发布于 2015-10-07 09:57:04 | 228 次阅读 | 评论: 0 | 来源: 网络整理
        Zend_Mail can read mail messages from several local or remote mail storages. All of them have the
        same basic API 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.
    
表 25.1. Mail Read Feature Overview
| Feature | Mbox | Maildir | Pop3 | IMAP | 
|---|---|---|---|---|
| Storage type | local | local | remote | remote | 
| Fetch message | Yes | Yes | Yes | Yes | 
| Fetch mime-part | emulated | emulated | emulated | emulated | 
| Folders | Yes | Yes | No | Yes | 
| Create message/folder | No | todo | No | todo | 
| Flags | No | Yes | No | Yes | 
| Quota | No | Yes | No | No | 
$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";
}
        
Mbox and Maildir are the two supported formats for local mail storages, both in their most simple formats.
            If you want to read from a Mbox file you only need to give the filename to the constructor of
            Zend_Mail_Storage_Mbox:
        
$mail = new Zend_Mail_Storage_Mbox(array('filename' => 
                                             '/home/test/mail/inbox'));
        
Maildir is very similar but needs a dirname:
$mail = new Zend_Mail_Storage_Maildir(array('dirname' =>
                                                '/home/test/mail/'));
        
Both constructors throw a Zend_Mail_Exception if the storage can't be read.
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 RFC.
// 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'));
        
For both storages SSL and TLS are supported. If you use SSL the default port changes as given in the RFC.
// 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'));
        
            Both constructors can throw Zend_Mail_Exception or Zend_Mail_Protocol_Exception
            (extends Zend_Mail_Exception), depending on the type of error.
        
            Once you've opened the storage messages can be fetched. You need the message number, which is a counter
            starting with 1 for the first message. To fetch the message you use the method getMessage():
        
$message = $mail->getMessage($messageNum);
        
            Array access is also supported, but won't supported any additional parameters that could be added to
            getMessage(). As long as you don't mind and can live with defaults you may use:
        
$message = $mail[$messageNum];
        
For iterating over all messages the Iterator interface is implemented:
foreach ($mail as $messageNum => $message) {
    // do stuff ...
}
        
            To count the messages in the storage you can either use the method countMessages() or use array
            access:
        
// method
$maxMessage = $mail->countMessages();
// array access
$maxMessage = count($mail);
        
To remove a mail you use the method removeMessage() or again array access:
// method
$mail->removeMessage($messageNum);
// array access
unset($mail[$messageNum]);
        
After you fetched the messages with getMessage() you want to fetch headers, the content
        or single parts of a multipart message. All headers can be accessed via properties or the method
        getHeader() 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.
// get the message object
$message = $mail->getMessage(1);
// output subject of message
echo $message->subject . "\n";
// get content-type header
$type = $message->contentType;
        
If you have multiple headers with the same name i.e. the Received headers you might want it as array
        instead of a string, which is possible with the getHeader() method.
// 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
}
        
The method getHeaders() returns all headers as array with the lower-cased name as
        key and the value as array for multiple headers or as string for single headers.
// 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";
    }
}
        
If you don't have a multipart message fetching the content is easy done via
        getContent(). Unlike the headers the content is only fetched when needed (aka late-fetch).
// output message content for HTML
echo '<pre>';
echo $message->getContent();
echo '</pre>';
        
Checking for a multipart message is done with the method isMultipart(). If you have
        multipart message you can get an instance of Zend_Mail_Part with the method
        getPart(). Zend_Mail_Part is the base class of Zend_Mail_Message,
        so you have the same methods: getHeader(), getHeaders(), getContent(),
        getPart(), isMultipart and the properties for headers.
// 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();
        
Zend_Mail_Part also implements RecursiveIterator, which makes it easy to scan through all parts. And
        for easy output it also implements the magic method __toString(), which returns the content.
// 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;
}
        
Maildir and IMAP support storing flags. The class Zend_Mail_Storage has constants for all known
        maildir and IMAP system flags, named Zend_Mail_Storage::FLAG_<flagname>. To check
        for flags Zend_Mail_Message has a method called hasFlag(). With
        getFlags() you'll get all set flags.
// 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) ';
    }
}
        
As IMAP allows user or client defined flags you could get flags, that don't have a constant in
        Zend_Mail_Storage. Instead they are returned as string and can be checked the same way with
        hasFlag().
// 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';
}
        
            All storages, except Pop3, support folders, also called mailboxes. The interface implemented by all storages
            supporting folders is called Zend_Mail_Storage_Folder_Interface. Also all of these classes have an
            additional optional parameter called folder, which is the folder selected after login, in the constructor.
        
            For the local storages you need to use separate classes called Zend_Mail_Storage_Folder_Mbox or
            Zend_Mail_Storage_Folder_Maildir. Both need one parameter called dirname 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
            an other folder in the constructor.
        
            Zend_Mail_Storage_Imap already supports folders by default. Examples for opening these storages:
        
// 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'));
        
            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 instance of Zend_Mail_Storage_Folder, which implements
            RecursiveIterator and all children are also instances of Zend_Mail_Storage_Folder. Each of
            these instances has a local and a global name returned by the methods getLocalName() and
            getGlobalName(). The global name is the absolute name from the root folder (including
            delimiters), the local name is the name in the parent folder.
        
表 25.2. Mail Folder Names
| Global Name | Local Name | 
|---|---|
| /INBOX | INBOX | 
| /Archive/2005 | 2005 | 
| List.ZF.General | General | 
            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 __toString(). 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
            isSelectable(). So it's very easy to output the whole tree in a view:
        
$folders = new RecursiveIteratorIterator($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>';
        
            The current selected folders is returned by the method getSelectedFolder(). Changing the folder
            is done with the method selectFolder(), which needs the global name as parameter. If you want
            to avoid to write delimiters you can also use the properties of a Zend_Mail_Storage_Folder instance:
        
// 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->getSelectedFolder() . "new folder is $folder\n";
$mail->selectFolder($folder);
        
If you're using a remote storage and have some long tasks you might need to keep the connection alive via noop:
foreach ($mail as $message) {
    // do some calculations ...
    $mail->noop(); // keep alive
    // do something else ...
    $mail->noop(); // keep alive
}
            
            Zend_Mail_Storage_Mbox, Zend_Mail_Storage_Folder_Mbox, Zend_Mail_Storage_Maildir and
            Zend_Mail_Storage_Folder_Maildir implement the magic methods __sleep() and
            __wakeup(), 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
            are 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 an other folder
            afterwards). It's better if you have something like a signal file for changes and check it before using the
            cached instance.
            
// 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);
            
                Remote storages use two classes: Zend_Mail_Storage_<Name> and
                Zend_Mail_Protocol_<Name>. The protocol class translates the protocol commands and
                responses from and to PHP, like methods for the commands or variables with different structures for
                data. The other/main class implements the common interface.
            
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.
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)));
            
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.
            Zend_Mail_Storage_Writable_Maildir 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 
            appendMessage(), removeMessage() and copyMessage() do no checks
            and do not add entry to the maildirsize file). If enabled an exception is thrown if you try to write
            to the maildir if it's already over quota.
            
            There are three methods used for quotas: getQuota(), setQuota() and 
            checkQuota():
            
$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";
            
            checkQuota() can also return a more detailed response:
            
$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';
            
            If you want to specify your own quota instead of using the one specified in the maildirsize file you
            can do with setQuota():
            
// message count and octet size supported, order does matter
$quota = $mail->setQuota(array('size' => 10000, 'count' => 100));
            
            To add your own quota checks use single letters as key and they are preserved (but obviously not checked).
            It's also possible to extend  Zend_Mail_Storage_Writable_Maildir to define your own quota only
            if the maildirsize file is missing (which can happen in Maildir++):
            
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);
		}
	}
}