Mail::Box::POP3 - handle POP3 folders as client


NAME

Mail::Box::POP3 - handle POP3 folders as client


INHERITANCE

 Mail::Box::POP3
   is a Mail::Box::Net
   is a Mail::Box
   is a Mail::Reporter


SYNOPSIS

 use Mail::Box::POP3;
 my $folder = new Mail::Box::POP3 folder => $ENV{MAIL}, ...;


DESCRIPTION

Maintain a folder which has its messages stored on a remote server. The communication between the client application and the server is implemented using the POP3 protocol. This class uses Mail::Transport::POP3 to hide the transport of information, and focusses solely on the correct handling of messages within a POP3 folder.


OVERLOADED

overload: ``''

See OVERLOADED in the Mail::Box manpage

overload: @{}

See OVERLOADED in the Mail::Box manpage

overload: cmp

See OVERLOADED in the Mail::Box manpage


METHODS

Constructors

Mail::Box::POP3->new(OPTIONS)

For authentications, you have three choices: specify a foldername which resembles an URL, or specify a pop-client object, or separate options for user, password, pop-server and server-port.

 Option             Defined in       Default                                                         
 access             L<Mail::Box>     C<'r'>                                                          
 authenticate                        C<'AUTO'>                                                       
 body_delayed_type  L<Mail::Box>     L<Mail::Message::Body::Delayed|Mail::Message::Body::Delayed>    
 body_type          L<Mail::Box>     L<Mail::Message::Body::Lines|Mail::Message::Body::Lines>        
 coerce_options     L<Mail::Box>     C<[]>                                                           
 create             L<Mail::Box>     <not applicable>                                                
 extract            L<Mail::Box>     C<10240>                                                        
 field_type         L<Mail::Box>     undef                                                           
 fix_headers        L<Mail::Box>     <false>                                                         
 folder             L<Mail::Box>     <not applicable>                                                
 folderdir          L<Mail::Box>     <not used>                                                      
 head_delayed_type  L<Mail::Box>     L<Mail::Message::Head::Delayed|Mail::Message::Head::Delayed>    
 head_type          L<Mail::Box>     L<Mail::Message::Head::Complete|Mail::Message::Head::Complete>  
 keep_dups          L<Mail::Box>     <false>                                                         
 lock_file          L<Mail::Box>     undef                                                           
 lock_timeout       L<Mail::Box>     1 hour                                                          
 lock_type          L<Mail::Box>     C<'NONE'>                                                       
 lock_wait          L<Mail::Box>     10 seconds                                                      
 locker             L<Mail::Box>     undef                                                           
 log                L<Mail::Reporter>  C<'WARNINGS'>                                                   
 manager            L<Mail::Box>     undef                                                           
 message_type       L<Mail::Box>     L<Mail::Box::POP3::Message|Mail::Box::POP3::Message>            
 multipart_type     L<Mail::Box>     L<Mail::Message::Body::Multipart|Mail::Message::Body::Multipart>
 password           L<Mail::Box::Net>  undef                                                           
 pop_client                          undef                                                           
 remove_when_empty  L<Mail::Box>     <false>                                                         
 save_on_exit       L<Mail::Box>     <true>                                                          
 server_name        L<Mail::Box::Net>  undef                                                           
 server_port        L<Mail::Box::Net>  110                                                             
 trace              L<Mail::Reporter>  C<'WARNINGS'>                                                   
 trusted            L<Mail::Box>     <false>                                                         
 username           L<Mail::Box::Net>  undef

. access MODE

. authenticate 'LOGIN'|'APOP'|'AUTO'

POP3 can use two methods of authentication: the old LOGIN protocol, which transmits a username and password in plain text, and the newer APOP protocol which uses MD5 encryption. APOP is therefore much better, however not always supported by the server. With AUTO, first APOP is tried and if that fails LOGIN.

. body_delayed_type CLASS

. body_type CLASS|CODE

. coerce_options ARRAY

. create BOOLEAN

. extract INTEGER | CODE | METHOD | 'LAZY'|'ALWAYS'

. field_type CLASS

. fix_headers BOOLEAN

. folder FOLDERNAME

. folderdir DIRECTORY

. head_delayed_type CLASS

. head_type CLASS

. keep_dups BOOLEAN

. lock_file FILENAME

. lock_timeout SECONDS

. lock_type CLASS|STRING|ARRAY

. lock_wait SECONDS

. locker OBJECT

. log LEVEL

. manager MANAGER

. message_type CLASS

. multipart_type CLASS

. password STRING

. pop_client OBJECT

You may want to specify your own pop-client object. The object which is passed must extend Mail::Transport::POP3.

. remove_when_empty BOOLEAN

. save_on_exit BOOLEAN

. server_name HOSTNAME

. server_port INTEGER

. trace LEVEL

. trusted BOOLEAN

. username STRING

Example:

 my $url = 'pop3://user:password@pop.xs4all.nl'
 my $pop = Mail::Box::POP3->new($url);
 my $pop = $mgr->open(type => 'pop3',
    username => 'myname', password => 'mypassword',
    server_name => 'pop.xs4all.nl');

The folder

$obj->addMessage(MESSAGE)

It is impossible to write messages to the average POP3 server. There are extensions to the protocol which do permit it, however these are not implemented (yet, patches welcome).

undef is returned, and an error displayed. However, no complaint is given when the MESSAGE is undef itself.

 Option  Defined in    Default   
 share   L<Mail::Box>  <not used>

. share BOOLEAN

$obj->addMessages(MESSAGES)

As useless as addMessage(). The only acceptable call to this method is without any message.

Mail::Box::POP3->appendMessages(OPTIONS)

See The folder in the Mail::Box manpage

$obj->close(OPTIONS)

See The folder in the Mail::Box manpage

$obj->copyTo(FOLDER, OPTIONS)

See The folder in the Mail::Box manpage

$obj->delete(OPTIONS)

It is not possible to delete a POP3 folder remotely: the best we can do is remove all the messages in it... which is the action implemented here. A notice is logged about this.

 Option     Defined in    Default   
 recursive  L<Mail::Box>  <not used>

. recursive BOOLEAN

$obj->folderdir([DIRECTORY])

See METHODS in the Mail::Box::Net manpage

$obj->name

See The folder in the Mail::Box manpage

$obj->organization

See The folder in the Mail::Box manpage

$obj->size

See The folder in the Mail::Box manpage

$obj->type

See The folder in the Mail::Box manpage

$obj->update

NOT IMPLEMENTED YET

$obj->url

See The folder in the Mail::Box manpage

Folder flags

$obj->access

See Folder flags in the Mail::Box manpage

$obj->isModified

See Folder flags in the Mail::Box manpage

$obj->modified([BOOLEAN])

See Folder flags in the Mail::Box manpage

$obj->writable

See Folder flags in the Mail::Box manpage

The messages

$obj->current([NUMBER|MESSAGE|MESSAGE-ID])

See The messages in the Mail::Box manpage

$obj->find(MESSAGE-ID)

See The messages in the Mail::Box manpage

$obj->findFirstLabeled(LABEL, [BOOLEAN, [ARRAY-OF-MSGS]])

See The messages in the Mail::Box manpage

$obj->message(INDEX [,MESSAGE])

See The messages in the Mail::Box manpage

$obj->messageId(MESSAGE-ID [,MESSAGE])

See The messages in the Mail::Box manpage

$obj->messageIds

See The messages in the Mail::Box manpage

$obj->messages(['ALL',RANGE,'ACTIVE','DELETED',LABEL,!LABEL,FILTER])

See The messages in the Mail::Box manpage

$obj->nrMessages(OPTIONS)

See The messages in the Mail::Box manpage

$obj->scanForMessages(MESSAGE, MESSAGE-IDS, TIMESPAN, WINDOW)

See The messages in the Mail::Box manpage

Sub-folders

$obj->listSubFolders(OPTIONS)

Mail::Box::POP3->listSubFolders(OPTIONS)

The standard POP3 protocol does not support sub-folders, so an empty list will be returned in any case.

 Option      Defined in       Default              
 check       L<Mail::Box>     <false>              
 folder      L<Mail::Box>     <from calling object>
 folderdir   L<Mail::Box>     <from folder>        
 skip_empty  L<Mail::Box>     <false>

. check BOOLEAN

. folder FOLDERNAME

. folderdir DIRECTORY

. skip_empty BOOL

$obj->nameOfSubFolder(SUBNAME, [PARENTNAME])

Mail::Box::POP3->nameOfSubFolder(SUBNAME, [PARENTNAME])

See Sub-folders in the Mail::Box manpage

$obj->openRelatedFolder(OPTIONS)

See Sub-folders in the Mail::Box manpage

$obj->openSubFolder(OPTIONS)

It is not possible to open a sub-folder for a POP3 folder, because that is not supported by the official POP3 protocol. In any case, undef is returned to indicate a failure.

$obj->topFolderWithMessages

Mail::Box::POP3->topFolderWithMessages

See Sub-folders in the Mail::Box manpage

Internals

$obj->coerce(MESSAGE, OPTIONS)

See Internals in the Mail::Box manpage

$obj->create(FOLDER, OPTIONS)

Mail::Box::POP3->create(FOLDER, OPTIONS)

It is not possible to create a new folder on a POP3 server. This method will always return false.

 Option     Defined in    Default   
 folderdir  L<Mail::Box>  <not used>

. folderdir DIRECTORY

$obj->determineBodyType(MESSAGE, HEAD)

See Internals in the Mail::Box manpage

Mail::Box::POP3->foundIn([FOLDERNAME], OPTIONS)

See Internals in the Mail::Box manpage

$obj->getHead(MESSAGE)

Read the header for the specified message from the remote server.

$obj->getHeadAndBody(MESSAGE)

Read all data for the specified message from the remote server.

$obj->lineSeparator([STRING|'CR'|'LF'|'CRLF'])

See Internals in the Mail::Box manpage

$obj->locker

See Internals in the Mail::Box manpage

$obj->popClient

Returns the pop client object. This does not establish the connection.

$obj->read(OPTIONS)

See Internals in the Mail::Box manpage

$obj->readMessages(OPTIONS)

See Internals in the Mail::Box manpage

$obj->storeMessage(MESSAGE)

See Internals in the Mail::Box manpage

$obj->toBeThreaded(MESSAGES)

See Internals in the Mail::Box manpage

$obj->toBeUnthreaded(MESSAGES)

See Internals in the Mail::Box manpage

$obj->updateMessages(OPTIONS)

See Internals in the Mail::Box manpage

$obj->write(OPTIONS)

See Internals in the Mail::Box manpage

$obj->writeMessages(OPTIONS)

 Option    Defined in    Default   
 messages  L<Mail::Box>  <required>

. messages ARRAY

Other methods

$obj->timespan2seconds(TIME)

Mail::Box::POP3->timespan2seconds(TIME)

See Other methods in the Mail::Box manpage

Error handling

$obj->AUTOLOAD

See Error handling in the Mail::Reporter manpage

$obj->addReport(OBJECT)

See Error handling in the Mail::Reporter manpage

$obj->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])

Mail::Box::POP3->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])

See Error handling in the Mail::Reporter manpage

$obj->errors

See Error handling in the Mail::Reporter manpage

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

Mail::Box::POP3->log([LEVEL [,STRINGS]])

See Error handling in the Mail::Reporter manpage

$obj->logPriority(LEVEL)

Mail::Box::POP3->logPriority(LEVEL)

See Error handling in the Mail::Reporter manpage

$obj->logSettings

See Error handling in the Mail::Reporter manpage

$obj->notImplemented

See Error handling in the Mail::Reporter manpage

$obj->report([LEVEL])

See Error handling in the Mail::Reporter manpage

$obj->reportAll([LEVEL])

See Error handling in the Mail::Reporter manpage

$obj->trace([LEVEL])

See Error handling in the Mail::Reporter manpage

$obj->warnings

See Error handling in the Mail::Reporter manpage

Cleanup

$obj->DESTROY

See Cleanup in the Mail::Box manpage

$obj->inGlobalDestruction

See Cleanup in the Mail::Reporter manpage


DIAGNOSTICS

Error: Cannot create POP3 client for $name.

The connection to the POP3 server cannot be established. You may see more, related, error messages about the failure.

Error: Cannot find head back for $uidl on POP3 server $name.

The server told to have this message, but when asked for its headers, no single line was returned. Did the message get destroyed?

Error: Cannot read body for $uidl on POP3 server $name.

The message's headers are retreived from the server, but the body seems to be lost. Did the message get destroyed between reading the header and reading the body?

Warning: Changes not written to read-only folder $self.

You have opened the folder read-only --which is the default set by new(access)--, made modifications, and now want to close it. Set close(force) if you want to overrule the access mode, or close the folder with close(write) set to NEVER.

Error: Copying failed for one message.

For some reason, for instance disc full, removed by external process, or read-protection, it is impossible to copy one of the messages. Copying will proceed for the other messages.

Error: Destination folder $name is not writable.

The folder where the messages are copied to is not opened with write access (see new(access)). This has no relation with write permission to the folder which is controled by your operating system.

Warning: Different messages with id $msgid.

The message id is discovered more than once within the same folder, but the content of the message seems to be different. This should not be possible: each message must be unique.

Error: Folder $name is opened read-only

You can not write to this folder unless you have opened the folder to write or append with new(access), or the force option is set true.

Error: Invalid timespan '$timespan' specified.

The string does not follow the strict rules of the time span syntax which is permitted as parameter.

Warning: Message $uidl on POP3 server $name disappeared.

The server indicated the existence of this message before, however it has no information about the message anymore.

Warning: Message-id '$msgid' does not contain a domain.

According to the RFCs, message-ids need to contain a unique random part, then an @, and then a domain name. This is made to avoid the creation of two messages with the same id. The warning emerges when the @ is missing from the string.

Warning: POP3 folders cannot be deleted.

Each user has only one POP3 folder on a server. This folder is created and deleted by the server's administrator only.

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: Unable to create subfolder $name of $folder.

The copy includes the subfolders, but for some reason it was not possible to copy one of these. Copying will proceed for all other sub-folders.

Error: Update of $nr messages ignored for POP3 folder $name.

The standard POP3 implementation does not support writing from client back to the server. Therefore, modifications may be lost.

Error: Writing folder $name failed

For some reason (you probably got more error messages about this problem) it is impossible to write the folder, although you should because there were changes made.

Error: You cannot write a message to a pop server (yet)

Some extensions to the POP3 protocol do permit writing messages to the server, but the standard protocol only implements retreival. Feel invited to extend our implementation with writing.


DETAILS

How POP3 folders work

Rfc1939 defines how POP3 works. POP3 is a really simple protocol to receive messages from a server to a user's client. POP3 is also really limited: it can only be used to fetch messages, but has not many ways to limit the amount of network traffic, like the IMAP4 protocol has.

One POP3 account represents only one folder: there is no way of sub-folders in POP3. POP3 doesn't support writing (except for some message status flags).

This implementation

The protocol specifics are implemented in Mail::Transport::POP3, written by Liz Mattijsen. That module does not use any of the other POP3 modules available on CPAN for the reason that MailBox tries to be smarter: it is capable of re-establishing broken POP3 connection when the server supports UIDs.

The implementation has shown to work with many different POP servers. In the test directory of the distribution, you will find a small server implementation, which is used to test the client.


REFERENCES

See the MailBox website at http://perl.overmeer.net/mailbox/ for more details.


COPYRIGHTS

Distribution version 2.059. Written by Mark Overmeer (mark@overmeer.net) 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::Box::POP3 - handle POP3 folders as client