io.wcm.caravan.pipeline.extensions.hal.filter.ReportHalResourceFilters.java Source code

Introduction

Here is the source code for io.wcm.caravan.pipeline.extensions.hal.filter.ReportHalResourceFilters.java

Source

/*
 * #%L
 * wcm.io
 * %%
 * Copyright (C) 2015 wcm.io
 * %%
 * 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.
 * #L%
 */
package io.wcm.caravan.pipeline.extensions.hal.filter;

import java.util.List;
import java.util.stream.Stream;

import org.apache.commons.lang3.StringUtils;

import com.fasterxml.jackson.databind.node.ArrayNode;
import com.google.common.collect.Lists;

import io.wcm.caravan.hal.resource.HalResource;

/**
 * Collection of common reporting {@link HalResourcePredicate}s which write negative predicate results into a HAL
 * document.
 */
public final class ReportHalResourceFilters {

    private ReportHalResourceFilters() {
        // nothing to do
    }

    /**
     * Executes all delegated filters and creates a report with error messages for each failed filter. If there are
     * negative predicate results, all further predicates still get executed.
     */
    public static HalResourcePredicate all(HalResource report, HalResourcePredicate... delegates) {

        return new HalResourcePredicate() {

            @Override
            public String getId() {
                List<String> ids = Stream.of(delegates).map(matcher -> matcher.getId())
                        .collect(java.util.stream.Collectors.toList());
                return "ALL(" + StringUtils.join(ids, '+') + ")";
            }

            @Override
            public boolean apply(HalPath halPath, HalResource hal) {

                List<String> errors = Stream.of(delegates).filter(delegate -> !delegate.apply(halPath, hal))
                        .map(delegate -> delegate.getId()).collect(java.util.stream.Collectors.toList());

                if (!errors.isEmpty()) {
                    report.addEmbedded("item", createReport(halPath, hal, errors));
                }
                return errors.isEmpty();

            }

        };

    }

    /**
     * @param report Report to write to
     * @param delegate Delegated filter
     */
    public static HalResourcePredicate report(HalResource report, HalResourcePredicate delegate) {

        return new HalResourcePredicate() {

            @Override
            public String getId() {
                return delegate.getId();
            }

            @Override
            public boolean apply(HalPath halPath, HalResource hal) {

                if (!delegate.apply(halPath, hal)) {
                    report.addEmbedded("item", createReport(halPath, hal, Lists.newArrayList(delegate.getId())));
                    return false;
                }
                return true;

            }

        };

    }

    private static HalResource createReport(HalPath halPath, HalResource hal, List<String> errors) {

        HalResource filterReport = new HalResource(hal.getLink().getHref());
        filterReport.getModel().put("halPath", halPath.toString());
        ArrayNode errorContainer = filterReport.getModel().putArray("errors");
        for (String error : errors) {
            errorContainer.add(error);
        }

        filterReport.getModel().set("copy", hal.getModel().deepCopy());

        return filterReport;

    }

}