+/*
+ * Copyright (c) 2016 Cisco 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.persisted;
+
+import com.google.common.annotations.Beta;
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import javax.annotation.Nonnull;
+import org.opendaylight.yangtools.concepts.WritableObject;
+
+/**
+ * Enumeration of all ABI versions supported by this implementation of persistence. An ABI version has to be bumped
+ * whenever:
+ * - a new event is defined
+ * - serialization format is changed
+ *
+ * This version effectively defines the protocol version between actors participating on a particular shard. A shard
+ * participant instance should oppose RAFT candidates which produce persistence of an unsupported version. If a follower
+ * encounters an unsupported version it must not become fully-operational, as it does not have an accurate view
+ * of shard state.
+ *
+ * @author Robert Varga
+ */
+@Beta
+public enum PayloadVersion implements WritableObject {
+ // NOTE: enumeration values need to be sorted in asceding order of their version to keep Comparable working
+
+ /**
+ * Version which is older than any other version. This version exists purely for testing purposes.
+ */
+ @VisibleForTesting
+ TEST_PAST_VERSION(0),
+
+ /**
+ * Initial ABI version, as shipped with Boron Simultaneous release.
+ */
+ // We seed the initial version to be the same as DataStoreVersions.BORON-VERSION for compatibility reasons.
+ BORON(5),
+
+ /**
+ * Version which is newer than any other version. This version exists purely for testing purposes.
+ */
+ @VisibleForTesting
+ TEST_FUTURE_VERSION(65535);
+
+ private final short value;
+
+ PayloadVersion(final int intVersion) {
+ Preconditions.checkArgument(intVersion >= 0 && intVersion <= 65535);
+ value = (short) intVersion;
+ }
+
+ /**
+ * Return the unsigned short integer identifying this version.
+ *
+ * @return Unsigned short integer identifying this version
+ */
+ public short shortValue() {
+ return value;
+ }
+
+ /**
+ * Return the codebase-native persistence version. This version is the default version allocated to messages
+ * at runtime. Conversion to previous versions may incur additional overhead (such as object allocation).
+ *
+ * @return Current {@link PayloadVersion}
+ */
+ public static @Nonnull PayloadVersion current() {
+ return BORON;
+ }
+
+ /**
+ * Return the {@link PayloadVersion} corresponding to an unsigned short integer. This method is provided for callers
+ * which provide their own recovery strategy in case of version incompatibility.
+ *
+ * @param s Short integer as returned from {@link #shortValue()}
+ * @return {@link PayloadVersion}
+ * @throws FutureVersionException if the specified integer identifies a future version
+ * @throws PastVersionException if the specified integer identifies a past version which is no longer supported
+ */
+ public static @Nonnull PayloadVersion valueOf(final short s) throws FutureVersionException, PastVersionException {
+ switch (Short.toUnsignedInt(s)) {
+ case 0:
+ case 1:
+ case 2:
+ case 3:
+ case 4:
+ throw new PastVersionException(s, BORON);
+ case 5:
+ return BORON;
+ default:
+ throw new FutureVersionException(s, BORON);
+ }
+ }
+
+ @Override
+ public void writeTo(final DataOutput out) throws IOException {
+ out.writeShort(value);
+ }
+
+ /**
+ * Read an {@link PayloadVersion} from a {@link DataInput}. This method is provided for callers which do not have
+ * a recovery strategy for dealing with unsupported versions.
+ *
+ * @param in Input from which to read
+ * @return An {@link PayloadVersion}
+ * @throws IOException If read fails or an unsupported version is encountered
+ */
+ public static @Nonnull PayloadVersion readFrom(final @Nonnull DataInput in) throws IOException {
+ final short s = in.readShort();
+ try {
+ return valueOf(s);
+ } catch (FutureVersionException | PastVersionException e) {
+ throw new IOException("Unsupported version", e);
+ }
+ }
+
+}
Code Review / controller.git / commitdiff