

@@ -19,7 +19,6 @@ package org.apache.hadoop.util;
 
 import static org.junit.Assert.*;
 
-import org.apache.hadoop.test.GenericTestUtils;
 import org.junit.Test;
 
 public class TestVersionUtil {
@@ -30,6 +29,8 @@ public class TestVersionUtil {
     assertEquals(0, VersionUtil.compareVersions("2.0.0", "2.0.0"));
     assertEquals(0, VersionUtil.compareVersions("2.0.0a", "2.0.0a"));
     assertEquals(0, VersionUtil.compareVersions("1", "1"));
+    assertEquals(0, VersionUtil.compareVersions(
+        "2.0.0-SNAPSHOT", "2.0.0-SNAPSHOT"));
     
     // Assert that lower versions are lower, and higher versions are higher.
     assertExpectedValues("1", "2.0.0");
@@ -52,6 +53,13 @@ public class TestVersionUtil {
     assertExpectedValues("1.0.0a2", "1.0.0a10");
     assertExpectedValues("1.0", "1.a");
     assertExpectedValues("1.0", "1.a0");
+    
+    // Snapshot builds precede their eventual releases.
+    assertExpectedValues("1.0-SNAPSHOT", "1.0");
+    assertExpectedValues("1.0", "1.0.0-SNAPSHOT");
+    assertExpectedValues("1.0.0-SNAPSHOT", "1.0.0");
+    assertExpectedValues("1.0.0", "1.0.1-SNAPSHOT");
+    assertExpectedValues("1.0.1-SNAPSHOT", "1.0.1");
   }
   
   private static void assertExpectedValues(String lower, String higher) {

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -299,6 +299,9 @@ Release 2.0.0 - UNRELEASED
     HDFS-3390. DFSAdmin should print full stack traces of errors when DEBUG
     logging is enabled. (atm)
 
+    HDFS-3341. Change minimum RPC versions to respective SNAPSHOTs instead of
+    final releases. (todd)
+
   OPTIMIZATIONS
 
     HDFS-2477. Optimize computing the diff between a block report and the

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -145,7 +145,7 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final String  DFS_NAMENODE_NUM_EXTRA_EDITS_RETAINED_KEY = "dfs.namenode.num.extra.edits.retained";
   public static final int     DFS_NAMENODE_NUM_EXTRA_EDITS_RETAINED_DEFAULT = 1000000; //1M
   public static final String  DFS_NAMENODE_MIN_SUPPORTED_DATANODE_VERSION_KEY = "dfs.namenode.min.supported.datanode.version";
-  public static final String  DFS_NAMENODE_MIN_SUPPORTED_DATANODE_VERSION_DEFAULT = "2.0.0";
+  public static final String  DFS_NAMENODE_MIN_SUPPORTED_DATANODE_VERSION_DEFAULT = "2.0.0-SNAPSHOT";
 
   public static final String  DFS_NAMENODE_EDITS_DIR_MINIMUM_KEY = "dfs.namenode.edits.dir.minimum";
   public static final int     DFS_NAMENODE_EDITS_DIR_MINIMUM_DEFAULT = 1;
@@ -263,7 +263,7 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final int     DFS_DATANODE_IPC_DEFAULT_PORT = 50020;
   public static final String  DFS_DATANODE_IPC_ADDRESS_DEFAULT = "0.0.0.0" + DFS_DATANODE_IPC_DEFAULT_PORT;
   public static final String  DFS_DATANODE_MIN_SUPPORTED_NAMENODE_VERSION_KEY = "dfs.datanode.min.supported.namenode.version";
-  public static final String  DFS_DATANODE_MIN_SUPPORTED_NAMENODE_VERSION_DEFAULT = "2.0.0";
+  public static final String  DFS_DATANODE_MIN_SUPPORTED_NAMENODE_VERSION_DEFAULT = "2.0.0-SNAPSHOT";
 
   public static final String  DFS_BLOCK_ACCESS_TOKEN_ENABLE_KEY = "dfs.block.access.token.enable";
   public static final boolean DFS_BLOCK_ACCESS_TOKEN_ENABLE_DEFAULT = false;