com.adobe.granite.ui.components.FilteringResourceWrapper Maven / Gradle / Ivy

/*************************************************************************
 *
 * ADOBE CONFIDENTIAL
 * __________________
 *
 *  Copyright 2016 Adobe Systems Incorporated
 *  All Rights Reserved.
 *
 * NOTICE:  All information contained herein is, and remains
 * the property of Adobe Systems Incorporated and its suppliers,
 * if any.  The intellectual and technical concepts contained
 * herein are proprietary to Adobe Systems Incorporated and its
 * suppliers and are protected by trade secret or copyright law.
 * Dissemination of this information or reproduction of this material
 * is strictly forbidden unless prior written permission is obtained
 * from Adobe Systems Incorporated.
 **************************************************************************/
package com.adobe.granite.ui.components;

import java.util.Iterator;

import javax.annotation.Nonnull;

import org.apache.commons.collections4.Predicate;
import org.apache.commons.collections4.Transformer;
import org.apache.commons.collections4.iterators.FilterIterator;
import org.apache.commons.collections4.iterators.TransformIterator;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceWrapper;
import org.apache.sling.api.resource.ValueMap;

/**
 * A ResourceWrapper that filters its descendant resources based on
 * {@code granite:hide} BooleanEL property.
 *
 * 
 * This wrapper needs to be applied to the container resource, such as the page
 * root resource, and the dialog root resource.
 * 
 *
 * 
 * It is also smart enough to handle include component. In that case, if the
 * resource type is {@code granite/ui/components/coral/foundation/include}, the
 * included resource will also be wrapped by this class, allowing the descendant
 * resources of the included resource to use {@code granite:hide} property.
 * 
 *
 * 
 * For example given the following content structure:
 * 
 *
 *  * 
 * + /mycontainer
 *   - sling:resourceType = "my/container"
 *   + item1
 *     - sling:resourceType = "my/item"
 *   + item2
 *     - sling:resourceType = "my/item"
 *     - granite:hide = true
 *   + item3
 *     - sling:resourceType = "my/item"
 *   + item4
 *     - sling:resourceType = "granite/ui/components/coral/foundation/include"
 *     - path = "/mycontainer2"
 *
 * + /mycontainer2
 *   - sling:resourceType = "my/container2"
 *   + item1
 *     - sling:resourceType = "my/item"
 *   + item2
 *     - sling:resourceType = "my/item"
 *     - granite:hide = true
 * 
 * 
 *
 * 
 * Assuming that {@code my/container} resource type implementation uses
 * {@code FilteringResourceWrapper} to wrap its resource ({@code /mycontainer}
 * resource), {@code /mycontainer/item2} and {@code /mycontainer2/item2} will be
 * excluded during traversal transparently, as if they are not there in the
 * first place.
 * 
 */
public class FilteringResourceWrapper extends ResourceWrapper {
    @Nonnull
    private ExpressionResolver expressionResolver;

    @Nonnull
    private SlingHttpServletRequest request;

    public FilteringResourceWrapper(@Nonnull Resource resource, @Nonnull ExpressionResolver expressionResolver,
            @Nonnull SlingHttpServletRequest request) {
        super(resource);
        this.expressionResolver = expressionResolver;
        this.request = request;
    }

    @Override
    public Resource getChild(String relPath) {
        Resource child = super.getChild(relPath);

        if (child == null || !isVisible(child)) {
            return null;
        }

        return new FilteringResourceWrapper(child, expressionResolver, request);
    }

    @Override
    public Iterator listChildren() {
        return new TransformIterator<>(new FilterIterator<>(super.listChildren(), new Predicate() {
            @Override
            public boolean evaluate(Resource o) {
                return isVisible(o);
            }
        }), new Transformer() {
            @SuppressWarnings("null")
            @Override
            public Resource transform(Resource o) {
                return new FilteringResourceWrapper(o, expressionResolver, request);
            }
        });
    }

    @Override
    public Iterable getChildren() {
        return new Iterable() {
            @Override
            public Iterator iterator() {
                return listChildren();
            }
        };
    }

    @Override
    public boolean hasChildren() {
        if (!super.hasChildren()) {
            return false;
        }

        return listChildren().hasNext();
    }

    @Override
    public String getResourceType() {
        if (isResourceType("granite/ui/components/coral/foundation/include")) {
            return "granite/ui/components/coral/foundation/includewrapper";
        }

        return super.getResourceType();
    }

    private boolean isVisible(Resource r) {
        ValueMap vm = r.getValueMap();

        ExpressionHelper ex = new ExpressionHelper(expressionResolver, request);
        return !ex.getBoolean(vm.get("granite:hide", "false"));
    }
}