1/*
2 Copyright (c) 2007 Tobias Koenig <tokoe@kde.org>
3
4 This library is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Library General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or (at your
7 option) any later version.
8
9 This library is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
12 License for more details.
13
14 You should have received a copy of the GNU Library General Public License
15 along with this library; see the file COPYING.LIB. If not, write to the
16 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 02110-1301, USA.
18*/
19
20#ifndef AKONADI_ITEMSYNC_H
21#define AKONADI_ITEMSYNC_H
22
23#include "akonadi_export.h"
24
25#include <akonadi/item.h>
26#include <akonadi/job.h>
27
28namespace Akonadi {
29
30class Collection;
31class ItemFetchScope;
32class ItemSyncPrivate;
33
34/**
35 * @short Syncs between items known to a client (usually a resource) and the Akonadi storage.
36 *
37 * Remote Id must only be set by the resource storing the item, other clients
38 * should leave it empty, since the resource responsible for the target collection
39 * will be notified about the addition and then create a suitable remote Id.
40 *
41 * There are two different forms of ItemSync usage:
42 * - Full-Sync: meaning the client provides all valid items, i.e. any item not
43 * part of the list but currently stored in Akonadi will be removed
44 * - Incremental-Sync: meaning the client provides two lists, one for items which
45 * are new or modified and one for items which should be removed. Any item not
46 * part of either list but currently stored in Akonadi will not be changed.
47 *
48 * @note This is provided for convenience to implement "save all" like behavior,
49 * however it is strongly recommended to use single item jobs whenever
50 * possible, e.g. ItemCreateJob, ItemModifyJob and ItemDeleteJob
51 *
52 * @author Tobias Koenig <tokoe@kde.org>
53 */
54class AKONADI_EXPORT ItemSync : public Job
55{
56 Q_OBJECT
57
58public:
59 /**
60 * Creates a new item synchronizer.
61 *
62 * @param collection The collection we are syncing.
63 * @param parent The parent object.
64 */
65 explicit ItemSync(const Collection &collection, QObject *parent = 0);
66
67 /**
68 * Destroys the item synchronizer.
69 */
70 ~ItemSync();
71
72 /**
73 * Sets the full item list for the collection.
74 *
75 * Usually the result of a full item listing.
76 *
77 * @warning If the client using this is a resource, all items must have
78 * a valid remote identifier.
79 *
80 * @param items A list of items.
81 */
82 void setFullSyncItems(const Item::List &items);
83
84 /**
85 * Set the amount of items which you are going to return in total
86 * by using the setFullSyncItems()/setIncrementalSyncItems() methods.
87 *
88 * @warning By default the item sync will automatically end once
89 * sufficient items have been provided.
90 * To disable this use setDisableAutomaticDeliveryDone
91 *
92 * @see setDisableAutomaticDeliveryDone
93 * @param amount The amount of items in total.
94 */
95 void setTotalItems(int amount);
96
97 /**
98 Enable item streaming. Item streaming means that the items delivered by setXItems() calls
99 are delivered in chunks and you manually indicate when all items have been delivered
100 by calling deliveryDone().
101 @param enable @c true to enable item streaming
102 */
103 void setStreamingEnabled(bool enable);
104
105 /**
106 Notify ItemSync that all remote items have been delivered.
107 Only call this in streaming mode.
108 */
109 void deliveryDone();
110
111 /**
112 * Sets the item lists for incrementally syncing the collection.
113 *
114 * Usually the result of an incremental remote item listing.
115 *
116 * @warning If the client using this is a resource, all items must have
117 * a valid remote identifier.
118 *
119 * @param changedItems A list of items added or changed by the client.
120 * @param removedItems A list of items deleted by the client.
121 */
122 void setIncrementalSyncItems(const Item::List &changedItems,
123 const Item::List &removedItems);
124
125 /**
126 * Sets the item fetch scope.
127 *
128 * The ItemFetchScope controls how much of an item's data is fetched
129 * from the server, e.g. whether to fetch the full item payload or
130 * only meta data.
131 *
132 * @param fetchScope The new scope for item fetch operations.
133 *
134 * @see fetchScope()
135 */
136 void setFetchScope(ItemFetchScope &fetchScope);
137
138 /**
139 * Returns the item fetch scope.
140 *
141 * Since this returns a reference it can be used to conveniently modify the
142 * current scope in-place, i.e. by calling a method on the returned reference
143 * without storing it in a local variable. See the ItemFetchScope documentation
144 * for an example.
145 *
146 * @return a reference to the current item fetch scope
147 *
148 * @see setFetchScope() for replacing the current item fetch scope
149 */
150 ItemFetchScope &fetchScope();
151
152 /**
153 * Aborts the sync process and rolls back all not yet committed transactions.
154 * Use this if an external error occurred during the sync process (such as the
155 * user canceling it).
156 * @since 4.5
157 */
158 void rollback();
159
160 /**
161 * Transaction mode used by ItemSync.
162 * @since 4.6
163 */
164 enum TransactionMode {
165 SingleTransaction, ///< Use a single transaction for the entire sync process (default), provides maximum consistency ("all or nothing") and best performance
166 MultipleTransactions, ///< Use one transaction per chunk of delivered items, good compromise between the other two when using streaming
167 NoTransaction ///< Use no transaction at all, provides highest responsiveness (might therefore feel faster even when actually taking slightly longer), no consistency guaranteed (can fail anywhere in the sync process)
168 };
169
170 /**
171 * Set the transaction mode to use for this sync.
172 * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
173 * @param mode the transaction mode to use
174 * @since 4.6
175 */
176 void setTransactionMode(TransactionMode mode);
177
178 /**
179 * Minimum number of items required to start processing in streaming mode.
180 * When MultipleTransactions is used, one transaction per batch will be created.
181 *
182 * @see setBatchSize()
183 * @since 4.14
184 */
185 int batchSize() const;
186
187 /**
188 * Set the batch size.
189 *
190 * The default is 10.
191 *
192 * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
193 * @see batchSize()
194 * @since 4.14
195 */
196 void setBatchSize(int);
197
198 /**
199 * Disables the automatic completion of the item sync,
200 * based on the number of delivered items.
201 *
202 * This ensures that the item sync only finishes once deliveryDone()
203 * is called, while still making it possible to use the progress
204 * reporting of the ItemSync.
205 *
206 * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
207 * @see setTotalItems
208 * @since 4.14
209 */
210 void setDisableAutomaticDeliveryDone(bool disable);
211
212Q_SIGNALS:
213 /**
214 * Signals the resource that new items can be delivered.
215 * @param remainingBatchSize the number of items required to complete the batch (typically the same as batchSize())
216 *
217 * @since 4.14
218 */
219 void readyForNextBatch(int remainingBatchSize);
220
221 /**
222 * @internal
223 * Emitted whenever a transaction is committed. This is for testing only.
224 *
225 * @since 4.14
226 */
227 void transactionCommitted();
228
229protected:
230 void doStart();
231 void slotResult(KJob *job);
232
233 /**
234 * Reimplement this method to customize the synchronization algorithm.
235 * @param storedItem the item as it is now
236 * @param newItem the item as it should be
237 * You can update the @p newItem according to the @p storedItem before
238 * it gets committed.
239 *
240 * @deprecated This method is disabled internally.
241 */
242 AKONADI_DEPRECATED virtual bool updateItem(const Item &storedItem, Item &newItem);
243
244private:
245 //@cond PRIVATE
246 Q_DECLARE_PRIVATE(ItemSync)
247 ItemSyncPrivate *dummy; // for BC. KF5 TODO: REMOVE.
248
249 Q_PRIVATE_SLOT(d_func(), void slotLocalListDone(KJob *))
250 Q_PRIVATE_SLOT(d_func(), void slotLocalDeleteDone(KJob *))
251 Q_PRIVATE_SLOT(d_func(), void slotLocalChangeDone(KJob *))
252 Q_PRIVATE_SLOT(d_func(), void slotTransactionResult(KJob *))
253 Q_PRIVATE_SLOT(d_func(), void slotItemsReceived(const Akonadi::Item::List &))
254 //@endcond
255};
256
257}
258
259#endif
260