HDDS-242. Introduce NEW_NODE, STALE_NODE and DEAD_NODE event

and corresponding event handlers in SCM.
Contributed by Nanda Kumar.

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/ContainerReportHandler.java

@@ -0,0 +1,47 @@
+/**
+ * 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.hdds.scm.container;
+
+import org.apache.hadoop.hdds.scm.node.states.Node2ContainerMap;
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeHeartbeatDispatcher
+    .ContainerReportFromDatanode;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+
+/**
+ * Handles container reports from datanode.
+ */
+public class ContainerReportHandler implements
+    EventHandler<ContainerReportFromDatanode> {
+
+  private final Mapping containerMapping;
+  private final Node2ContainerMap node2ContainerMap;
+
+  public ContainerReportHandler(Mapping containerMapping,
+                                Node2ContainerMap node2ContainerMap) {
+    this.containerMapping = containerMapping;
+    this.node2ContainerMap = node2ContainerMap;
+  }
+
+  @Override
+  public void onMessage(ContainerReportFromDatanode containerReportFromDatanode,
+                        EventPublisher publisher) {
+    // TODO: process container report.
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/node/DeadNodeHandler.java

@@ -0,0 +1,42 @@
+/**
+ * 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.hdds.scm.node;
+
+import org.apache.hadoop.hdds.protocol.DatanodeDetails;
+import org.apache.hadoop.hdds.scm.node.states.Node2ContainerMap;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+
+/**
+ * Handles Dead Node event.
+ */
+public class DeadNodeHandler implements EventHandler<DatanodeDetails> {
+
+  private final Node2ContainerMap node2ContainerMap;
+
+  public DeadNodeHandler(Node2ContainerMap node2ContainerMap) {
+    this.node2ContainerMap = node2ContainerMap;
+  }
+
+  @Override
+  public void onMessage(DatanodeDetails datanodeDetails,
+                        EventPublisher publisher) {
+    //TODO: add logic to handle dead node.
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/node/NewNodeHandler.java

@@ -0,0 +1,50 @@
+/**
+ * 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.hdds.scm.node;
+
+import org.apache.hadoop.hdds.protocol.DatanodeDetails;
+import org.apache.hadoop.hdds.scm.exceptions.SCMException;
+import org.apache.hadoop.hdds.scm.node.states.Node2ContainerMap;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+
+import java.util.Collections;
+
+/**
+ * Handles New Node event.
+ */
+public class NewNodeHandler implements EventHandler<DatanodeDetails> {
+
+  private final Node2ContainerMap node2ContainerMap;
+
+  public NewNodeHandler(Node2ContainerMap node2ContainerMap) {
+    this.node2ContainerMap = node2ContainerMap;
+  }
+
+  @Override
+  public void onMessage(DatanodeDetails datanodeDetails,
+                        EventPublisher publisher) {
+    try {
+      node2ContainerMap.insertNewDatanode(datanodeDetails.getUuid(),
+          Collections.emptySet());
+    } catch (SCMException e) {
+      // TODO: log exception message.
+    }
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/node/NodeReportHandler.java

@@ -0,0 +1,42 @@
+/**
+ * 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.hdds.scm.node;
+
+import org.apache.hadoop.hdds.scm.server.SCMDatanodeHeartbeatDispatcher
+    .NodeReportFromDatanode;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+
+/**
+ * Handles Node Reports from datanode.
+ */
+public class NodeReportHandler implements EventHandler<NodeReportFromDatanode> {
+
+  private final NodeManager nodeManager;
+
+  public NodeReportHandler(NodeManager nodeManager) {
+    this.nodeManager = nodeManager;
+  }
+
+  @Override
+  public void onMessage(NodeReportFromDatanode nodeReportFromDatanode,
+                        EventPublisher publisher) {
+    //TODO: process node report.
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/node/StaleNodeHandler.java

@@ -0,0 +1,42 @@
+/**
+ * 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.hdds.scm.node;
+
+import org.apache.hadoop.hdds.protocol.DatanodeDetails;
+import org.apache.hadoop.hdds.scm.node.states.Node2ContainerMap;
+import org.apache.hadoop.hdds.server.events.EventHandler;
+import org.apache.hadoop.hdds.server.events.EventPublisher;
+
+/**
+ * Handles Stale node event.
+ */
+public class StaleNodeHandler implements EventHandler<DatanodeDetails> {
+
+  private final Node2ContainerMap node2ContainerMap;
+
+  public StaleNodeHandler(Node2ContainerMap node2ContainerMap) {
+    this.node2ContainerMap = node2ContainerMap;
+  }
+
+  @Override
+  public void onMessage(DatanodeDetails datanodeDetails,
+                        EventPublisher publisher) {
+    //TODO: logic to handle stale node.
+  }
+}

hadoop-ozone/common/src/main/bin/ozone-config.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+
+# 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.
+
+# included in all the ozone scripts with source command
+# should not be executed directly
+
+function hadoop_subproject_init
+{
+  if [[ -z "${HADOOP_OZONE_ENV_PROCESSED}" ]]; then
+    if [[ -e "${HADOOP_CONF_DIR}/hdfs-env.sh" ]]; then
+      . "${HADOOP_CONF_DIR}/hdfs-env.sh"
+      export HADOOP_OZONES_ENV_PROCESSED=true
+    fi
+  fi
+  HADOOP_OZONE_HOME="${HADOOP_OZONE_HOME:-$HADOOP_HOME}"
+
+}
+
+if [[ -z "${HADOOP_LIBEXEC_DIR}" ]]; then
+  _hd_this="${BASH_SOURCE-$0}"
+  HADOOP_LIBEXEC_DIR=$(cd -P -- "$(dirname -- "${_hd_this}")" >/dev/null && pwd -P)
+fi
+
+# shellcheck source=./hadoop-common-project/hadoop-common/src/main/bin/hadoop-config.sh
+
+if [[ -n "${HADOOP_COMMON_HOME}" ]] &&
+   [[ -e "${HADOOP_COMMON_HOME}/libexec/hadoop-config.sh" ]]; then
+  . "${HADOOP_COMMON_HOME}/libexec/hadoop-config.sh"
+elif [[ -e "${HADOOP_LIBEXEC_DIR}/hadoop-config.sh" ]]; then
+  . "${HADOOP_LIBEXEC_DIR}/hadoop-config.sh"
+elif [ -e "${HADOOP_HOME}/libexec/hadoop-config.sh" ]; then
+  . "${HADOOP_HOME}/libexec/hadoop-config.sh"
+else
+  echo "ERROR: Hadoop common not found." 2>&1
+  exit 1
+fi
+