Mail::Transport::IMAP4 - proxy to Mail::IMAPClient


Mail::Transport::IMAP4 - proxy to Mail::IMAPClient


   is a Mail::Transport::Receive
   is a Mail::Transport
   is a Mail::Reporter


 my $imap = Mail::Transport::IMAP4->new(...);
 my $message = $imap->receive($id);


****** UNDER DEVELOPMENT *****, please help testing

The IMAP4 protocol is quite complicated: it is feature rich and allows verious asynchronous actions. The main document describing IMAP is rfc3501 (which obsoleted the original specification of protocol 4r1 in rfc2060 in March 2003).

This package, as part of MailBox, does not implement the actual protocol itself but uses Mail::IMAPClient to do the work. The task for this package is to hide as many differences between that module's interface and the common Mail::Box folder types. Multiple Mail::Box::IMAP4 folders can share one Mail::Transport::IMAP4 connection.



Represent this imap4 connection as URL.



Create the IMAP connection to the server. IMAP servers can handle multiple folders for a single user, which means that connections may get shared. This is sharing is hidden for the user.

When an imap_client is specified, then the options hostname, port, username, and password are extracted from it.

 Option        Defined in       Default                             
 authenticate                   C<'AUTO'>                           
 domain                         <server_name>                       
 executable    L<Mail::Transport>  C<undef>                            
 hostname      L<Mail::Transport>  C<'localhost'>                      
 imap_client                    L<Mail::IMAPClient|Mail::IMAPClient>
 interval      L<Mail::Transport>  C<30>                               
 log           L<Mail::Reporter>  C<'WARNINGS'>                       
 password      L<Mail::Transport>  undef                               
 port          L<Mail::Transport>  143                                 
 proxy         L<Mail::Transport>  undef                               
 retry         L<Mail::Transport>  <false>                             
 timeout       L<Mail::Transport>  C<120>                              
 trace         L<Mail::Reporter>  C<'WARNINGS'>                       
 username      L<Mail::Transport>  undef                               
 via           L<Mail::Transport>  C<'imap'>

. authenticate TYPE|ARRAY-OF-TYPES

Authenthication method to login(), which will be passed to the Mail::IMAPClient manpage method authenticate(). See the latter method for the available types.


Used for NTLM authentication.

. executable FILENAME


. imap_client OBJECT|CLASS

When an OBJECT is supplied, that client will be used for the implementation of the IMAP4 protocol. Information about server and such are extracted from the OBJECT to have the accessors to produce correct results. The OBJECT shall be a Mail::IMAPClient.

When a CLASS is given, an object of that type is created for you. The created object can be retreived via imapClient(), and than configured as defined by Mail::IMAPClient.

. interval SECONDS

. log LEVEL

. password STRING

. port INTEGER

. proxy PATH

. retry NUMBER|undef

. timeout SECONDS

. trace LEVEL

. username STRING


Receiving mail


See Receiving mail in the Mail::Transport::Receive manpage

Server connection

$obj->findBinary(NAME [, DIRECTORIES])

See Server connection in the Mail::Transport manpage


See Server connection in the Mail::Transport manpage


See Server connection in the Mail::Transport manpage



Returned is a list of pairs (ref arrays) each describing one possible way to contact the server. Each pair contains a mechanism name and a challange callback (which may be undef).

The settings are used by login() to get server access. The initial value origins from new(authenticate), but may be changed later.

Available basic TYPES are CRAM-MD5 and PLAIN. The latter is sending username and password in plain text, and is therefore tried as last resort.

The NTLM authentication requires Authen::NTLM to be installed. Other methods may be added later. Besides, you may also specify a CODE reference which implements some authentication.

When AUTO is given, then CRAM-MD5, NTLM and PLAIN are tried, in that specific order. When the Authen::NTLM is not installed it will silently be skipped. Be warned that, because of PLAIN, erroneous username/password combinations will be passed readible as last attempt!

An ARRAY as TYPE can be used to specify both mechanism as callback. When no array is used, callback of the pair is set to undef. See authenticate in the Mail::IMAPCleint manpage for the gory details.


 $transporter->authentication('CRAM-MD5', [MY_AUTH => \&c], 'PLAIN');
 foreach my $pair ($transporter->authentication)
 {   my ($mechanism, $challange) = @$pair;


Used in NTLM authentication to define the Windows domain which is accessed. Initially set by new(domain) and defaults to the server's name.

Exchanging Information

Protocol [internals]

The follow methods handle protocol internals, and should not be used by a normal user of this class.

$obj->appendMessage(MESSAGE, FOLDERNAME)

Write the message to the server.


Create an object of CLASS, which extends the Mail::IMAPClient manpage.


Remove one folder.


Command the server to delete for real all messages which are flagged to be deleted.


Get some INFO about the MESSAGES from the server. The specified messages shall extend Mail::Box::Net::Message, Returned is a list of hashes, each info about one result. The contents of the hash differs per INFO, but at least a message field will be present, to relate to the message in question.

The right folder should be selected before this method is called. When the connection was lost, undef is returned. Without any messages, and empty array is returned. The retrieval is done by Mail::IMAPClient method fetch(), which is then parsed.



In SCALAR context, a hash with labels is returned. In LIST context, pairs are returned.

The WHAT parameter can be 'SET', 'CLEAR', or 'REPLACE'. With the latter, all standard imap flags do not appear in the list will be ignored: their value may either by set or cleared. See getFlags()

Unknown flags in LIST are stripped from their backslash and lower-cased. For instance, '\SomeWeirdFlag' will become `someweirdflag => 1'.

Example: translating IMAP4 flags into MailBox flags

 my @flags  = ('\Seen', '\Flagged');
 my $labels = Mail::Transport::IMAP4->flags2labels(SET => @flags);


Be sure that the specific FOLDER is the current one selected. If the folder is already selected, no IMAP traffic will be produced. The imap connection is returned on succes


Returns a list of folder names which are sub-folders of the specified FOLDERNAME. Without FOLDERNAME, the top-level foldernames are returned.

$obj->getFields(UID, NAME, [NAME, ...])

Get the records with the specified NAMES from the header. The header fields are returned as list of Mail::Message::Field::Fast objects. When the name is ALL, the whole header is returned.

$obj->getFlags(FOLDER, ID)

Returns the values of all flags which are related to the message with the specified ID. These flags are translated into the names which are standard for the MailBox suite.

A HASH is returned. Names which do not appear will also provide a value in the returned: the negative for the value is it was present.


Returns the whole text of the specified message: the head and the body.


Returns a list of UIDs which are defined by the IMAP server.


Returns the object which implements the IMAP4 protocol, an instance of a Mail::IMAPClient, which is logged-in and ready to use.

If the contact to the server was still present or could be established, an Mail::IMAPClient object is returned. Else, undef is returned and no further actions should be tried on the object.



Convert MailBox labels into IMAP flags. Returned is a string. Unsupported labels are ignored.


Returns all predefined flags as list.


Establish a new connection to the IMAP4 server, using username and password.

$obj->setFlags(ID, LABEL, VALUE, [LABEL, VALUE], ...)

Change the flags on the message which are represented by the label. The value which can be related to the label will be lost, because IMAP only defines a boolean value, where MailBox labels can contain strings.

Returned is a list of LABEL=>VALUE pairs which could not be send to the IMAP server. These values may be cached in a different way.

Error handling


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


Mail::Transport::IMAP4->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])

See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage

$obj->log([LEVEL [,STRINGS]])

Mail::Transport::IMAP4->log([LEVEL [,STRINGS]])

See Error handling in the Mail::Reporter manpage



See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage


See Error handling in the Mail::Reporter manpage



The connection is cleanly terminated when the program is terminated.


See Cleanup in the Mail::Reporter manpage


Error: Cannot connect to $host:$port for IMAP4: $!

Error: IMAP cannot connect to $host: $@

Notice: IMAP4 authenication $mechanism to $host:$port successful

Error: IMAP4 requires a username and password

Error: IMAP4 username $username requires a password

Error: Package $package does not implement $method.

Fatal error: the specific package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package.

Error: module Authen::NTLM is not installed

You try to establish an IMAP4 connection which explicitly uses NTLM authentication, but the optional Authen::NTLM, which implements this is not installed on your system.


See the MailBox website at for more details.


Distribution version 2.059. Written by Mark Overmeer ( See the ChangeLog for other contributors.

Copyright (c) 2001-2003 by the author(s). All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

 Mail::Transport::IMAP4 - proxy to Mail::IMAPClient