HDFS-8102. Separate webhdfs retry configuration keys from DFSConfigKeys. Contributed by Haohui Mai.

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/HdfsClientConfigKeys.java

@@ -60,4 +60,21 @@ public interface HdfsClientConfigKeys {
     public static final int     WINDOW_BASE_DEFAULT
         = 3000;
   }
+
+  // WebHDFS retry configuration policy
+  interface WebHdfsRetry {
+    String  PREFIX = HdfsClientConfigKeys.PREFIX + "http.client.";
+    String  RETRY_POLICY_ENABLED_KEY = PREFIX + "dfs.http.client.retry.policy.enabled";
+    boolean RETRY_POLICY_ENABLED_DEFAULT = false;
+    String  RETRY_POLICY_SPEC_KEY = PREFIX + "dfs.http.client.retry.policy.spec";
+    String  RETRY_POLICY_SPEC_DEFAULT = "10000,6,60000,10"; //t1,n1,t2,n2,...
+    String  FAILOVER_MAX_ATTEMPTS_KEY = PREFIX + "dfs.http.client.failover.max.attempts";
+    int     FAILOVER_MAX_ATTEMPTS_DEFAULT =  15;
+    String  RETRY_MAX_ATTEMPTS_KEY = PREFIX + "dfs.http.client.retry.max.attempts";
+    int     RETRY_MAX_ATTEMPTS_DEFAULT = 10;
+    String  FAILOVER_SLEEPTIME_BASE_KEY = PREFIX + "dfs.http.client.failover.sleep.base.millis";
+    int     FAILOVER_SLEEPTIME_BASE_DEFAULT = 500;
+    String  FAILOVER_SLEEPTIME_MAX_KEY = PREFIX + "dfs.http.client.failover.sleep.max.millis";
+    int     FAILOVER_SLEEPTIME_MAX_DEFAULT =  15000;
+  }
 }

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

@@ -412,6 +412,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-8099. Change "DFSInputStream has been closed already" message to
     debug log level (Charles Lamb via Colin P. McCabe)
 
+    HDFS-8102. Separate webhdfs retry configuration keys from DFSConfigKeys.
+    (wheat9)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

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

@@ -601,19 +601,43 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final long   DFS_DATANODE_XCEIVER_STOP_TIMEOUT_MILLIS_DEFAULT = 60000;
 
   // WebHDFS retry policy
-  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_KEY = "dfs.http.client.retry.policy.enabled";
-  public static final boolean DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_DEFAULT = false;
-  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_KEY = "dfs.http.client.retry.policy.spec";
-  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_DEFAULT = "10000,6,60000,10"; //t1,n1,t2,n2,...
-  public static final String  DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_KEY = "dfs.http.client.failover.max.attempts";
-  public static final int     DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_DEFAULT = 15;
-  public static final String  DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_KEY = "dfs.http.client.retry.max.attempts";
-  public static final int     DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_DEFAULT = 10;
-  public static final String  DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_KEY = "dfs.http.client.failover.sleep.base.millis";
-  public static final int     DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_DEFAULT = 500;
-  public static final String  DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_KEY = "dfs.http.client.failover.sleep.max.millis";
-  public static final int     DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_DEFAULT = 15000;
-  
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_ENABLED_KEY;
+  @Deprecated
+  public static final boolean DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_DEFAULT =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_ENABLED_DEFAULT;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_SPEC_KEY;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_DEFAULT =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_SPEC_DEFAULT;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_MAX_ATTEMPTS_KEY;
+  @Deprecated
+  public static final int     DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_DEFAULT =
+      HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_MAX_ATTEMPTS_DEFAULT;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_MAX_ATTEMPTS_KEY;
+  @Deprecated
+  public static final int     DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_DEFAULT =
+      HdfsClientConfigKeys.WebHdfsRetry.RETRY_MAX_ATTEMPTS_DEFAULT;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_BASE_KEY;
+  @Deprecated
+  public static final int     DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_DEFAULT =
+      HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_BASE_DEFAULT;
+  @Deprecated
+  public static final String  DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_KEY =
+      HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_MAX_KEY;
+  @Deprecated
+  public static final int     DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_DEFAULT
+      = HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_MAX_DEFAULT;
+
   // Handling unresolved DN topology mapping
   public static final String  DFS_REJECT_UNRESOLVED_DN_TOPOLOGY_MAPPING_KEY = 
       "dfs.namenode.reject-unresolved-dn-topology-mapping";

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -59,6 +59,7 @@ import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.HAUtil;
+import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
 import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
 import org.apache.hadoop.hdfs.server.namenode.SafeModeException;
@@ -172,25 +173,25 @@ public class WebHdfsFileSystem extends FileSystem
       this.retryPolicy =
           RetryUtils.getDefaultRetryPolicy(
               conf,
-              DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_KEY,
-              DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_DEFAULT,
-              DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_KEY,
-              DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_POLICY_SPEC_DEFAULT,
+              HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_ENABLED_KEY,
+              HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_ENABLED_DEFAULT,
+              HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_SPEC_KEY,
+              HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_SPEC_DEFAULT,
               SafeModeException.class);
     } else {
 
       int maxFailoverAttempts = conf.getInt(
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_KEY,
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_MAX_ATTEMPTS_DEFAULT);
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_MAX_ATTEMPTS_KEY,
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_MAX_ATTEMPTS_DEFAULT);
       int maxRetryAttempts = conf.getInt(
-          DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_KEY,
-          DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_MAX_ATTEMPTS_DEFAULT);
+          HdfsClientConfigKeys.WebHdfsRetry.RETRY_MAX_ATTEMPTS_KEY,
+          HdfsClientConfigKeys.WebHdfsRetry.RETRY_MAX_ATTEMPTS_DEFAULT);
       int failoverSleepBaseMillis = conf.getInt(
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_KEY,
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_BASE_DEFAULT);
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_BASE_KEY,
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_BASE_DEFAULT);
       int failoverSleepMaxMillis = conf.getInt(
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_KEY,
-          DFSConfigKeys.DFS_HTTP_CLIENT_FAILOVER_SLEEPTIME_MAX_DEFAULT);
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_MAX_KEY,
+          HdfsClientConfigKeys.WebHdfsRetry.FAILOVER_SLEEPTIME_MAX_DEFAULT);
 
       this.retryPolicy = RetryPolicies
           .failoverOnNetworkException(RetryPolicies.TRY_ONCE_THEN_FAIL,

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSClientRetries.java

@@ -875,7 +875,7 @@ public class TestDFSClientRetries {
     final Path dir = new Path("/testNamenodeRestart");
 
     if (isWebHDFS) {
-      conf.setBoolean(DFSConfigKeys.DFS_HTTP_CLIENT_RETRY_POLICY_ENABLED_KEY, true);
+      conf.setBoolean(HdfsClientConfigKeys.WebHdfsRetry.RETRY_POLICY_ENABLED_KEY, true);
     } else {
       conf.setBoolean(HdfsClientConfigKeys.Retry.POLICY_ENABLED_KEY, true);
     }