# Mail::Box-Cookbook - phpMan

## NAME
    [Mail::Box]-Cookbook - Examples how to use [Mail::Box]

## DESCRIPTION
    The [Mail::Box] package is a suite of classes for accessing and managing
    email folders in a folder-independent manner. This manual demonstrates a
    few simple applications. Please contribute with examples and fixes. It
    may also help to have a look at the programs included in the "scripts/"
    and the "examples/" directories of the distribution.

  The Manager
    For more details about all the packages which are involved in the
    [Mail::Box] suite you have to read [Mail::Box]-Overview. But you do not need
    to know much if you want to use the [Mail::Box] suite.

    Please use the manager to open your folders. You will certainly benefit
    from it. The manager takes care of detecting which folder type you are
    using, and which folders are open. The latter avoids the accidental
    re-opening of an already open folder.

    The "examples/open.pl" script contains mainly

     my $mgr    = [Mail::Box::Manager]->new;
     my $folder = $mgr->open($filename);
     foreach my $message ($folder->messages) {
         print $message->get('Subject') || '<no subject>', "\n";
     }
     $folder->close;

    which shows all the most important functions. It will cause all subjects
    of the messages in the indicated folder to be listed. So: although the
    number of packages included in the [Mail::Box] module is huge, only little
    is needed for normal programs.

    In stead of calling "close" on the folder, you may also call

     $mgr->closeAllFolders;

    If you forget to close a folder, changes will not be written. This may
    change in the future.

  Multi part messages
    In early days of Internet, multi-part messages were very rare. However,
    in recent years, a large deal of all transmitted message have
    attachments. This makes handling of the bodies of messages a bit harder:
    when a message contains more than one part, which part is then the most
    important to read?

    To complicate life, multi-parts can be nested: each part may be a
    multi-part by itself. This means that programs handling the message
    content must be recursive or skip multi-parts.

    The central part of the "examples/multipart.pl" script reads:

     foreach my $message ($folder->messages) {
         show_type($message);
     }

     show_type($) {
         my $msg = shift;
         print $msg->get('Content-Type'), "\n";

         if($msg->isMultipart) {
             foreach my $part ($msg->parts) {
                 show_type($part);
             }
         }
     }

    Each part is a message by itself. It has a header and a body. A
    multipart message has a special body: it contains a list of parts and
    optionally also a preamble and an epilogue, which are respectively the
    lines before and after the parts. These texts may be ignored, because
    they are only descriptive on how the multi-part was created.

  Filter
    The target is to select a few messages from one folder, to move them to
    an other. The "examples/takelarge.pl" script demonstrates how to achieve
    this. Be warned: it will replace your input folder!

    As abstract of the crucial part:

     my $inbox = $mgr->open('inbox', access => 'rw');
     my $large = $mgr->open('large', access => 'a', create => 1);

     foreach my $message ($inbox->messages) {
         next if $message->size < $size;
         $mgr->moveMessage($large, $message);
     }

     $inbox->close;
     $large->close;

    The "inbox" is opened for read and write: first read all messages, and
    then write the smaller folder without moved messages back. The "large"
    folder is created if the file does not exist yet. In any case, messages
    will be added to the end of the folder.

    The manager is needed to move the message: to unregister the message
    from the first folder, and reregister it in the second. You can move
    more messages at once, if you like. When you move to a folder which is
    not open, you even better do that: it will be faster:

     my @move = grep {$_->size >= $size} $inbox->messages;
     $mgr->moveMessage($large, @move);

    In this example, the "size" of the message determines whether the
    message is moved or not. Of course, there are many other criteria you
    can use. For instance, use "timestamp" to find old messages:

     use constant YEAR => 365 * 24 * 60 * 60;
     my $now = time;
     my @old = grep {$_->timestamp - $now > YEAR} $inbox->messages;
     $mgr->moveMessage($oldbox, @old);

  Create a reply
    The complex message treatment is implemented in [Mail::Message::Construct]
    and automatically loaded when needed. It is sufficient to simply call
    "reply" on any message:

     my $folder  = ...;
     my $message = $folder->[message(8)];
     my $reply   = $message->reply;

     $folder->addMessage($reply);
     $reply->print;

    The method is quite complex, as demonstrated by "examples/reply.pl", in
    which the construction of a reply-message is shown.

    Three kinds of reply messages can be made: one which does not include
    the original message at all (NO), then one which inlines the original
    message quoted (INLINE), and as third possibility the original message
    as attachment (ATTACH).

    The "include" parameter selects the kind of reply. When you reply to
    binary or multi-part messages, INLINE will automatically promoted to
    ATTACH. By default text will be stripped from the original senders
    signature. Multi-part messages are stripped from attachments which
    qualify as signature. In case a multi-part (after stripping) only
    contains one part, and that INLINE is requested, it will be 'flattened':
    the reply may be a single-part.

    Have a look at the parameters which can be passed to reply in
    [Mail::Message::Construct]. For a single-part reply, the return will be

     prelude
     quoted original
     postlude
     --
     signature

    A multipart body will be

     part 1: prelude
             [ see attachment ]
             postlude
     part 2: stripped original multipart
     part 3: signature

  Build a message
    There are three ways to create a message which is not a reply:

    *   [Mail::Message::buildFromBody]()

        Start with creating a body, and transform that into a message.

    *   [Mail::Message::build]()

        create the whole message at once.

    *   [Mail::Message::read]()

        read a message from a file-handle, scalar, or array of lines.

    All three methods are implemented in [Mail::Message::Construct]. Please,
    do yourself a favor, and give preference to the "build*" methods, over
    the "read", because they are much more powerful. Use the "read" only
    when you have the message on STDIN or an array of lines which is
    supplied by an external program.

    Very important to remember from now on: information about the content of
    the body (the "Content-*" lines in the header) is stored within the body
    object, for as long as the body is not contained with a message object.

    For instance, $message method "decoded" returns the decoded body of the
    $message. It is a body object by itself, however outside a real message.
    Then you may want to play around with it, by concatenating some texts:
    again resulting in a new body. Each body contains the right "Content-*"
    information. Then, finally, you create a message specifying the body and
    extra header lines. At that moment you need to specify the source and
    destination addresses (the "From" and "To" lines>). At that moment, the
    body will automatically be encoded to be acceptable for mail folders and
    transmission programs.

     my $body = [Mail::Message::Body]->new
      ( mime_type         => 'text/css'
      , transfer_encoding => '8bit'
      , data              => \@lines
      );

    Above example creates a body, with explicitly stating what kind of data
    is stored in it. The default mime type is "text/plain". The transfer
    encoding defaults to "none". Each message will get encoded on the moment
    it is added to a message. The default encoding depends on the mime type.

    To start with the first way to create a message. This solution provides
    maximum control over the message creation. Quite some work is hidden for
    you when executing the next line.

     my $message = [Mail::Message]->buildFromBody
       ( $body
       , From => '<me@example.com>'
       , To   => '<you@anywhere.net>'
       , Cc   => [ [Mail::Address]->parse($groupalias) ]
       );

    For header lines, you may specify a string, an address object
    ([Mail::Address]), or an array of such addresses. If you want to create
    multi-part messages, you need to create a multi-part body yourself
    first.

    The second way of constructing a message uses the "build" method. A
    demonstration can be found in "examples/build.pl". In only one class
    method call the header and the (possible multi-parted) body is created.

    With the "data" option, you can specify one scalar which contains a
    whole body or an array of lines. Using the "file" option, a file-handle
    or filename specifies a body. The "attach" option refers to construed
    bodies and messages. Each option can be used as often as needed. If more
    than one source of data is provided, a multi-part message is produced.

     my $message = [Mail::Message]->build
      ( From       => '<me@example.com>'
      , To         => '<you@anywhere.net>'
      , 'X-Mailer' => 'Automatic mailing system'
      , data       => \@lines
      , file       => 'logo.jpg'
      , attach     => $signature_body
      );

## SEE ALSO
    This module is part of Mail-Box distribution version 3.009, built on
    August 18, 2020. Website: <http://perl.overmeer.net/CPAN/>

## LICENSE
    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/>