001/*
002 * (C) Copyright 2015 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nicolas Chapurlat <nchapurlat@nuxeo.com>
018 */
019
020package org.nuxeo.ecm.core.io.marshallers.json.enrichers;
021
022import static org.nuxeo.ecm.core.io.registry.reflect.Instantiations.SINGLETON;
023import static org.nuxeo.ecm.core.io.registry.reflect.Priorities.REFERENCE;
024
025import java.io.IOException;
026
027import org.nuxeo.ecm.core.api.DocumentModel;
028import org.nuxeo.ecm.core.api.DocumentModelList;
029import org.nuxeo.ecm.core.io.marshallers.json.document.DocumentModelListJsonWriter;
030import org.nuxeo.ecm.core.io.registry.context.RenderingContext.SessionWrapper;
031import org.nuxeo.ecm.core.io.registry.reflect.Setup;
032
033import com.fasterxml.jackson.core.JsonGenerator;
034
035/**
036 * Enrich {@link DocumentModel} Json.
037 * <p>
038 * Add document children (list of document) as json attachment.
039 * </p>
040 * <p>
041 * Enable if parameter enrichers-document=children is present.
042 * </p>
043 * <p>
044 * Format is:
045 *
046 * <pre>
047 * {@code
048 * {
049 *   "entity-type":"document",
050 *   ...
051 *   "contextParameters": {
052 *     "children": { see {@link DocumentModelListJsonWriter} for format }
053 *   }
054 * }
055 * </pre>
056 *
057 * </p>
058 *
059 * @since 7.2
060 */
061@Setup(mode = SINGLETON, priority = REFERENCE)
062public class ChildrenJsonEnricher extends AbstractJsonEnricher<DocumentModel> {
063
064    public static final String NAME = "children";
065
066    public ChildrenJsonEnricher() {
067        super(NAME);
068    }
069
070    @Override
071    public void write(JsonGenerator jg, DocumentModel document) throws IOException {
072        DocumentModelList children = null;
073        try (SessionWrapper wrapper = ctx.getSession(document)) {
074            children = wrapper.getSession().getChildren(document.getRef());
075        }
076        jg.writeFieldName(NAME);
077        writeEntity(children, jg);
078    }
079
080}