Mail::Box::File - handle file-based folders


NAME

Mail::Box::File - handle file-based folders


INHERITANCE

 Mail::Box::File
   is a Mail::Box
   is a Mail::Reporter
 Mail::Box::File is extended by
   Mail::Box::Dbx
   Mail::Box::Mbox


SYNOPSIS


DESCRIPTION

Mail::Box::File is the base-class for all file-based folders: folders which bundle multiple messages into one single file. Usually, these messages are separated by a special line which indicates the start of the next one.


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::File->new(OPTIONS)

 Option             Defined in       Default                                                         
 access             L<Mail::Box>     C<'r'>                                                          
 body_delayed_type  L<Mail::Box>     L<Mail::Message::Body::Delayed|Mail::Message::Body::Delayed>    
 body_type                           <see description>                                               
 coerce_options     L<Mail::Box>     C<[]>                                                           
 create             L<Mail::Box>     <false>                                                         
 extract            L<Mail::Box>     C<10240>                                                        
 field_type         L<Mail::Box>     undef                                                           
 fix_headers        L<Mail::Box>     <false>                                                         
 folder             L<Mail::Box>     C<$ENV{MAIL}>                                                   
 folderdir          L<Mail::Box>     C<$ENV{HOME}.'/Mail'>                                           
 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_extension                      C<'.lock'>                                                      
 lock_file          L<Mail::Box>     <foldername>.<lock-extension>                                   
 lock_timeout       L<Mail::Box>     1 hour                                                          
 lock_type          L<Mail::Box>     L<Mail::Box::Locker::DotLock|Mail::Box::Locker::DotLock>        
 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::File::Message|Mail::Box::File::Message>            
 multipart_type     L<Mail::Box>     L<Mail::Message::Body::Multipart|Mail::Message::Body::Multipart>
 remove_when_empty  L<Mail::Box>     <true>                                                          
 save_on_exit       L<Mail::Box>     <true>                                                          
 trace              L<Mail::Reporter>  C<'WARNINGS'>                                                   
 trusted            L<Mail::Box>     <depends on folder location>                                    
 write_policy                        undef

. access MODE

. body_delayed_type CLASS

. body_type CLASS|CODE

The default body_type option for File folders, which will cause messages larger than 10kB to be stored in files and smaller files in memory, is implemented like this:

 sub determine_body_type($$)
 {   my $head = shift;
     my $size = shift || 0;
     'Mail::Message::Body::'
        . ($size > 10000 ? 'File' : 'Lines');
 }

. 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_extension FILENAME|STRING

When the dotlock locking mechanism is used, the lock is created with a hardlink to the folder file. For Mail::Box::File type of folders, this file is by default named as the folder-file itself followed by .lock. For example: the Mail/inbox folder file will have a hardlink made as Mail/inbox.lock.

You may specify an absolute filename, a relative (to the folder's directory) filename, or an extension (preceded by a dot). So valid examples are:

 .lock        # appended to the folder's filename
 my_own_lockfile.test   # full filename, same dir
 /etc/passwd            # somewhere else

When the program runs with less priviledges (as normal user), often the default inbox folder can not be locked with the lockfile name which is produced by default.

. 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

. remove_when_empty BOOLEAN

. save_on_exit BOOLEAN

. trace LEVEL

. trusted BOOLEAN

. write_policy 'REPLACE'|'INPLACE'|undef

Sets the default write policy, as default for a later call to write(policy). With undef, the best policy is autodetected.

The folder

$obj->addMessage(MESSAGE, OPTIONS)

See The folder in the Mail::Box manpage

$obj->addMessages(MESSAGE [, MESSAGE, ...])

See The folder in the Mail::Box manpage

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

Appending messages to a file based folder which is not opened is a little risky. In practice, this is often done without locking the folder. So, an other application may write to the folder at the same time... :( Hopefully, all goes fast enough that the chance on collition is small.

 Option    Defined in       Default   
 folder    L<Mail::Box>     <required>
 message   L<Mail::Box>     undef     
 messages  L<Mail::Box>     undef     
 share     L<Mail::Box>     <false>

. folder FOLDERNAME

. message MESSAGE

. messages ARRAY-OF-MESSAGES

. share BOOLEAN

$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)

See The folder in the Mail::Box manpage

$obj->filename

Returns the filename for this folder, which may be an absolute or relative path to the file.

Example:

 print $folder->filename;

$obj->folderdir([DIRECTORY])

See The folder in the Mail::Box 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(OPTIONS)

See The folder in the Mail::Box manpage

$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::File->listSubFolders(OPTIONS)

See Sub-folders in the Mail::Box manpage

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

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

See Sub-folders in the Mail::Box manpage

$obj->openRelatedFolder(OPTIONS)

See Sub-folders in the Mail::Box manpage

$obj->openSubFolder(SUBNAME, OPTIONS)

See Sub-folders in the Mail::Box manpage

$obj->topFolderWithMessages

Mail::Box::File->topFolderWithMessages

See Sub-folders in the Mail::Box manpage

Internals

$obj->coerce(MESSAGE, OPTIONS)

See Internals in the Mail::Box manpage

$obj->create(FOLDERNAME, OPTIONS)

Mail::Box::File->create(FOLDERNAME, OPTIONS)

 Option     Defined in    Default
 folderdir  L<Mail::Box>  undef

. folderdir DIRECTORY

$obj->determineBodyType(MESSAGE, HEAD)

See Internals in the Mail::Box manpage

$obj->folderToFilename(FOLDERNAME, FOLDERDIR, [SUBEXT])

Mail::Box::File->folderToFilename(FOLDERNAME, FOLDERDIR, [SUBEXT])

Translate a folder name into a filename, using the FOLDERDIR value to replace a leading =. SUBEXT is only used for MBOX folders.

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

See Internals in the Mail::Box manpage

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

See Internals in the Mail::Box manpage

$obj->locker

See Internals in the Mail::Box manpage

$obj->messageCreateOptions([TYPE, CONFIG])

Returns a key-value list of options to be used each time a new message is read from a file. The list is preceeded by the TYPE of message which has to be created.

This data is used by readMessages() and updateMessages(). With TYPE and CONFIG, a new configuration is set.

$obj->moveAwaySubFolder(DIRECTORY, EXTENSION)

The DIRECTORY is renamed by appending the EXTENSION, which defaults to ".d", to make place for a folder file on that specific location. false is returned if this failed.

$obj->parser

Create a parser for this mailbox. The parser stays alive as long as the folder is open.

$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)

For file based folders, the file handle stays open until the folder is closed. Update is therefore rather simple: move to the end of the last known message, and continue reading...

$obj->write(OPTIONS)

 Option        Defined in       Default
 force         L<Mail::Box>     <false>
 policy                         undef  
 save_deleted  L<Mail::Box>     <false>

. force BOOLEAN

. policy 'REPLACE'|'INPLACE'|undef

In what way will the mail folder be updated. If not specified during the write, the value of the new(write_policy) at folder creation is taken.

Valid values:

$obj->writeMessages(OPTIONS)

See Internals in the Mail::Box manpage

File based folders

File based folders maintain a folder (a set of messages) in one single file. The advantage is that your folder has only one single name, which speeds-up access to all messages at once.

The disadvantage over directory based folder (see Mail::Box::Dir) is that you have to construct some means to keep all message apart, for instance by adding a message separator, and this will cause problems. Where access to all messages at once is faster in file based folders, access to a single message is (much) slower, because the whole folder must be read.

File based folders

File based folders maintain a folder (a set of messages) in one single file. The advantage is that your folder has only one single name, which speeds-up access to all messages at once.

The disadvantage over directory based folder (see Mail::Box::Dir) is that you have to construct some means to keep all message apart, for instance by adding a message separator, and this will cause problems. Where access to all messages at once is faster in file based folders, access to a single message is (much) slower, because the whole folder must be read.

Other methods

$obj->timespan2seconds(TIME)

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

See Error handling in the Mail::Reporter manpage

$obj->logPriority(LEVEL)

Mail::Box::File->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 append messages to folder file $filename: $!

Appending messages to a not-opened file-organized folder may fail when the operating system does not allow write access to the file at hand.

Error: Cannot create directory $dir for folder $name.

While creating a file-organized folder, at most one level of directories is created above it. Apparently, more levels of directories are needed, or the operating system does not allow you to create the directory.

Error: Cannot create folder file $name: $!

The file-organized folder file cannot be created for the indicated reason. In common cases, the operating system does not grant you write access to the directory where the folder file should be stored.

Error: Cannot get a lock on $type folder $self.

A lock is required to get access to the folder. If no locking is needed, specify the NONE lock type.

Error: Cannot move away sub-folder $dir

Warning: Cannot remove folder $name file $filename: $!

Writing an empty folder will usually cause that folder to be removed, which fails for the indicated reason. new(remove_when_empty)

Warning: Cannot remove folder $name file $filename: $!

Writing an empty folder will usually cause that folder to be removed, which fails for the indicated reason. new(remove_when_empty) controls whether the empty folder will removed; setting it to false (0) may be needed to avoid this message.

Error: Cannot replace $filename by $tempname, to update folder $name: $!

The replace policy wrote a new folder file to update the existing, but was unable to give the final touch: replacing the old version of the folder file for the indicated reason.

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: File too short to get write message $nr ($size, $need)

Mail::Box is lazy: it tries to leave messages in the folders until they are used, which saves time and memory usage. When this message appears, something is terribly wrong: some lazy message are needed for updating the folder, but they cannot be retreived from the original file anymore. In this case, messages can be lost.

This message does appear regularly on Windows systems when using the 'replace' write policy. Please help to find the cause, probably something to do with Windows incorrectly handling multiple filehandles open in the same file.

Warning: Folder $name file $filename is write-protected.

The folder is opened writable or for appending via new(access), but the operating system does not permit writing to the file. The folder will be opened read-only.

Error: Folder $name not deleted: not writable.

The folder must be opened with write access via new(access), otherwise removing it will be refused. So, you may have write-access according to the operating system, but that will not automatically mean that this delete method permits you to. The reverse remark is valid as well.

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-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.

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: Unable to update folder $self.

When a folder is to be written, both replace and inplace write policies are tried, If both fail, the whole update fails. You may see other, related, error messages to indicate the real problem.


DETAILS


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::File - handle file-based folders