001 package de.deepamehta.plugins.time;
002
003 import de.deepamehta.plugins.time.service.TimeService;
004
005 import de.deepamehta.core.Association;
006 import de.deepamehta.core.DeepaMehtaObject;
007 import de.deepamehta.core.Topic;
008 import de.deepamehta.core.model.AssociationModel;
009 import de.deepamehta.core.model.CompositeValueModel;
010 import de.deepamehta.core.model.TopicModel;
011 import de.deepamehta.core.osgi.PluginActivator;
012 import de.deepamehta.core.service.ClientState;
013 import de.deepamehta.core.service.Directives;
014 import de.deepamehta.core.service.event.PostCreateAssociationListener;
015 import de.deepamehta.core.service.event.PostCreateTopicListener;
016 import de.deepamehta.core.service.event.PostUpdateAssociationListener;
017 import de.deepamehta.core.service.event.PostUpdateTopicListener;
018 import de.deepamehta.core.service.event.PreSendAssociationListener;
019 import de.deepamehta.core.service.event.PreSendTopicListener;
020 import de.deepamehta.core.service.event.ServiceResponseFilterListener;
021
022 // ### TODO: hide Jersey internals. Move to JAX-RS 2.0.
023 import com.sun.jersey.spi.container.ContainerResponse;
024
025 import javax.ws.rs.GET;
026 import javax.ws.rs.PUT;
027 import javax.ws.rs.POST;
028 import javax.ws.rs.DELETE;
029 import javax.ws.rs.HeaderParam;
030 import javax.ws.rs.Path;
031 import javax.ws.rs.PathParam;
032 import javax.ws.rs.Produces;
033 import javax.ws.rs.Consumes;
034 import javax.ws.rs.core.MultivaluedMap;
035
036 import java.text.DateFormat;
037 import java.text.SimpleDateFormat;
038 import java.util.Collection;
039 import java.util.Date;
040 import java.util.Locale;
041 import java.util.TimeZone;
042 import java.util.logging.Logger;
043
044
045
046 @Path("/time")
047 @Consumes("application/json")
048 @Produces("application/json")
049 public class TimePlugin extends PluginActivator implements TimeService, PostCreateTopicListener,
050 PostCreateAssociationListener,
051 PostUpdateTopicListener,
052 PostUpdateAssociationListener,
053 PreSendTopicListener,
054 PreSendAssociationListener,
055 ServiceResponseFilterListener {
056
057 // ------------------------------------------------------------------------------------------------------- Constants
058
059 private static String PROP_URI_CREATED = "dm4.time.created";
060 private static String PROP_URI_MODIFIED = "dm4.time.modified";
061
062 private static String HEADER_LAST_MODIFIED = "Last-Modified";
063
064 // ---------------------------------------------------------------------------------------------- Instance Variables
065
066 private DateFormat rfc2822;
067
068 private Logger logger = Logger.getLogger(getClass().getName());
069
070 // -------------------------------------------------------------------------------------------------- Public Methods
071
072
073
074 // **********************************
075 // *** TimeService Implementation ***
076 // **********************************
077
078
079
080 // === Timestamps ===
081
082 // Note: the timestamp getters must return 0 as default. Before we used -1 but Jersey's evaluatePreconditions()
083 // does not work as expected when called with a negative value which is not dividable by 1000.
084
085 @Override
086 public long getCreationTime(DeepaMehtaObject object) {
087 return object.hasProperty(PROP_URI_CREATED) ? (Long) object.getProperty(PROP_URI_CREATED) : 0;
088 }
089
090 @Override
091 public long getModificationTime(DeepaMehtaObject object) {
092 return object.hasProperty(PROP_URI_MODIFIED) ? (Long) object.getProperty(PROP_URI_MODIFIED) : 0;
093 }
094
095
096
097 // === Retrieval ===
098
099 @GET
100 @Path("/from/{from}/to/{to}/topics/created")
101 @Override
102 public Collection<Topic> getTopicsByCreationTime(@PathParam("from") long from,
103 @PathParam("to") long to) {
104 return dms.getTopicsByPropertyRange(PROP_URI_CREATED, from, to);
105 }
106
107 @GET
108 @Path("/from/{from}/to/{to}/topics/modified")
109 @Override
110 public Collection<Topic> getTopicsByModificationTime(@PathParam("from") long from,
111 @PathParam("to") long to) {
112 return dms.getTopicsByPropertyRange(PROP_URI_MODIFIED, from, to);
113 }
114
115 @GET
116 @Path("/from/{from}/to/{to}/assocs/created")
117 @Override
118 public Collection<Association> getAssociationsByCreationTime(@PathParam("from") long from,
119 @PathParam("to") long to) {
120 return dms.getAssociationsByPropertyRange(PROP_URI_CREATED, from, to);
121 }
122
123 @GET
124 @Path("/from/{from}/to/{to}/assocs/modified")
125 @Override
126 public Collection<Association> getAssociationsByModificationTime(@PathParam("from") long from,
127 @PathParam("to") long to) {
128 return dms.getAssociationsByPropertyRange(PROP_URI_MODIFIED, from, to);
129 }
130
131
132
133 // ****************************
134 // *** Hook Implementations ***
135 // ****************************
136
137
138
139 @Override
140 public void init() {
141 // create the date format used in HTTP date/time headers, see:
142 // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.3
143 rfc2822 = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.ENGLISH);
144 rfc2822.setTimeZone(TimeZone.getTimeZone("GMT+00:00"));
145 ((SimpleDateFormat) rfc2822).applyPattern("EEE, dd MMM yyyy HH:mm:ss 'GMT'");
146 }
147
148
149
150 // ********************************
151 // *** Listener Implementations ***
152 // ********************************
153
154
155
156 @Override
157 public void postCreateTopic(Topic topic, ClientState clientState, Directives directives) {
158 storeTimestamps(topic);
159 }
160
161 @Override
162 public void postCreateAssociation(Association assoc, ClientState clientState, Directives directives) {
163 storeTimestamps(assoc);
164 }
165
166 @Override
167 public void postUpdateTopic(Topic topic, TopicModel newModel, TopicModel oldModel, ClientState clientState,
168 Directives directives) {
169 storeTimestamp(topic);
170 }
171
172 @Override
173 public void postUpdateAssociation(Association assoc, AssociationModel oldModel, ClientState clientState,
174 Directives directives) {
175 storeTimestamp(assoc);
176 }
177
178 // ---
179
180 @Override
181 public void preSendTopic(Topic topic, ClientState clientState) {
182 enrichWithTimestamp(topic);
183 }
184
185 @Override
186 public void preSendAssociation(Association assoc, ClientState clientState) {
187 enrichWithTimestamp(assoc);
188 }
189
190 // ---
191
192 @Override
193 public void serviceResponseFilter(ContainerResponse response) {
194 DeepaMehtaObject object = responseObject(response);
195 if (object != null) {
196 long modified = enrichWithTimestamp(object);
197 setLastModifiedHeader(response, modified);
198 }
199 }
200
201
202
203 // ------------------------------------------------------------------------------------------------- Private Methods
204
205 private void storeTimestamps(DeepaMehtaObject object) {
206 long time = System.currentTimeMillis();
207 storeCreationTime(object, time);
208 storeModificationTime(object, time);
209 }
210
211 private void storeTimestamp(DeepaMehtaObject object) {
212 long time = System.currentTimeMillis();
213 storeModificationTime(object, time);
214 }
215
216 // ---
217
218 private void storeCreationTime(DeepaMehtaObject object, long time) {
219 storeTime(object, PROP_URI_CREATED, time);
220 }
221
222 private void storeModificationTime(DeepaMehtaObject object, long time) {
223 storeTime(object, PROP_URI_MODIFIED, time);
224 }
225
226 // ---
227
228 private void storeTime(DeepaMehtaObject object, String propUri, long time) {
229 object.setProperty(propUri, time, true); // addToIndex=true
230 }
231
232 // ===
233
234 // ### FIXME: copy in CachingPlugin
235 private DeepaMehtaObject responseObject(ContainerResponse response) {
236 Object entity = response.getEntity();
237 return entity instanceof DeepaMehtaObject ? (DeepaMehtaObject) entity : null;
238 }
239
240 private long enrichWithTimestamp(DeepaMehtaObject object) {
241 long created = getCreationTime(object);
242 long modified = getModificationTime(object);
243 CompositeValueModel comp = object.getCompositeValue().getModel();
244 comp.put(PROP_URI_CREATED, created);
245 comp.put(PROP_URI_MODIFIED, modified);
246 return modified;
247 }
248
249 // ---
250
251 private void setLastModifiedHeader(ContainerResponse response, long time) {
252 setHeader(response, HEADER_LAST_MODIFIED, rfc2822.format(time));
253 }
254
255 // ### FIXME: copy in CachingPlugin
256 private void setHeader(ContainerResponse response, String header, String value) {
257 MultivaluedMap headers = response.getHttpHeaders();
258 //
259 if (headers.containsKey(header)) {
260 throw new RuntimeException("Response already has a \"" + header + "\" header");
261 }
262 //
263 headers.putSingle(header, value);
264 }
265 }