Adobe-Consulting-Services/acs-aem-commons

/*
 * ACS AEM Commons
 *
 * Copyright (C) 2013 - 2023 Adobe
 *
 * 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 com.adobe.acs.commons.httpcache.store.jcr.impl.visitor;

import javax.jcr.Node;
import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.jcr.util.TraversingItemVisitor;

import org.apache.jackrabbit.oak.spi.security.authorization.accesscontrol.AccessControlConstants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.adobe.acs.commons.httpcache.store.jcr.impl.JCRHttpCacheStoreConstants;

public abstract class AbstractNodeVisitor extends TraversingItemVisitor.Default
{
    private static final Logger log = LoggerFactory.getLogger(AbstractNodeVisitor.class);
    private static final long WARN_THRESHOLD = 2000;

    private final long deltaSaveThreshold;
    private final long startTimeInMs = System.currentTimeMillis();
    private long delta = 0;
    private long evictionCount = 0;
    private long loopCounter = 0;
    private Session session;


    public AbstractNodeVisitor( int maxLevel, long deltaSaveThreshold) {
        super(false, maxLevel);
        this.deltaSaveThreshold = deltaSaveThreshold;
    }

    public void visit(Node node) throws RepositoryException {
        session = node.getSession();
        super.visit(node);
    }

    public void close() throws RepositoryException
    {
        if(delta > 0){
            session.save();
            delta = 0;
        }
    }

    protected void entering(Node node, int level) throws RepositoryException {
        loopCounter++;
        logPossibleOverload();
    }

    protected void leaving(Node node, int level)
            throws RepositoryException{
        logPossibleOverload();
    }

    private void logPossibleOverload(){
        long current = System.currentTimeMillis();
        if((loopCounter % 10 == 0) && startTimeInMs + WARN_THRESHOLD < current){
            log.warn("Visiting the JCR cache with the {} is taking too long! taking {} seconds", getClass().getSimpleName(), (current - startTimeInMs / 1000));
        }
    }


    public static boolean isCacheEntryNode(final Node node) throws RepositoryException
    {
        return node.hasProperty(JCRHttpCacheStoreConstants.PN_ISCACHEENTRYNODE);
    }

    public static boolean isEmptyBucketNode(final Node node) throws RepositoryException
    {
        return  isBucketNode(node)
                && !node.hasNodes();
    }

    public static boolean isBucketNode(final Node node) throws RepositoryException{
        return node.hasProperty(JCRHttpCacheStoreConstants.PN_ISBUCKETNODE);
    }

    protected void persistSession() throws RepositoryException
    {
        if(delta > deltaSaveThreshold){
            session.save();
            delta = 0;
        }

        delta++;
        evictionCount++;
    }

    public long getEvictionCount()
    {
        return evictionCount;
    }
}