LeafNode.java 19.8 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
/**
 * $RCSfile: $
 * $Revision: $
 * $Date: $
 *
 * Copyright (C) 2006 Jive Software. All rights reserved.
 *
 * This software is published under the terms of the GNU Public License (GPL),
 * a copy of which is included in this distribution.
 */

package org.jivesoftware.openfire.pubsub;

import org.dom4j.Element;
import org.jivesoftware.util.LocaleUtils;
import org.jivesoftware.util.StringUtils;
import org.xmpp.forms.DataForm;
import org.xmpp.forms.FormField;
import org.xmpp.packet.IQ;
import org.xmpp.packet.JID;
import org.xmpp.packet.Message;

import java.util.*;

/**
 * A type of node that contains published items only. It is NOT a container for
 * other nodes.
 *
 * @author Matt Tucker
 */
public class LeafNode extends Node {

    /**
     * Flag that indicates whether to persist items to storage. Note that when the
     * variable is false then the last published item is the only items being saved
     * to the backend storage.
     */
    private boolean persistPublishedItems;
    /**
     * Maximum number of published items to persist. Note that all nodes are going to persist
     * their published items. The only difference is the number of the last published items
     * to be persisted. Even nodes that are configured to not use persitent items are going
     * to save the last published item.
     */
    private int maxPublishedItems;
    /**
     * The maximum payload size in bytes.
     */
    private int maxPayloadSize;
    /**
     * Flag that indicates whether to send items to new subscribers.
     */
    private boolean sendItemSubscribe;
    /**
     * List of items that were published to the node and that are still active. If the node is
     * not configured to persist items then the last published item will be kept. The list is
     * sorted cronologically.
     */
    protected final List<PublishedItem> publishedItems = new ArrayList<PublishedItem>();
    protected Map<String, PublishedItem> itemsByID = new HashMap<String, PublishedItem>();

    // TODO Add checking of max payload size. Return <not-acceptable> plus a application specific error condition of <payload-too-big/>.

64
    public LeafNode(PubSubService service, CollectionNode parentNode, String nodeID, JID creator) {
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462
        super(service, parentNode, nodeID, creator);
        // Configure node with default values (get them from the pubsub service)
        DefaultNodeConfiguration defaultConfiguration = service.getDefaultNodeConfiguration(true);
        this.persistPublishedItems = defaultConfiguration.isPersistPublishedItems();
        this.maxPublishedItems = defaultConfiguration.getMaxPublishedItems();
        this.maxPayloadSize = defaultConfiguration.getMaxPayloadSize();
        this.sendItemSubscribe = defaultConfiguration.isSendItemSubscribe();
    }

    void configure(FormField field) {
        List<String> values;
        String booleanValue;
        if ("pubsub#persist_items".equals(field.getVariable())) {
            values = field.getValues();
            booleanValue = (values.size() > 0 ? values.get(0) : "1");
            persistPublishedItems = "1".equals(booleanValue);
        }
        else if ("pubsub#max_payload_size".equals(field.getVariable())) {
            values = field.getValues();
            maxPayloadSize = values.size() > 0 ? Integer.parseInt(values.get(0)) : 5120;
        }
        else if ("pubsub#send_item_subscribe".equals(field.getVariable())) {
            values = field.getValues();
            booleanValue = (values.size() > 0 ? values.get(0) : "1");
            sendItemSubscribe = "1".equals(booleanValue);
        }
    }

    void postConfigure(DataForm completedForm) {
        List<String> values;
        if (!persistPublishedItems) {
            // Always save the last published item when not configured to use persistent items
            maxPublishedItems = 1;
        }
        else {
            FormField field = completedForm.getField("pubsub#max_items");
            if (field != null) {
                values = field.getValues();
                maxPublishedItems = values.size() > 0 ? Integer.parseInt(values.get(0)) : 50;
            }
        }
        synchronized (publishedItems) {
            // Remove stored published items based on the new max items
            while (!publishedItems.isEmpty() && publishedItems.size() > maxPublishedItems) {
                PublishedItem removedItem = publishedItems.remove(0);
                itemsByID.remove(removedItem.getID());
                // Add the removed item to the queue of items to delete from the database. The
                // queue is going to be processed by another thread
                service.queueItemToRemove(removedItem);
            }
        }
    }

    protected void addFormFields(DataForm form, boolean isEditing) {
        super.addFormFields(form, isEditing);

        FormField formField = form.addField();
        formField.setVariable("pubsub#send_item_subscribe");
        if (isEditing) {
            formField.setType(FormField.Type.boolean_type);
            formField.setLabel(
                    LocaleUtils.getLocalizedString("pubsub.form.conf.send_item_subscribe"));
        }
        formField.addValue(sendItemSubscribe);

        formField = form.addField();
        formField.setVariable("pubsub#persist_items");
        if (isEditing) {
            formField.setType(FormField.Type.boolean_type);
            formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.persist_items"));
        }
        formField.addValue(persistPublishedItems);

        formField = form.addField();
        formField.setVariable("pubsub#max_items");
        if (isEditing) {
            formField.setType(FormField.Type.text_single);
            formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.max_items"));
        }
        formField.addValue(maxPublishedItems);

        formField = form.addField();
        formField.setVariable("pubsub#max_payload_size");
        if (isEditing) {
            formField.setType(FormField.Type.text_single);
            formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.max_payload_size"));
        }
        formField.addValue(maxPayloadSize);

    }

    protected void deletingNode() {
        synchronized (publishedItems) {
            // Remove stored published items
            while (!publishedItems.isEmpty()) {
                PublishedItem removedItem = publishedItems.remove(0);
                itemsByID.remove(removedItem.getID());
                // Add the removed item to the queue of items to delete from the database. The
                // queue is going to be processed by another thread
                service.queueItemToRemove(removedItem);
            }
        }
    }

    void addPublishedItem(PublishedItem item) {
        synchronized (publishedItems) {
            publishedItems.add(item);
            itemsByID.put(item.getID(), item);
        }
    }

    public int getMaxPayloadSize() {
        return maxPayloadSize;
    }

    public boolean isPersistPublishedItems() {
        return persistPublishedItems;
    }

    public int getMaxPublishedItems() {
        return maxPublishedItems;
    }

    /**
     * Returns true if an item element is required to be included when publishing an
     * item to this node. When an item is included then the item will have an item ID
     * that will be included when sending items to node subscribers.<p>
     *
     * Leaf nodes that are transient and do not deliver payloads with event notifications
     * do not require an item element. If a user tries to publish an item to a node
     * that does not require items then an error will be returned.
     *
     * @return true if an item element is required to be included when publishing an
     *         item to this node.
     */
    public boolean isItemRequired() {
        return isPersistPublishedItems() || isPayloadDelivered();
    }

    /**
     * Publishes the list of items to the node. Event notifications will be sent to subscribers
     * for the new published event. The published event may or may not include an item. When the
     * node is not persistent and does not require payloads then an item is not going to be created
     * nore included in the event notification.<p>
     *
     * When an affiliate has many subscriptions to the node, the affiliate will get a
     * notification for each set of items that affected the same list of subscriptions.<p>
     *
     * When an item is included in the published event then a new {@link PublishedItem} is
     * going to be created and added to the list of published item. Each published item will
     * have a unique ID in the node scope. The new published item will be added to the end
     * of the published list to keep the cronological order. When the max number of published
     * items is exceeded then the oldest published items will be removed.<p>
     *
     * For performance reasons the newly added published items and the deleted items (if any)
     * are saved to the database using a background thread. Sending event notifications to
     * node subscribers may also use another thread to ensure good performance.<p>
     *
     * @param publisher the full JID of the user that sent the new published event.
     * @param itemElements list of dom4j elements that contain info about the published items.
     */
    public void publishItems(JID publisher, List<Element> itemElements) {
        List<PublishedItem> newPublishedItems = new ArrayList<PublishedItem>();
        if (isItemRequired()) {
            String itemID;
            Element payload;
            PublishedItem newItem;
            for (Element item : itemElements) {
                itemID = item.attributeValue("id");
                List entries = item.elements();
                payload = entries.isEmpty() ? null : (Element) entries.get(0);
                // Create a published item from the published data and add it to the node and the db
                synchronized (publishedItems) {
                    // Make sure that the published item has an ID and that it's unique in the node
                    if (itemID == null) {
                        itemID = StringUtils.randomString(15);
                    }
                    while (itemsByID.get(itemID) != null) {
                        itemID = StringUtils.randomString(15);
                    }

                    // Create a new published item
                    newItem = new PublishedItem(this, publisher, itemID, new Date());
                    newItem.setPayload(payload);
                    // Add the new item to the list of published items
                    newPublishedItems.add(newItem);

                    // Add the published item to the list of items to persist (using another thread)
                    // but check that we don't exceed the limit. Remove oldest items if required.
                    while (!publishedItems.isEmpty() && publishedItems.size() >= maxPublishedItems)
                    {
                        PublishedItem removedItem = publishedItems.remove(0);
                        itemsByID.remove(removedItem.getID());
                        // Add the removed item to the queue of items to delete from the database. The
                        // queue is going to be processed by another thread
                        service.queueItemToRemove(removedItem);
                    }
                    addPublishedItem(newItem);
                    // Add the new published item to the queue of items to add to the database. The
                    // queue is going to be processed by another thread
                    service.queueItemToAdd(newItem);
                }
            }
        }

        // Build event notification packet to broadcast to subscribers
        Message message = new Message();
        Element event = message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
        // Broadcast event notification to subscribers and parent node subscribers
        Set<NodeAffiliate> affiliatesToNotify = new HashSet<NodeAffiliate>(affiliates);
        // Get affiliates that are subscribed to a parent in the hierarchy of parent nodes
        for (CollectionNode parentNode : getParents()) {
            for (NodeSubscription subscription : parentNode.getSubscriptions()) {
                affiliatesToNotify.add(subscription.getAffiliate());
            }
        }
        // TODO Use another thread for this (if # of subscribers is > X)????
        for (NodeAffiliate affiliate : affiliatesToNotify) {
            affiliate.sendPublishedNotifications(message, event, this, newPublishedItems);
        }
    }

    /**
     * Deletes the list of published items from the node. Event notifications may be sent to
     * subscribers for the deleted items. When an affiliate has many subscriptions to the node,
     * the affiliate will get a notification for each set of items that affected the same list
     * of subscriptions.<p>
     *
     * For performance reasons the deleted published items are saved to the database
     * using a background thread. Sending event notifications to node subscribers may
     * also use another thread to ensure good performance.<p>
     *
     * @param toDelete list of items that were deleted from the node.
     */
    public void deleteItems(List<PublishedItem> toDelete) {
        synchronized (publishedItems) {
            for (PublishedItem item : toDelete) {
                // Remove items to delete from memory
                publishedItems.remove(item);
                // Update fast look up cache of published items
                itemsByID.remove(item.getID());
            }
        }
        // Remove deleted items from the database
        for (PublishedItem item : toDelete) {
            service.queueItemToRemove(item);
        }
        if (isNotifiedOfRetract()) {
            // Broadcast notification deletion to subscribers
            // Build packet to broadcast to subscribers
            Message message = new Message();
            Element event =
                    message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
            // Send notification that items have been deleted to subscribers and parent node
            // subscribers
            Set<NodeAffiliate> affiliatesToNotify = new HashSet<NodeAffiliate>(affiliates);
            // Get affiliates that are subscribed to a parent in the hierarchy of parent nodes
            for (CollectionNode parentNode : getParents()) {
                for (NodeSubscription subscription : parentNode.getSubscriptions()) {
                    affiliatesToNotify.add(subscription.getAffiliate());
                }
            }
            // TODO Use another thread for this (if # of subscribers is > X)????
            for (NodeAffiliate affiliate : affiliatesToNotify) {
                affiliate.sendDeletionNotifications(message, event, this, toDelete);
            }
        }
    }

    /**
     * Sends an IQ result with the list of items published to the node. Item ID and payload
     * may be included in the result based on the node configuration.
     *
     * @param originalRequest the IQ packet sent by a subscriber (or anyone) to get the node items.
     * @param publishedItems the list of published items to send to the subscriber.
     * @param forceToIncludePayload true if the item payload should be include if one exists. When
     *        false the decision is up to the node.
     */
    void sendPublishedItems(IQ originalRequest, List<PublishedItem> publishedItems,
            boolean forceToIncludePayload) {
        IQ result = IQ.createResultIQ(originalRequest);
        Element childElement = originalRequest.getChildElement().createCopy();
        result.setChildElement(childElement);
        Element items = childElement.element("items");
        for (PublishedItem publishedItem : publishedItems) {
            Element item = items.addElement("item");
            if (isItemRequired()) {
                item.addAttribute("id", publishedItem.getID());
            }
            if ((forceToIncludePayload || isPayloadDelivered()) &&
                    publishedItem.getPayload() != null) {
                item.add(publishedItem.getPayload().createCopy());
            }
        }
        // Send the result
        service.send(result);
    }

    public PublishedItem getPublishedItem(String itemID) {
        if (!isItemRequired()) {
            return null;
        }
        synchronized (publishedItems) {
            return itemsByID.get(itemID);
        }
    }

    public List<PublishedItem> getPublishedItems() {
        synchronized (publishedItems) {
            return Collections.unmodifiableList(publishedItems);
        }
    }

    public List<PublishedItem> getPublishedItems(int recentItems) {
        synchronized (publishedItems) {
            int size = publishedItems.size();
            if (recentItems > size) {
                // User requested more items than the one the node has so return the current list
                return Collections.unmodifiableList(publishedItems);
            }
            else {
                // Return the number of recent items the user requested
                List<PublishedItem> recent = publishedItems.subList(size - recentItems, size);
                return new ArrayList<PublishedItem>(recent);
            }
        }
    }

    public PublishedItem getLastPublishedItem() {
        synchronized (publishedItems) {
            if (publishedItems.isEmpty()) {
                return null;
            }
            return publishedItems.get(publishedItems.size()-1);
        }
    }

    /**
     * Returns true if the last published item is going to be sent to new subscribers.
     *
     * @return true if the last published item is going to be sent to new subscribers.
     */
    public boolean isSendItemSubscribe() {
        return sendItemSubscribe;
    }

    void setMaxPayloadSize(int maxPayloadSize) {
        this.maxPayloadSize = maxPayloadSize;
    }

    void setPersistPublishedItems(boolean persistPublishedItems) {
        this.persistPublishedItems = persistPublishedItems;
    }

    void setMaxPublishedItems(int maxPublishedItems) {
        this.maxPublishedItems = maxPublishedItems;
    }

    void setSendItemSubscribe(boolean sendItemSubscribe) {
        this.sendItemSubscribe = sendItemSubscribe;
    }

    /**
     * Purges items that were published to the node. Only owners can request this operation.
     * This operation is only available for nodes configured to store items in the database. All
     * published items will be deleted with the exception of the last published item.
     */
    public void purge() {
        List<PublishedItem> toDelete = null;
        // Calculate items to delete
        synchronized (publishedItems) {
            if (publishedItems.size() > 1) {
                // Remove all items except the last one
                toDelete = new ArrayList<PublishedItem>(
                        publishedItems.subList(0, publishedItems.size() - 1));
                // Remove items to delete from memory
                publishedItems.removeAll(toDelete);
                // Update fast look up cache of published items
                itemsByID = new HashMap<String, PublishedItem>();
                itemsByID.put(publishedItems.get(0).getID(), publishedItems.get(0));
            }
        }
        if (toDelete != null) {
            // Delete purged items from the database
            for (PublishedItem item : toDelete) {
                service.queueItemToRemove(item);
            }
            // Broadcast purge notification to subscribers
            // Build packet to broadcast to subscribers
            Message message = new Message();
            Element event = message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
            Element items = event.addElement("purge");
            items.addAttribute("node", nodeID);
            // Send notification that the node configuration has changed
            broadcastNodeEvent(message, false);
        }
    }
}