| Mail::Box::Thread::Manager(3pm) | User Contributed Perl Documentation | Mail::Box::Thread::Manager(3pm) |
Mail::Box::Thread::Manager - maintain threads within a set of folders
Mail::Box::Thread::Manager is a Mail::Reporter
my $mgr = Mail::Box::Manager->new;
my $folder = $mgr->open(folder => '/tmp/inbox');
my $threads = $mgr->threads();
$threads->includeFolder($folder);
my $threads = $msg->threads(folder => $folder);
foreach my $thread ($threads->all) {
$thread->print;
}
$threads->removeFolder($folder);
A (message-)thread is a message with links to messages which followed in reply of that message. And then the messages with replied to the messages, which replied the original message. And so on. Some threads are only one message long (never replied to), some threads are very long.
The "Mail::Box::Thread::Manager" is very powerful. Not only is it able to do a descent job on MH-like folders (makes a trade-off between perfection and speed), it also can maintain threads from messages residing in different opened folders. Both facilities are rare for mail-agents. The manager creates flexible trees with Mail::Box::Thread::Node objects.
Extends "DESCRIPTION" in Mail::Reporter.
Extends "METHODS" in Mail::Reporter.
Extends "Constructors" in Mail::Reporter.
-Option --Defined in --Default
dummy_type Mail::Message::Dummy
folder [ ]
folders [ ]
log Mail::Reporter 'WARNINGS'
thread_body <false>
thread_type Mail::Box::Thread::Node
timespan '3 days'
trace Mail::Reporter 'WARNINGS'
window 10
See Mail::Box::timespan2seconds() for the possibilities for TIME. With 'EVER', the search for messages in a thread will only be limited by the window-size.
The constant 'ALL' will cause thread-detection not to stop trying to fill holes, but continue looking until the first message of the folder is reached. Gives the best quality results, but may perform bad.
example:
use Mail::Box::Manager;
my $mgr = Mail::Box::Manager->new;
my $inbox = $mgr->open(folder => $ENV{MAIL});
my $read = $mgr->open(folder => 'Mail/read');
my $threads = $mgr->threads(folders => [$inbox, $read]);
# longer alternative for last line:
my $threads = $mgr->threads;
$threads->includeFolder($inbox);
$threads->includeFolder($read);
From the folders, the messages which have their header lines parsed (see Mail::Box about lazy extracting) will be immediately scanned. Messages of which the header is known only later will have to report this (see toBeThreaded()).
example:
$threads->includeFolder($inbox, $draft);
example:
$threads->removeFolder($draft);
To be able to return all threads, thread construction on each message is performed first, which may be slow for some folder-types because is will enforce parsing of message-bodies.
The list may contain dummy messages, and messages which are scheduled for deletion. Threads are detected based on explicitly calling inThread() and thread() with a messages from the folder.
Be warned that, each time a message's header is read from the folder, the return of the method can change.
Usually, all messages which are in reply of this message are dated later than the specified one. All headers of messages later than this one are getting parsed first, for each folder in this threads-object.
example:
my $threads = $mgr->threads(folder => $inbox); my $thread = $threads->thread($inbox->message(3)); print $thread->string;
Extends "Error handling" in Mail::Reporter.
Extends "Cleanup" in Mail::Reporter.
This module implements thread-detection on a folder. Messages created by the better mailers will include "In-Reply-To" and "References" lines, which are used to figure out how messages are related. If you prefer a better thread detection, they are implementable, but there may be a serious performance hit (depends on the type of folder used).
A "Mail::Box::Thread::Manager" object is created by the Mail::Box::Manager, using Mail::Box::Manager::threads(). Each object can monitor the thread-relations between messages in one or more folders. When more than one folder is specified, the messages are merged while reading the threads, although nothing changes in the folder-structure. Adding and removing folders which have to be maintained is permitted at any moment, although may be quite costly in performance.
An example of the maintained structure is shown below. The Mail::Box::Manager has two open folders, and a thread-builder which monitors them both. The combined folders have two threads, the second is two long (msg3 is a reply on msg2). Msg2 is in two folders at once.
manager
| \
| `----------- threads
| | |
| thread thread---thread
| | /| /
| | // /
+---- folder1 | // /
| | / // /
| `-----msg1 // /
| `-----msg2-'/ /
| / /
`-----folder2 / /
| / /
`-----msg2 /
`-----msg3------'
With all() you get the start-messages of each thread of this folder. When that message was not found in the folder (not saved or already removed), you get a message of the dummy-type. These thread descriptions are in perfect state: all messages of the folder are included somewhere, and each missing message of the threads (holes) are filled by dummies.
However, to be able to detect all threads it is required to have the headers of all messages, which is very slow for some types of folders, especially MH and IMAP folders.
For interactive mail-readers, it is preferred to detect threads only on messages which are in the viewport of the user. This may be sloppy in some situations, but everything is preferable over reading an MH mailbox with 10k e-mails to read only the see most recent messages.
In this object, we take special care not to cause unnecessary parsing (loading) of messages. Threads will only be detected on command, and by default only the message headers are used.
The following reports the Mail::Box::Thread::Node which is related to a message:
my $thread = $message->thread;
When the message was not put in a thread yet, it is done now. But, more work is done to return the best thread. Based on various parameters, which where specified when the folder was created, the method walks through the folder to fill the holes which are in this thread.
Walking from back to front (recently arrived messages are usually in the back of the folder), message after message are triggered to be included in their thread. At a certain moment, the whole thread of the requested method is found, a certain maximum number of messages was tried, but that didn't help (search window bound reached), or the messages within the folder are getting too old. Then the search to complete the thread will end, although more messages of them might have been in the folder: we don't scan the whole folder for performance reasons.
Finally, for each message where the head is known, for instance for all messages in mbox-folders, the correct thread is determined immediately. Also, all messages where the head get loaded later, are automatically included.
This module is part of Mail-Box distribution version 3.009, built on August 18, 2020. Website: http://perl.overmeer.net/CPAN/
Copyrights 2001-2020 by [Mark Overmeer]. For other contributors see ChangeLog.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://dev.perl.org/licenses/
| 2020-08-20 | perl v5.30.3 |