/*
 * 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.cassandra.db;

import java.util.Collection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.apache.cassandra.concurrent.Stage;
import org.apache.cassandra.concurrent.StageManager;
import org.apache.cassandra.net.IVerbHandler;
import org.apache.cassandra.net.MessageIn;
import org.apache.cassandra.net.MessagingService;
import org.apache.cassandra.utils.WrappedRunnable;

/**
 * Called when node receives updated schema state from the schema migration coordinator node.
 * Such happens when user makes local schema migration on one of the nodes in the ring
 * (which is going to act as coordinator) and that node sends (pushes) it's updated schema state
 * (in form of row mutations) to all the alive nodes in the cluster.
 */
public class DefinitionsUpdateVerbHandler implements IVerbHandler<Collection<RowMutation>>
{
    private static final Logger logger = LoggerFactory.getLogger(DefinitionsUpdateVerbHandler.class);

    public void doVerb(final MessageIn<Collection<RowMutation>> message, String id)
    {
        logger.debug("Received schema mutation push from " + message.from);

        StageManager.getStage(Stage.MIGRATION).submit(new WrappedRunnable()
        {
            public void runMayThrow() throws Exception
            {
                if (message.version < MessagingService.VERSION_117)
                {
                    logger.error("Can't accept schema migrations from Cassandra versions previous to 1.1.7, please upgrade first");
                    return;
                }
                DefsTable.mergeSchema(message.payload);
            }
        });
    }
}