phpman > perldoc > Mail::Message::Construct::Build(3pm)

NAME
    Mail::Message::Construct::Build - building a Mail::Message from components

SYNOPSIS
     my $msg1 = Mail::Message->build
       ( From => 'me', data => "only two\nlines\n");

     my $msg2 = Mail::Message->buildFromBody($body);

     Mail::Message->build
       ( From     => 'me AT myhost.com'
       , To       => 'you AT yourhost.com'
       , Subject  => "Read our folder!"

       , data     => \@lines
       , file     => 'folder.pdf'
       )->send(via => 'postfix');

DESCRIPTION
    Complex functionality on Mail::Message objects is implemented in different files which are
    autoloaded. This file implements the building of messages from various simpler components.

METHODS
  Constructing a message
    Mail::Message->build( [$message|$part|$body], $content )
        Simplified message object builder. In case a $message or message $part is specified, a new
        message is created with the same body to start with, but new headers. A $body may be
        specified as well. However, there are more ways to add data simply.

        The $content is a list of key-value pairs and header field objects. The keys which start
        with a capital are used as header-lines. Lower-cased fields are used for other purposes as
        listed below. Each field may be used more than once. Pairs where the value is "undef" are
        ignored.

        If more than one "data", "file", and "attach" is specified, a multi-parted message is
        created. Some "Content-*" fields are treated separately: to enforce the content lines of the
        produced message body after it has been created. For instance, to explicitly state that you
        wish a "multipart/alternative" in stead of the default "multipart/mixed". If you wish to
        specify the type per datum, you need to start playing with Mail::Message::Body objects
        yourself.

        This "build" method will use buildFromBody() when the body object has been constructed.
        Together, they produce your message.

         -Option--Default
          attach  undef
          data    undef
          file    undef
          files   [ ]
          head    undef

        attach => BODY|PART|MESSAGE|ARRAY
          One attachment to the message. Each attachment can be full $message, a $part, or a $body.
          Any $message will get encapsulated into a "message/rfc822" body. You can specify many
          items (may be of different types) at once.

           attach => $folder->message(3)->decoded  # body
           attach => $folder->message(3)           # message
           attach => [ $msg1, $msg2->part(6), $msg3->body ];

        data => STRING|ARRAY-OF-LINES
          The text for one part, specified as one STRING, or an ARRAY of lines. Each line, including
          the last, must be terminated by a newline. This argument is passed to
          Mail::Message::Body::new(data) to construct one.

            data => [ "line 1\n", "line 2\n" ]     # array of lines
            data => <<'TEXT'                       # string
           line 1
           line 2
           TEXT

        file => FILENAME|FILEHANDLE|IOHANDLE|ARRAY
          Create a body where the data is read from the specified FILENAME, FILEHANDLE, or object of
          type IO::Handle. Also this body is used to create a Mail::Message::Body. [2.119] You may
          even pass more than one file at once: 'file' and 'files' option are equivalent.

           my $in = IO::File->new('/etc/passwd', 'r');

           file  => 'picture.jpg'                   # filename
           file  => \*MYINPUTFILE                   # file handle
           file  => $in                             # any IO::Handle
           files => [ 'picture.jpg', \*MYINPUTFILE, $in ]

           open my $in, '<:raw', '/etc/passwd';    # alternative for IO::File

        files => ARRAY-OF-FILE
          Alias for option "file".

        head => HEAD
          Start with a prepared header, otherwise one is created.

        example:

         my $msg = Mail::Message->build
          ( From    => 'me AT home.nl'
          , To      => Mail::Address->new('your name', 'you AT yourplace.aq')
          , Cc      => 'everyone AT example.com'
          , Subject => "Let's talk",
          , $other_message->get('Bcc')

          , data   => [ "This is\n", "the first part of\n", "the message\n" ]
          , file   => 'myself.gif'
          , file   => 'you.jpg'
          , attach => $signature
          );

         my $msg = Mail::Message->build
          ( To     => 'you'
          , 'Content-Type' => 'text/html'
          , data   => "<html></html>"
          );

    Mail::Message->buildFromBody($body, [$head], $headers)
        Shape a message around a $body. Bodies have information about their content in them, which
        is used to construct a header for the message. You may specify a $head object which is
        pre-initialized, or one is created for you (also when $head is "undef"). Next to that, more
        $headers can be specified which are stored in that header.

        Header fields are added in order, and before the header lines as defined by the body are
        taken. They may be supplied as key-value pairs or Mail::Message::Field objects. In case of a
        key-value pair, the field's name is to be used as key and the value is a string, address
        (Mail::Address object), or array of addresses.

        A "Date", "Message-Id", and "MIME-Version" field are added unless supplied.

        example:

         my $type = Mail::Message::Field->new('Content-Type', 'text/html'
           , 'charset="us-ascii"');

         my @to   = ( Mail::Address->new('Your name', 'you AT example.com')
                    , 'world AT example.info'
                    );

         my $msg  = Mail::Message->buildFromBody
           ( $body
           , From => 'me AT example.nl'
           , To   => \@to
           , $type
           );

DETAILS
  Building a message
   Rapid building
    Most messages you need to construct are relatively simple. Therefore, this module provides a
    method to prepare a message with only one method call: build().

   Compared to MIME::Entity::build()
    The "build" method in MailBox is modelled after the "build" method as provided by MIMETools, but
    with a few simplifications:

    When a keys starts with a capital, than it is always a header field
    When a keys is lower-cased, it is always something else
    You use the real field-names, not abbreviations
    All field names are accepted
    You may specify field objects between key-value pairs
    A lot of facts are auto-detected, like content-type and encoding
    You can create a multipart at once

    Hum, reading the list above... what is equivalent? MIME::Entity is not that simple after all!
    Let's look at an example from MIME::Entity's manual page:

     ### Create the top-level, and set up the mail headers:
     $top = MIME::Entity->build(Type     => "multipart/mixed",
                                From     => 'me AT myhost.com',
                                To       => 'you AT yourhost.com',
                                Subject  => "Hello, nurse!");

     ### Attachment #1: a simple text document:
     $top->attach(Path=>"./testin/short.txt");

     ### Attachment #2: a GIF file:
     $top->attach(Path        => "./docs/mime-sm.gif",
                  Type        => "image/gif",
                  Encoding    => "base64");

     ### Attachment #3: text we'll create with text we have on-hand:
     $top->attach(Data => $contents);

    The MailBox equivalent could be

     my $msg = Mail::Message->build
       ( From     => 'me AT myhost.com'
       , To       => 'you AT yourhost.com'
       , Subject  => "Hello, nurse!"

       , file     => "./testin/short.txt"
       , file     => "./docs/mime-sm.gif"
       , data     => $contents
       );

    One of the simplifications is that MIME::Types is used to lookup the right content type and
    optimal transfer encoding. Good values for content-disposition and such are added as well.

   build, starting with nothing
    See build().

   buildFromBody, body becomes message
    See buildFromBody().

   The Content-* fields
    The various "Content-*" fields are not as harmless as they look. For instance, the
    "Content-Type" field will have an effect on the default transfer encoding.

    When a message is built this way:

     my $msg = Mail::Message->build
      ( 'Content-Type' => 'video/mpeg3'
      , 'Content-Transfer-Encoding' => 'base64'
      , 'Content-Disposition' => 'attachment'
      , file => '/etc/passwd'
      );

    then first a "text/plain" body is constructed (MIME::Types does not find an extension on the
    filename so defaults to "text/plain"), with no encoding. Only when that body is ready, the new
    type and requested encodings are set. The content of the body will get base64 encoded, because
    it is requested that way.

    What basically happens is this:

     my $head = ...other header lines...;
     my $body = Mail::Message::Body::Lines->new(file => '/etc/passwd');
     $body->type('video/mpeg3');
     $body->transferEncoding('base64');
     $body->diposition('attachment');
     my $msg  = Mail::Message->buildFromBody($body, $head);

    A safer way to construct the message is:

     my $body = Mail::Message::Body::Lines->new
      ( file              => '/etc/passwd'
      , mime_type         => 'video/mpeg3'
      , transfer_encoding => 'base64'
      , disposition       => 'attachment'
      );

     my $msg  = Mail::Message->buildFromBody
      ( $body
      , ...other header lines...
      );

    In the latter program, you will immediately start with a body of the right type.

DIAGNOSTICS
    Error: Only build() Mail::Message's; they are not in a folder yet
        You may wish to construct a message to be stored in a some kind of folder, but you need to
        do that in two steps. First, create a normal Mail::Message, and then add it to the folder.
        During this Mail::Box::addMessage() process, the message will get coerce()-d into the right
        message type, adding storage information and the like.

SEE ALSO
    This module is part of Mail-Message distribution version 3.012, built on February 11, 2022.
    Website: http://perl.overmeer.net/CPAN/

LICENSE
    Copyrights 2001-2022 by [Mark Overmeer <markov AT cpan.org>]. 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/