MetaStore.java

/**
 * Copyright 2016 Yahoo Inc.
 *
 * Licensed 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.bookkeeper.mledger.impl;

import java.util.List;

import org.apache.bookkeeper.mledger.ManagedLedgerException.MetaStoreException;
import org.apache.bookkeeper.mledger.proto.MLDataFormats.ManagedCursorInfo;
import org.apache.bookkeeper.mledger.proto.MLDataFormats.ManagedLedgerInfo;

/**
 * Interface that describes the operations that the ManagedLedger need to do on the metadata store.
 */
public interface MetaStore {

    public static interface Stat {
        int getVersion();
        long getCreationTimestamp();
        long getModificationTimestamp();
    }

    public static interface UpdateLedgersIdsCallback {
        void updateLedgersIdsComplete(MetaStoreException status, Stat stat);
    }

    public static interface MetaStoreCallback<T> {
        void operationComplete(T result, Stat stat);

        void operationFailed(MetaStoreException e);
    }

    /**
     * Get the metadata used by the ManagedLedger
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     * @return a version object and a list of LedgerStats
     * @throws MetaStoreException
     */
    void getManagedLedgerInfo(String ledgerName, MetaStoreCallback<ManagedLedgerInfo> callback);

    /**
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     *
     * @param ManagedLedgerInfo
     *            the metadata object to be persisted
     * @param version
     *            version object associated with current state
     * @param callback
     *            callback object
     * @param ctx
     *            opaque context object
     */
    void asyncUpdateLedgerIds(String ledgerName, ManagedLedgerInfo mlInfo, Stat version,
            MetaStoreCallback<Void> callback);

    /**
     * Get the list of cursors registered on a ManagedLedger.
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     * @return a list of the consumer Ids
     * @throws MetaStoreException
     */
    void getCursors(String ledgerName, MetaStoreCallback<List<String>> callback);

    /**
     * Get the ledger id associated with a cursor.
     *
     * This ledger id will contains the mark-deleted position for the cursor.
     *
     * @param ledgerName
     * @param cursorName
     * @param callback
     */
    void asyncGetCursorInfo(String ledgerName, String cursorName, MetaStoreCallback<ManagedCursorInfo> callback);

    /**
     * Update the persisted position of a cursor
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     * @param cursorName
     * @param ledgerId
     * @param callback
     *            the callback
     * @throws MetaStoreException
     */
    void asyncUpdateCursorInfo(String ledgerName, String cursorName, ManagedCursorInfo info, Stat version,
            MetaStoreCallback<Void> callback);

    /**
     * Drop the persistent state of a consumer from the metadata store
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     * @param cursorName
     *            the cursor name
     * @param callback
     *            callback object
     */
    void asyncRemoveCursor(String ledgerName, String cursorName, MetaStoreCallback<Void> callback);

    /**
     * Drop the persistent state for the ManagedLedger and all its associated consumers.
     *
     * @param ledgerName
     *            the name of the ManagedLedger
     * @param callback
     *            callback object
     */
    void removeManagedLedger(String ledgerName, MetaStoreCallback<Void> callback);

    /**
     * Get a list of all the managed ledgers in the system
     *
     * @return an Iterable of the names of the managed ledgers
     * @throws MetaStoreException
     */
    Iterable<String> getManagedLedgers() throws MetaStoreException;
}