YARN-5951. Changes to allow CapacityScheduler to use configuration store

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacityScheduler.java

@@ -19,7 +19,6 @@
 package org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity;
 
 import java.io.IOException;
-import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.EnumSet;
@@ -103,6 +102,8 @@ import org.apache.hadoop.yarn.server.resourcemanager.scheduler.activities.Activi
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.activities.ActivityDiagnosticConstant;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.activities.ActivityState;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.activities.AllocationState;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.conf.CSConfigurationProvider;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.conf.FileBasedCSConfigurationProvider;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.preemption.KillableContainer;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.preemption.PreemptionManager;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.common.AssignmentInformation;
@@ -167,6 +168,8 @@ public class CapacityScheduler extends
 
   private int maxAssignPerHeartbeat;
 
+  private CSConfigurationProvider csConfProvider;
+
   @Override
   public void setConf(Configuration conf) {
       yarnConf = conf;
@@ -289,7 +292,18 @@ public class CapacityScheduler extends
       IOException {
     try {
       writeLock.lock();
-      this.conf = loadCapacitySchedulerConfiguration(configuration);
+      String confProviderStr = configuration.get(
+          CapacitySchedulerConfiguration.CS_CONF_PROVIDER,
+          CapacitySchedulerConfiguration.DEFAULT_CS_CONF_PROVIDER);
+      if (confProviderStr.equals(
+          CapacitySchedulerConfiguration.FILE_CS_CONF_PROVIDER)) {
+        this.csConfProvider = new FileBasedCSConfigurationProvider(rmContext);
+      } else {
+        throw new IOException("Invalid CS configuration provider: " +
+            confProviderStr);
+      }
+      this.csConfProvider.init(configuration);
+      this.conf = this.csConfProvider.loadConfiguration(configuration);
       validateConf(this.conf);
       this.minimumAllocation = super.getMinimumAllocation();
       initMaximumResourceCapability(super.getMaximumAllocation());
@@ -399,7 +413,7 @@ public class CapacityScheduler extends
       writeLock.lock();
       Configuration configuration = new Configuration(newConf);
       CapacitySchedulerConfiguration oldConf = this.conf;
-      this.conf = loadCapacitySchedulerConfiguration(configuration);
+      this.conf = csConfProvider.loadConfiguration(configuration);
       validateConf(this.conf);
       try {
         LOG.info("Re-initializing queues...");
@@ -1831,23 +1845,6 @@ public class CapacityScheduler extends
     return true;
   }
 
-  private CapacitySchedulerConfiguration loadCapacitySchedulerConfiguration(
-      Configuration configuration) throws IOException {
-    try {
-      InputStream CSInputStream =
-          this.rmContext.getConfigurationProvider()
-              .getConfigurationInputStream(configuration,
-                  YarnConfiguration.CS_CONFIGURATION_FILE);
-      if (CSInputStream != null) {
-        configuration.addResource(CSInputStream);
-        return new CapacitySchedulerConfiguration(configuration, false);
-      }
-      return new CapacitySchedulerConfiguration(configuration, true);
-    } catch (Exception e) {
-      throw new IOException(e);
-    }
-  }
-
   private String getDefaultReservationQueueName(String planQueueName) {
     return planQueueName + ReservationConstants.DEFAULT_QUEUE_SUFFIX;
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/CapacitySchedulerConfiguration.java

@@ -315,6 +315,15 @@ public class CapacitySchedulerConfiguration extends ReservationSchedulerConfigur
 
   @Private
   public static final int DEFAULT_MAX_ASSIGN_PER_HEARTBEAT = -1;
+  
+  public static final String CS_CONF_PROVIDER = PREFIX
+      + "configuration.provider";
+
+  @Private
+  public static final String FILE_CS_CONF_PROVIDER = "file";
+
+  @Private
+  public static final String DEFAULT_CS_CONF_PROVIDER = FILE_CS_CONF_PROVIDER;
 
   AppPriorityACLConfigurationParser priorityACLConfig = new AppPriorityACLConfigurationParser();
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/CSConfigurationProvider.java

@@ -0,0 +1,46 @@
+/**
+ * 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.server.resourcemanager.scheduler.capacity.conf;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration;
+
+import java.io.IOException;
+
+/**
+ * Configuration provider for {@link CapacityScheduler}.
+ */
+public interface CSConfigurationProvider {
+
+  /**
+   * Initialize the configuration provider with given conf.
+   * @param conf configuration to initialize with
+   */
+  void init(Configuration conf);
+
+  /**
+   * Loads capacity scheduler configuration object.
+   * @param conf initial bootstrap configuration
+   * @return CS configuration
+   * @throws IOException if fail to retrieve configuration
+   */
+  CapacitySchedulerConfiguration loadConfiguration(Configuration conf)
+      throws IOException;
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/FileBasedCSConfigurationProvider.java

@@ -0,0 +1,67 @@
+/**
+ * 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.server.resourcemanager.scheduler.capacity.conf;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.resourcemanager.RMContext;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacityScheduler;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.CapacitySchedulerConfiguration;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * {@link CapacityScheduler} configuration provider based on local
+ * {@code capacity-scheduler.xml} file.
+ */
+public class FileBasedCSConfigurationProvider implements
+    CSConfigurationProvider {
+
+  private RMContext rmContext;
+
+  /**
+   * Construct file based CS configuration provider with given context.
+   * @param rmContext the RM context
+   */
+  public FileBasedCSConfigurationProvider(RMContext rmContext) {
+    this.rmContext = rmContext;
+  }
+
+  @Override
+  public void init(Configuration conf) {}
+
+  @Override
+  public CapacitySchedulerConfiguration loadConfiguration(Configuration conf)
+      throws IOException {
+    try {
+      InputStream csInputStream =
+          this.rmContext.getConfigurationProvider()
+              .getConfigurationInputStream(conf,
+                  YarnConfiguration.CS_CONFIGURATION_FILE);
+      if (csInputStream != null) {
+        conf.addResource(csInputStream);
+        return new CapacitySchedulerConfiguration(conf, false);
+      }
+      return new CapacitySchedulerConfiguration(conf, true);
+    } catch (Exception e) {
+      throw new IOException(e);
+    }
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/package-info.java

@@ -0,0 +1,29 @@
+/*
+ * 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.server.resourcemanager.scheduler.capacity.conf
+ * contains classes related to capacity scheduler configuration management.
+ */
+@InterfaceAudience.Private
+@InterfaceStability.Unstable
+package org.apache.hadoop.yarn.server.resourcemanager.scheduler.capacity.conf;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/TestCapacityScheduler.java

@@ -241,13 +241,13 @@ public class TestCapacityScheduler {
 
   @Test (timeout = 30000)
   public void testConfValidation() throws Exception {
-    ResourceScheduler scheduler = new CapacityScheduler();
+    CapacityScheduler scheduler = new CapacityScheduler();
     scheduler.setRMContext(resourceManager.getRMContext());
     Configuration conf = new YarnConfiguration();
     conf.setInt(YarnConfiguration.RM_SCHEDULER_MINIMUM_ALLOCATION_MB, 2048);
     conf.setInt(YarnConfiguration.RM_SCHEDULER_MAXIMUM_ALLOCATION_MB, 1024);
     try {
-      scheduler.reinitialize(conf, mockContext);
+      scheduler.init(conf);
       fail("Exception is expected because the min memory allocation is" +
         " larger than the max memory allocation.");
     } catch (YarnRuntimeException e) {