Convert DatastoreSnapshotRestore to OSGi DS

[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / DefaultDatastoreSnapshotRestore.java

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/DefaultDatastoreSnapshotRestore.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/DefaultDatastoreSnapshotRestore.java
new file mode 100644 (file)
index 0000000..5fbc7c1
--- /dev/null
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/DefaultDatastoreSnapshotRestore.java
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2015 Brocade Communications Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.cluster.datastore;
+
+import static java.util.Objects.requireNonNull;
+
+import com.google.common.annotations.Beta;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.ObjectInputStream;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+import org.opendaylight.controller.cluster.datastore.persisted.DatastoreSnapshot;
+import org.opendaylight.controller.cluster.datastore.persisted.DatastoreSnapshotList;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This class looks for a previously saved data store backup file in a directory and, if found, de-serializes
+ * the DatastoreSnapshot instances. This class has a static singleton that is created on bundle activation.
+ *
+ * @author Thomas Pantelis
+ */
+@Beta
+@Component(immediate = true)
+public final class DefaultDatastoreSnapshotRestore implements DatastoreSnapshotRestore {
+    private static final Logger LOG = LoggerFactory.getLogger(DefaultDatastoreSnapshotRestore.class);
+
+    private final Map<String, DatastoreSnapshot> datastoreSnapshots = new ConcurrentHashMap<>();
+    private final String restoreDirectoryPath;
+
+    public DefaultDatastoreSnapshotRestore() {
+        this("./clustered-datastore-restore");
+    }
+
+    public DefaultDatastoreSnapshotRestore(final String restoreDirectoryPath) {
+        this.restoreDirectoryPath = requireNonNull(restoreDirectoryPath);
+    }
+
+    @Override
+    public Optional<DatastoreSnapshot> getAndRemove(final String datastoreType) {
+        return Optional.ofNullable(datastoreSnapshots.remove(datastoreType));
+    }
+
+    @Activate
+    @SuppressWarnings("checkstyle:IllegalCatch")
+    void activate() {
+        final File restoreDirectoryFile = new File(restoreDirectoryPath);
+        final String[] files = restoreDirectoryFile.list();
+        if (files == null || files.length == 0) {
+            LOG.debug("Restore directory {} does not exist or is empty", restoreDirectoryFile);
+            return;
+        }
+
+        if (files.length > 1) {
+            LOG.error(
+                "Found {} files in clustered datastore restore directory {} - expected 1. No restore will be attempted",
+                files.length, restoreDirectoryFile);
+            return;
+        }
+
+        final File restoreFile = new File(restoreDirectoryFile, files[0]);
+        LOG.info("Clustered datastore will be restored from file {}", restoreFile);
+
+        try (FileInputStream fis = new FileInputStream(restoreFile)) {
+            DatastoreSnapshotList snapshots = deserialize(fis);
+            LOG.debug("Deserialized {} snapshots", snapshots.size());
+
+            for (DatastoreSnapshot snapshot: snapshots) {
+                datastoreSnapshots.put(snapshot.getType(), snapshot);
+            }
+        } catch (ClassNotFoundException | IOException e) {
+            LOG.error("Error reading clustered datastore restore file {}", restoreFile, e);
+        } finally {
+            if (!restoreFile.delete()) {
+                LOG.error("Could not delete clustered datastore restore file {}", restoreFile);
+            }
+        }
+    }
+
+    private static DatastoreSnapshotList deserialize(final InputStream inputStream)
+            throws IOException, ClassNotFoundException {
+        try (ObjectInputStream ois = new ObjectInputStream(inputStream)) {
+            return (DatastoreSnapshotList) ois.readObject();
+        }
+    }
+}