SerializationUtil.java

/**
 * Copyright 2008 The University of North Carolina at Chapel Hill
 *
 * 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 edu.unc.lib.dl.ui.util;

import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import edu.unc.lib.dl.acl.util.AccessGroupSet;
import edu.unc.lib.dl.search.solr.model.BriefObjectMetadata;
import edu.unc.lib.dl.search.solr.model.CutoffFacet;
import edu.unc.lib.dl.search.solr.model.HierarchicalBrowseResultResponse;
import edu.unc.lib.dl.search.solr.model.HierarchicalFacetNode;
import edu.unc.lib.dl.search.solr.model.SearchResultResponse;
import edu.unc.lib.dl.search.solr.util.SearchSettings;
import edu.unc.lib.dl.search.solr.util.SolrSettings;
import edu.unc.lib.dl.ui.util.ApplicationPathSettings;
import edu.unc.lib.dl.util.DateTimeUtil;

public class SerializationUtil {
	private static final Logger log = LoggerFactory.getLogger(SerializationUtil.class);

	private static ObjectMapper jsonMapper = new ObjectMapper();
	static {
		jsonMapper.setSerializationInclusion(Inclusion.NON_NULL);
	}
	private static ApplicationPathSettings applicationPathSettings;
	private static SearchSettings searchSettings;
	private static SolrSettings solrSettings;
	
	public static String structureToJSON(HierarchicalBrowseResultResponse response, AccessGroupSet groups) {
		Map<String, Object> result = new HashMap<String, Object>();
		result.put("root", structureStep(response.getRootNode(), groups));
		return objectToJSON(result);
	}

	private static Map<String, Object> structureStep(HierarchicalBrowseResultResponse.ResultNode node,
			AccessGroupSet groups) {
		Map<String, Object> entryMap = new HashMap<String, Object>();
		Map<String, Object> metadataMap = metadataToMap(node.getMetadata(), groups);
		entryMap.put("entry", metadataMap);
		if (node.getMetadata().getAncestorNames() != null
				&& (node.getMetadata().getAncestorPath() == null || node.getMetadata().getAncestorPath().size() == 0))
			entryMap.put("isTopLevel", "true");

		if (node.getChildren().size() > 0) {
			List<Object> childrenList = new ArrayList<Object>(node.getChildren().size());
			entryMap.put("children", childrenList);
			for (int i = 0; i < node.getChildren().size(); i++) {
				childrenList.add(structureStep(node.getChildren().get(i), groups));
			}
		}
		return entryMap;
	}

	public static String resultsToJSON(SearchResultResponse resultResponse, AccessGroupSet groups) {
		StringBuilder result = new StringBuilder();
		result.append('[');
		boolean firstEntry = true;
		for (BriefObjectMetadata metadata : resultResponse.getResultList()) {
			if (firstEntry)
				firstEntry = false;
			else
				result.append(',');
			result.append(metadataToJSON(metadata, groups));
		}
		result.append(']');
		return result.toString();
	}

	public static List<Map<String, Object>> resultsToList(SearchResultResponse resultResponse, AccessGroupSet groups) {
		List<Map<String, Object>> result = new ArrayList<Map<String, Object>>(resultResponse.getResultList().size());

		for (BriefObjectMetadata metadata : resultResponse.getResultList()) {
			result.add(metadataToMap(metadata, groups));
		}

		return result;
	}

	public static Map<String, Object> metadataToMap(BriefObjectMetadata metadata, AccessGroupSet groups) {
		Map<String, Object> result = new HashMap<String, Object>();
		if (metadata.getId() != null) {
			result.put("id", metadata.getId());
			result.put("uri", applicationPathSettings.getApiRecordPath() + metadata.getId());
		}

		if (metadata.getLabel() != null)
			result.put("label", metadata.getLabel());

		if (metadata.getTitle() != null)
			result.put("title", metadata.getTitle());

		if (metadata.get_version_() != null)
			result.put("_version_", metadata.get_version_());

		if (metadata.getStatus() != null && metadata.getStatus().size() > 0)
			result.put("status", metadata.getStatus());

		if (metadata.getContentStatus() != null && metadata.getContentStatus().size() > 0)
			result.put("contentStatus", metadata.getContentStatus());

		if (metadata.getSubject() != null)
			result.put("subject", metadata.getSubject());

		if (metadata.getResourceType() != null)
			result.put("type", metadata.getResourceType());

		if (metadata.getContentModel() != null && metadata.getContentModel().size() > 0)
			result.put("model", metadata.getContentModel());

		if (metadata.getCreator() != null)
			result.put("creator", metadata.getCreator());

		if (metadata.getDatastream() != null)
			result.put("datastream", metadata.getDatastream());

		if (metadata.getIdentifier() != null)
			result.put("identifier", metadata.getIdentifier());

		if (metadata.getAncestorPathFacet() != null) {
			result.put("ancestorPath", cutoffFacetToMap(metadata.getAncestorPathFacet()));
			result.put("objectPath", metadata.getObjectPath().getEntries());
		}

		if (metadata.getAncestorNames() != null)
			result.put("ancestorNames", metadata.getAncestorNames());

		if (metadata.getTags() != null)
			result.put("tags", metadata.getTags());

		if (metadata.getIsPart() != null) {
			result.put("isPart", metadata.getIsPart());
		}

		if (metadata.getRollup() != null) {
			result.put("rollup", metadata.getRollup());
		}

		if (metadata.getCountMap() != null && metadata.getCountMap().size() > 0)
			result.put("counts", metadata.getCountMap());

		try {
			if (metadata.getDateAdded() != null) {
				String dateAdded = DateTimeUtil.formatDateToUTC(metadata.getDateAdded());
				result.put("added", dateAdded);
			}
			if (metadata.getDateUpdated() != null) {
				String dateUpdated = DateTimeUtil.formatDateToUTC(metadata.getDateUpdated());
				result.put("updated", dateUpdated);
			}
		} catch (ParseException e) {
			log.debug("Failed to parse date field for " + metadata.getId(), e);
		}

		if (metadata.getDateCreated() != null)
			result.put("created", metadata.getDateCreated());
		
		if (metadata.getTimestamp() != null) {
			result.put("timestamp", metadata.getTimestamp());
		}

		if (groups != null && metadata.getAccessControlBean() != null)
			result.put("permissions", metadata.getAccessControlBean().getPermissionsByGroups(groups));

		if (metadata.getDynamicFields() != null) {
			Iterator<Entry<String, Object>> fieldIt = metadata.getDynamicFields().entrySet().iterator();
			while (fieldIt.hasNext()) {
				Entry<String, Object> entry = fieldIt.next();
				// Translate the solr field back into the query parameter name
				String fieldKey = solrSettings.getFieldKey(entry.getKey());
				String paramName = searchSettings.getSearchFieldParam(fieldKey);
				if (paramName != null)
					result.put(paramName, entry.getValue());
			}
		}

		return result;
	}

	private static Object cutoffFacetToMap(CutoffFacet facet) {
		List<Map<String, String>> result = new ArrayList<Map<String,String>>(facet.getFacetNodes().size());
		for (HierarchicalFacetNode node : facet.getFacetNodes()) {
			Map<String, String> nodeEntry = new HashMap<String, String>();
			nodeEntry.put("id", node.getSearchKey());
			nodeEntry.put("title", node.getDisplayValue());
			result.add(nodeEntry);
		}
		return result;
	}

	public static String metadataToJSON(BriefObjectMetadata metadata, AccessGroupSet groups) {
		try {
			return jsonMapper.writeValueAsString(metadataToMap(metadata, groups));
		} catch (JsonGenerationException e) {
			log.error("Unable to serialize object " + metadata.getId() + " to json", e);
		} catch (JsonMappingException e) {
			log.error("Unable to serialize object " + metadata.getId() + " to json", e);
		} catch (IOException e) {
			log.error("Unable to serialize object " + metadata.getId() + " to json", e);
		}
		return null;
	}

	public static String objectToJSON(Object object) {
		try {
			return jsonMapper.writeValueAsString(object);
		} catch (JsonGenerationException e) {
			log.error("Unable to serialize object of type " + object.getClass().getName() + " to json", e);
		} catch (JsonMappingException e) {
			log.error("Unable to serialize object of type " + object.getClass().getName() + " to json", e);
		} catch (IOException e) {
			log.error("Unable to serialize object of type " + object.getClass().getName() + " to json", e);
		}
		return "";
	}

	public static void injectSettings(ApplicationPathSettings applicationPathSettings, SearchSettings searchSettings, SolrSettings solrSettings) {
		SerializationUtil.applicationPathSettings = applicationPathSettings;
		SerializationUtil.searchSettings = searchSettings;
		SerializationUtil.solrSettings = solrSettings;
	}
}