File: Zend_Mail_Read.xml

package info (click to toggle)
zendframework 1.12.9%2Bdfsg-2
  • links: PTS, VCS
  • area: main
  • in suites: jessie-kfreebsd
  • size: 133,584 kB
  • sloc: xml: 1,311,829; php: 570,173; sh: 170; makefile: 125; sql: 121
file content (839 lines) | stat: -rw-r--r-- 31,500 bytes parent folder | download | duplicates (2)
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
64
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
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
<?xml version="1.0" encoding="UTF-8"?>
<!-- Reviewed: no -->
<sect1 id="zend.mail.read">
    <title>Reading Mail Messages</title>

    <para>
        <classname>Zend_Mail</classname> can read mail messages from several local or remote mail
        storages. All of them have the same basic <acronym>API</acronym> to count and fetch messages
        and some of them implement additional interfaces for not so common features. For a feature
        overview of the implemented storages, see the following table.
    </para>

    <table id="zend.mail.read.table-1">
        <title>Mail Read Feature Overview</title>

        <tgroup cols="5">
            <thead>
                <row>
                    <entry>Feature</entry>
                    <entry>Mbox</entry>
                    <entry>Maildir</entry>
                    <entry>Pop3</entry>
                    <entry><constant>IMAP</constant></entry>
                </row>
            </thead>

            <tbody>
                <row>
                    <entry>Storage type</entry>
                    <entry>local</entry>
                    <entry>local</entry>
                    <entry>remote</entry>
                    <entry>remote</entry>
                </row>

                <row>
                    <entry>Fetch message</entry>
                    <entry>Yes</entry>
                    <entry>Yes</entry>
                    <entry>Yes</entry>
                    <entry>Yes</entry>
                </row>

                <row>
                    <entry>Fetch <acronym>MIME</acronym>-part</entry>
                    <entry>emulated</entry>
                    <entry>emulated</entry>
                    <entry>emulated</entry>
                    <entry>emulated</entry>
                </row>

                <row>
                    <entry>Folders</entry>
                    <entry>Yes </entry>
                    <entry>Yes</entry>
                    <entry>No</entry>
                    <entry>Yes</entry>
                </row>

                <row>
                    <entry>Create message/folder</entry>
                    <entry>No</entry>
                    <entry>todo</entry>
                    <entry>No</entry>
                    <entry>todo</entry>
                </row>

                <row>
                    <entry>Flags</entry>
                    <entry>No</entry>
                    <entry>Yes</entry>
                    <entry>No</entry>
                    <entry>Yes</entry>
                </row>

                <row>
                    <entry>Quota</entry>
                    <entry>No</entry>
                    <entry>Yes</entry>
                    <entry>No</entry>
                    <entry>No</entry>
                </row>
            </tbody>
        </tgroup>
    </table>

    <sect2 id="zend.mail.read-example">
        <title>Simple example using Pop3</title>

        <programlisting language="php"><![CDATA[
$mail = new Zend_Mail_Storage_Pop3(array('host'     => 'localhost',
                                         'user'     => 'test',
                                         'password' => 'test'));

echo $mail->countMessages() . " messages found\n";
foreach ($mail as $message) {
    echo "Mail from '{$message->from}': {$message->subject}\n";
}
]]></programlisting>
    </sect2>

    <sect2 id="zend.mail.read-open-local">
        <title>Opening a local storage</title>

        <para>
            Mbox and Maildir are the two supported formats for local mail storages, both in their
            most simple formats.
        </para>

        <para>
            If you want to read from a Mbox file you only need to give the filename to the
            constructor of <classname>Zend_Mail_Storage_Mbox</classname>:
        </para>

        <programlisting language="php"><![CDATA[
$mail = new Zend_Mail_Storage_Mbox(array('filename' =>
                                             '/home/test/mail/inbox'));
]]></programlisting>

        <para>Maildir is very similar but needs a dirname:</para>

        <programlisting language="php"><![CDATA[
$mail = new Zend_Mail_Storage_Maildir(array('dirname' =>
                                                '/home/test/mail/'));
]]></programlisting>

        <para>
            Both constructors throw a <classname>Zend_Mail_Exception</classname> if the storage
            can't be read.
        </para>
    </sect2>

    <sect2 id="zend.mail.read-open-remote">
        <title>Opening a remote storage</title>

        <para>
            For remote storages the two most popular protocols are supported: Pop3 and Imap. Both
            need at least a host and a user to connect and login. The default password is an empty
            string, the default port as given in the protocol <acronym>RFC</acronym>.
        </para>

        <programlisting language="php"><![CDATA[
// connecting with Pop3
$mail = new Zend_Mail_Storage_Pop3(array('host'     => 'example.com',
                                         'user'     => 'test',
                                         'password' => 'test'));

// connecting with Imap
$mail = new Zend_Mail_Storage_Imap(array('host'     => 'example.com',
                                         'user'     => 'test',
                                         'password' => 'test'));

// example for a none standard port
$mail = new Zend_Mail_Storage_Pop3(array('host'     => 'example.com',
                                         'port'     => 1120
                                         'user'     => 'test',
                                         'password' => 'test'));
]]></programlisting>

        <para>
            For both storages <acronym>SSL</acronym> and TLS are supported. If you use
            <acronym>SSL</acronym> the default port changes as given in the <acronym>RFC</acronym>.
        </para>

        <programlisting language="php"><![CDATA[
// examples for Zend_Mail_Storage_Pop3, same works for Zend_Mail_Storage_Imap

// use SSL on different port (default is 995 for Pop3 and 993 for Imap)
$mail = new Zend_Mail_Storage_Pop3(array('host'     => 'example.com',
                                         'user'     => 'test',
                                         'password' => 'test',
                                         'ssl'      => 'SSL'));

// use TLS
$mail = new Zend_Mail_Storage_Pop3(array('host'     => 'example.com',
                                         'user'     => 'test',
                                         'password' => 'test',
                                         'ssl'      => 'TLS'));
]]></programlisting>

        <para>
            Both constructors can throw <classname>Zend_Mail_Exception</classname> or
            <classname>Zend_Mail_Protocol_Exception</classname> (extends
            <classname>Zend_Mail_Exception</classname>), depending on the type of error.
        </para>
    </sect2>

    <sect2 id="zend.mail.read-fetching">
        <title>Fetching messages and simple methods</title>

        <para>
            Messages can be fetched after you've opened the storage . You need the message number,
            which is a counter starting with 1 for the first message. To fetch the message, you use
            the method <methodname>getMessage()</methodname>:
        </para>

        <programlisting language="php"><![CDATA[
$message = $mail->getMessage($messageNum);
]]></programlisting>

        <para>
            Array access is also supported, but this access method won't supported any additional
            parameters that could be added to <methodname>getMessage()</methodname>. As long as you
            don't mind, and can live with the default values, you may use:
        </para>

        <programlisting language="php"><![CDATA[
$message = $mail[$messageNum];
]]></programlisting>

        <para>For iterating over all messages the Iterator interface is implemented:</para>

        <programlisting language="php"><![CDATA[
foreach ($mail as $messageNum => $message) {
    // do stuff ...
}
]]></programlisting>

        <para>
            To count the messages in the storage, you can either use the method
            <methodname>countMessages()</methodname> or use array access:
        </para>

        <programlisting language="php"><![CDATA[
// method
$maxMessage = $mail->countMessages();

// array access
$maxMessage = count($mail);
]]></programlisting>

        <para>
            To remove a mail, you use the method <methodname>removeMessage()</methodname> or again
            array access:
        </para>

        <programlisting language="php"><![CDATA[
// method
$mail->removeMessage($messageNum);

// array access
unset($mail[$messageNum]);
]]></programlisting>
    </sect2>

    <sect2 id="zend.mail.read-message">
        <title>Working with messages</title>

        <para>
            After you fetch the messages with <methodname>getMessage()</methodname> you want to
            fetch headers, the content or single parts of a multipart message. All headers can be
            accessed via properties or the method <methodname>getHeader()</methodname> if you want
            more control or have unusual header names. The header names are lower-cased internally,
            thus the case of the header name in the mail message doesn't matter. Also headers with a
            dash can be written in camel-case. If no header is found for both notations an exception
            is thrown. To encounter this the method <methodname>headerExists()</methodname> can be
            used to check the existence of a header.
        </para>

        <programlisting language="php"><![CDATA[
// get the message object
$message = $mail->getMessage(1);

// output subject of message
echo $message->subject . "\n";

// get content-type header
$type = $message->contentType;

// check if CC isset:
if( isset($message->cc) ) { // or $message->headerExists('cc');
    $cc = $message->cc;
}
]]></programlisting>

        <para>
            If you have multiple headers with the same name- i.e. the Received headers- you might
            want an array instead of a string. In this case, use the
            <methodname>getHeader()</methodname> method.
        </para>

        <programlisting language="php"><![CDATA[
// get header as property - the result is always a string,
// with new lines between the single occurrences in the message
$received = $message->received;

// the same via getHeader() method
$received = $message->getHeader('received', 'string');

// better an array with a single entry for every occurrences
$received = $message->getHeader('received', 'array');
foreach ($received as $line) {
    // do stuff
}

// if you don't define a format you'll get the internal representation
// (string for single headers, array for multiple)
$received = $message->getHeader('received');
if (is_string($received)) {
    // only one received header found in message
}
]]></programlisting>

        <para>
            The method <methodname>getHeaders()</methodname> returns all headers as array with the
            lower-cased name as key and the value as and array for multiple headers or as string for
            single headers.
        </para>

        <programlisting language="php"><![CDATA[
// dump all headers
foreach ($message->getHeaders() as $name => $value) {
    if (is_string($value)) {
        echo "$name: $value\n";
        continue;
    }
    foreach ($value as $entry) {
        echo "$name: $entry\n";
    }
}
]]></programlisting>

        <para>
            If you don't have a multipart message, fetching the content is easily done via
            <methodname>getContent()</methodname>. Unlike the headers, the content is only fetched
            when needed (aka late-fetch).
        </para>

        <programlisting language="php"><![CDATA[
// output message content for HTML
echo '<pre>';
echo $message->getContent();
echo '</pre>';
]]></programlisting>

        <para>
            Checking for multipart messages is done with the method
            <methodname>isMultipart()</methodname>. If you have multipart message you can get an
            instance of <classname>Zend_Mail_Part</classname> with the method
            <methodname>getPart()</methodname>. <classname>Zend_Mail_Part</classname> is the base
            class of <classname>Zend_Mail_Message</classname>, so you have the same methods:
            <methodname>getHeader()</methodname>, <methodname>getHeaders()</methodname>,
            <methodname>getContent()</methodname>, <methodname>getPart()</methodname>,
            <methodname>isMultipart()</methodname> and the properties for headers.
        </para>

        <programlisting language="php"><![CDATA[
// get the first none multipart part
$part = $message;
while ($part->isMultipart()) {
    $part = $message->getPart(1);
}
echo 'Type of this part is ' . strtok($part->contentType, ';') . "\n";
echo "Content:\n";
echo $part->getContent();
]]></programlisting>

        <para>
            <classname>Zend_Mail_Part</classname> also implements
            <classname>RecursiveIterator</classname>, which makes it easy to scan through all
            parts. And for easy output, it also implements the magic method
            <methodname>__toString()</methodname>, which returns the content.
        </para>

        <programlisting language="php"><![CDATA[
// output first text/plain part
$foundPart = null;
foreach (new RecursiveIteratorIterator($mail->getMessage(1)) as $part) {
    try {
        if (strtok($part->contentType, ';') == 'text/plain') {
            $foundPart = $part;
            break;
        }
    } catch (Zend_Mail_Exception $e) {
        // ignore
    }
}
if (!$foundPart) {
    echo 'no plain text part found';
} else {
    echo "plain text part: \n" . $foundPart;
}
]]></programlisting>
    </sect2>

    <sect2 id="zend.mail.read-flags">
        <title>Checking for flags</title>

        <para>
            Maildir and IMAP support storing flags. The class
            <classname>Zend_Mail_Storage</classname> has constants for all known maildir and IMAP
            system flags, named <classname>Zend_Mail_Storage::FLAG_&lt;flagname&gt;</classname>. To
            check for flags <classname>Zend_Mail_Message</classname> has a method called
            <methodname>hasFlag()</methodname>. With <methodname>getFlags()</methodname> you'll get
            all set flags.
        </para>

        <programlisting language="php"><![CDATA[
// find unread messages
echo "Unread mails:\n";
foreach ($mail as $message) {
    if ($message->hasFlag(Zend_Mail_Storage::FLAG_SEEN)) {
        continue;
    }
    // mark recent/new mails
    if ($message->hasFlag(Zend_Mail_Storage::FLAG_RECENT)) {
        echo '! ';
    } else {
        echo '  ';
    }
    echo $message->subject . "\n";
}

// check for known flags
$flags = $message->getFlags();
echo "Message is flagged as: ";
foreach ($flags as $flag) {
    switch ($flag) {
        case Zend_Mail_Storage::FLAG_ANSWERED:
            echo 'Answered ';
            break;
        case Zend_Mail_Storage::FLAG_FLAGGED:
            echo 'Flagged ';
            break;

        // ...
        // check for other flags
        // ...

        default:
            echo $flag . '(unknown flag) ';
    }
}
]]></programlisting>

        <para>
            As IMAP allows user or client defined flags, you could get flags that don't have a
            constant in <classname>Zend_Mail_Storage</classname>. Instead, they are returned as
            strings and can be checked the same way with <methodname>hasFlag()</methodname>.
        </para>

        <programlisting language="php"><![CDATA[
// check message for client defined flags $IsSpam, $SpamTested
if (!$message->hasFlag('$SpamTested')) {
    echo 'message has not been tested for spam';
} else if ($message->hasFlag('$IsSpam')) {
    echo 'this message is spam';
} else {
    echo 'this message is ham';
}
]]></programlisting>
    </sect2>

    <sect2 id="zend.mail.read-folders">
        <title>Using folders</title>

        <para>
            All storages, except Pop3, support folders, also called mailboxes. The interface
            implemented by all storages supporting folders is called
            <classname>Zend_Mail_Storage_Folder_Interface</classname>. Also all of these classes
            have an additional optional parameter called <property>folder</property>, which is the
            folder selected after login, in the constructor.
        </para>

        <para>
            For the local storages you need to use separate classes called
            <classname>Zend_Mail_Storage_Folder_Mbox</classname> or
            <classname>Zend_Mail_Storage_Folder_Maildir</classname>. Both need one parameter called
            <property>dirname</property> with the name of the base dir. The format for maildir is as
            defined in maildir++ (with a dot as default delimiter), Mbox is a directory hierarchy
            with Mbox files. If you don't have a Mbox file called INBOX in your Mbox base dir you
            need to set another folder in the constructor.
        </para>

        <para>
            <classname>Zend_Mail_Storage_Imap</classname> already supports folders by default.
            Examples for opening these storages:
        </para>

        <programlisting language="php"><![CDATA[
// mbox with folders
$mail = new Zend_Mail_Storage_Folder_Mbox(array('dirname' =>
                                                    '/home/test/mail/'));

// mbox with a default folder not called INBOX, also works
// with Zend_Mail_Storage_Folder_Maildir and Zend_Mail_Storage_Imap
$mail = new Zend_Mail_Storage_Folder_Mbox(array('dirname' =>
                                                    '/home/test/mail/',
                                                'folder'  =>
                                                    'Archive'));

// maildir with folders
$mail = new Zend_Mail_Storage_Folder_Maildir(array('dirname' =>
                                                       '/home/test/mail/'));

// maildir with colon as delimiter, as suggested in Maildir++
$mail = new Zend_Mail_Storage_Folder_Maildir(array('dirname' =>
                                                       '/home/test/mail/',
                                                   'delim'   => ':'));

// imap is the same with and without folders
$mail = new Zend_Mail_Storage_Imap(array('host'     => 'example.com',
                                         'user'     => 'test',
                                         'password' => 'test'));
]]></programlisting>

        <para>
            With the method getFolders($root = null) you can get the folder hierarchy starting with
            the root folder or the given folder. It's returned as an instance of
            <classname>Zend_Mail_Storage_Folder</classname>, which implements
            <classname>RecursiveIterator</classname> and all children are also instances of
            <classname>Zend_Mail_Storage_Folder</classname>. Each of these instances has a local and
            a global name returned by the methods <methodname>getLocalName()</methodname> and
            <methodname>getGlobalName()</methodname>. The global name is the absolute name from the
            root folder (including delimiters), the local name is the name in the parent folder.
        </para>

        <table id="zend.mail.read-folders.table-1">
            <title>Mail Folder Names</title>

            <tgroup cols="2">
                <thead>
                    <row>
                        <entry>Global Name</entry>
                        <entry>Local Name</entry>
                    </row>
                </thead>

                <tbody>
                    <row>
                        <entry>/INBOX</entry>
                        <entry>INBOX</entry>
                    </row>

                    <row>
                        <entry>/Archive/2005</entry>
                        <entry>2005</entry>
                    </row>

                    <row>
                        <entry>List.ZF.General</entry>
                        <entry>General</entry>
                    </row>
                </tbody>
            </tgroup>
        </table>

        <para>
            If you use the iterator, the key of the current element is the local name. The global
            name is also returned by the magic method <methodname>__toString()</methodname>. Some
            folders may not be selectable, which means they can't store messages and selecting them
            results in an error. This can be checked with the method
            <methodname>isSelectable()</methodname>. So it's very easy to output the whole tree in a
            view:
        </para>

        <programlisting language="php"><![CDATA[
$folders = new RecursiveIteratorIterator($this->mail->getFolders(),
                                         RecursiveIteratorIterator::SELF_FIRST);
echo '<select name="folder">';
foreach ($folders as $localName => $folder) {
    $localName = str_pad('', $folders->getDepth(), '-', STR_PAD_LEFT) .
                 $localName;
    echo '<option';
    if (!$folder->isSelectable()) {
        echo ' disabled="disabled"';
    }
    echo ' value="' . htmlspecialchars($folder) . '">'
        . htmlspecialchars($localName) . '</option>';
}
echo '</select>';
]]></programlisting>

        <para>
            The current selected folder is returned by the method
            <methodname>getCurrentFolder()</methodname>. Changing the folder is done with the
            method <methodname>selectFolder()</methodname>, which needs the global name as
            parameter. If you want to avoid to write delimiters you can also use the properties of a
            <classname>Zend_Mail_Storage_Folder</classname> instance:
        </para>

        <programlisting language="php"><![CDATA[
// depending on your mail storage and its settings $rootFolder->Archive->2005
// is the same as:
//   /Archive/2005
//  Archive:2005
//  INBOX.Archive.2005
//  ...
$folder = $mail->getFolders()->Archive->2005;
echo 'Last folder was '
   . $mail->getCurrentFolder()
   . "new folder is $folder\n";
$mail->selectFolder($folder);
]]></programlisting>
    </sect2>

    <sect2 id="zend.mail.read-advanced">
        <title>Advanced Use</title>

        <sect3 id="zend.mail.read-advanced.noop">
            <title>Using NOOP</title>

            <para>
                If you're using a remote storage and have some long tasks you might need to keep
                the connection alive via noop:
            </para>

            <programlisting language="php"><![CDATA[
foreach ($mail as $message) {

    // do some calculations ...

    $mail->noop(); // keep alive

    // do something else ...

    $mail->noop(); // keep alive
}
]]></programlisting>
        </sect3>

        <sect3 id="zend.mail.read-advanced.caching">
            <title>Caching instances</title>

            <para>
                <classname>Zend_Mail_Storage_Mbox</classname>,
                <classname>Zend_Mail_Storage_Folder_Mbox</classname>,
                <classname>Zend_Mail_Storage_Maildir</classname> and
                <classname>Zend_Mail_Storage_Folder_Maildir</classname> implement the magic methods
                <methodname>__sleep()</methodname> and <methodname>__wakeup()</methodname>, which
                means they are serializable. This avoids parsing the files or directory tree more
                than once. The disadvantage is that your Mbox or Maildir storage should not change.
                Some easy checks may be done, like reparsing the current Mbox file if the
                modification time changes, or reparsing the folder structure if a folder has
                vanished (which still results in an error, but you can search for another folder
                afterwards). It's better if you have something like a signal file for changes and
                check it before using the cached instance.
            </para>

            <programlisting language="php"><![CDATA[
// there's no specific cache handler/class used here,
// change the code to match your cache handler
$signal_file = '/home/test/.mail.last_change';
$mbox_basedir = '/home/test/mail/';
$cache_id = 'example mail cache ' . $mbox_basedir . $signal_file;

$cache = new Your_Cache_Class();
if (!$cache->isCached($cache_id) ||
    filemtime($signal_file) > $cache->getMTime($cache_id)) {
    $mail = new Zend_Mail_Storage_Folder_Pop3(array('dirname' =>
                                                        $mbox_basedir));
} else {
    $mail = $cache->get($cache_id);
}

// do stuff ...

$cache->set($cache_id, $mail);
]]></programlisting>
        </sect3>

        <sect3 id="zend.mail.read-advanced.extending">
            <title>Extending Protocol Classes</title>

            <para>
                Remote storages use two classes:
                <classname>Zend_Mail_Storage_&lt;Name&gt;</classname> and
                <classname>Zend_Mail_Protocol_&lt;Name&gt;</classname>. The protocol class
                translates the protocol commands and responses from and to <acronym>PHP</acronym>,
                like methods for the commands or variables with different structures for data.
                The other/main class implements the common interface.
            </para>

            <para>
                If you need additional protocol features, you can extend the protocol class and use
                it in the constructor of the main class. As an example, assume we need to knock
                different ports before we can connect to POP3.
            </para>

            <programlisting language="php"><![CDATA[
class Example_Mail_Exception extends Zend_Mail_Exception
{
}

class Example_Mail_Protocol_Exception extends Zend_Mail_Protocol_Exception
{
}

class Example_Mail_Protocol_Pop3_Knock extends Zend_Mail_Protocol_Pop3
{
    private $host, $port;

    public function __construct($host, $port = null)
    {
        // no auto connect in this class
        $this->host = $host;
        $this->port = $port;
    }

    public function knock($port)
    {
        $sock = @fsockopen($this->host, $port);
        if ($sock) {
            fclose($sock);
        }
    }

    public function connect($host = null, $port = null, $ssl = false)
    {
        if ($host === null) {
            $host = $this->host;
        }
        if ($port === null) {
            $port = $this->port;
        }
        parent::connect($host, $port);
    }
}

class Example_Mail_Pop3_Knock extends Zend_Mail_Storage_Pop3
{
    public function __construct(array $params)
    {
        // ... check $params here! ...
        $protocol = new Example_Mail_Protocol_Pop3_Knock($params['host']);

        // do our "special" thing
        foreach ((array)$params['knock_ports'] as $port) {
            $protocol->knock($port);
        }

        // get to correct state
        $protocol->connect($params['host'], $params['port']);
        $protocol->login($params['user'], $params['password']);

        // initialize parent
        parent::__construct($protocol);
    }
}

$mail = new Example_Mail_Pop3_Knock(array('host'        => 'localhost',
                                          'user'        => 'test',
                                          'password'    => 'test',
                                          'knock_ports' =>
                                              array(1101, 1105, 1111)));
]]></programlisting>

            <para>
                As you see, we always assume we're connected, logged in and, if supported, a folder
                is selected in the constructor of the main class. Thus if you assign your own
                protocol class, you always need to make sure that's done or the next method will
                fail if the server doesn't allow it in the current state.
            </para>
        </sect3>

        <sect3 id="zend.mail.read-advanced.quota">
            <title>Using Quota (since 1.5)</title>

            <para>
                <classname>Zend_Mail_Storage_Writable_Maildir</classname> has support for Maildir++
                quotas. It's disabled by default, but it's possible to use it manually, if the
                automatic checks are not desired (this means
                <methodname>appendMessage()</methodname>, <methodname>removeMessage()</methodname>
                and <methodname>copyMessage()</methodname> do no checks and do not add entries to
                the maildirsize file). If enabled, an exception is thrown if you try to write to the
                maildir and it's already over quota.
            </para>

            <para>
                There are three methods used for quotas: <methodname>getQuota()</methodname>,
                <methodname>setQuota()</methodname> and <methodname>checkQuota()</methodname>:
            </para>

            <programlisting language="php"><![CDATA[
$mail = new Zend_Mail_Storage_Writable_Maildir(array('dirname' =>
                                                   '/home/test/mail/'));
$mail->setQuota(true); // true to enable, false to disable
echo 'Quota check is now ', $mail->getQuota() ? 'enabled' : 'disabled', "\n";
// check quota can be used even if quota checks are disabled
echo 'You are ', $mail->checkQuota() ? 'over quota' : 'not over quota', "\n";
]]></programlisting>

            <para>
                <methodname>checkQuota()</methodname> can also return a more detailed response:
            </para>

            <programlisting language="php"><![CDATA[
$quota = $mail->checkQuota(true);
echo 'You are ', $quota['over_quota'] ? 'over quota' : 'not over quota', "\n";
echo 'You have ',
     $quota['count'],
     ' of ',
     $quota['quota']['count'],
     ' messages and use ';
echo $quota['size'], ' of ', $quota['quota']['size'], ' octets';
]]></programlisting>

            <para>
                If you want to specify your own quota instead of using the one specified in the
                maildirsize file you can do with <methodname>setQuota()</methodname>:
            </para>

            <programlisting language="php"><![CDATA[
// message count and octet size supported, order does matter
$quota = $mail->setQuota(array('size' => 10000, 'count' => 100));
]]></programlisting>

            <para>
                To add your own quota checks use single letters as keys, and they will be preserved
                (but obviously not checked). It's also possible to extend
                <classname>Zend_Mail_Storage_Writable_Maildir</classname> to define your own quota
                only if the maildirsize file is missing (which can happen in Maildir++):
            </para>

            <programlisting language="php"><![CDATA[
class Example_Mail_Storage_Maildir extends Zend_Mail_Storage_Writable_Maildir {
    // getQuota is called with $fromStorage = true by quota checks
    public function getQuota($fromStorage = false) {
        try {
            return parent::getQuota($fromStorage);
        } catch (Zend_Mail_Storage_Exception $e) {
            if (!$fromStorage) {
                // unknown error:
                throw $e;
            }
            // maildirsize file must be missing

            list($count, $size) = get_quota_from_somewhere_else();
            return array('count' => $count, 'size' => $size);
        }
    }
}
]]></programlisting>
        </sect3>
    </sect2>
</sect1>
<!--
vim:se ts=4 sw=4 et:
-->