Mail::Transport::Dbx - Parse Outlook Express mailboxes
use Mail::Transport::Dbx;
my $dbx = eval { Mail::Transport::Dbx->new("box.mbx") };
die $@ if $@;
for my $i (0 .. $dbx->msgcount - 1) {
my $msg = $dbx->get($i);
print $msg->subject;
...
}
# more convenient
for my $msg ($dbx->emails) {
print $msg->subject;
...
}
Read dbx files (mailbox files of Outlook Express)
Mail::Transport::Dbx gives you platform independent access to Outlook Express'
dbx files. Extract subfolders, messages etc. from those or use it to convert
dbx archives into a more portable format (such as standard mbox format).
It relies on LibDBX to do its job. The bad news: LibDBX knows
nothing about the endianness of your machine so it does not work on
big-endian machines such as Macintoshs or SUNs. The good news: I made the
appropriate patches so that it in fact does work even on machines with the
'wrong' byteorder (exception: machines with an even odder byteorder such as
Crays are not suppored; exception from the exception: If you buy me a Cray
I'll promise to fix it. :-).
You have to understand the structure of .dbx files to make proper
use of this module. Outlook Express keeps a couple of those files on your
harddisk. For instance:
Folders.dbx
folder1.dbx
comp.lang.perl.misc.dbx
The nasty thing about that is that there are really two different
kinds of such files: One that contains the actual messages and one that
merely holds references to other .dbx files. Folders.dbx could be
considered the toplevel file since it lists all other available .dbx files.
As for folder1.dbx and comp.lang.perl.misc.dbx you can't yet know whether
they contain messages or subfolders (though comp.lang.perl.misc.dbx probably
contains newsgroup messages that are treated as mere emails).
Fortunately this module gives you the information you need. A
common approach would be the following:
1) create a new Mail::Transport::Dbx object from "Folders.dbx"
2) iterate over its items using the get() method
2.1 if it returns a Mail::Transport::Dbx::Email
=> a message
2.2 if it returns a Mail::Transport::Dbx::Folder
=> a folder
3) if message
3.1 call whatever method from Mail::Transport::Dbx::Email
you need
4) if folder
4.1 call whatever method from Mail::Transport::Dbx::Folder
you need
OR
4.2 call dbx() on it to create a new Mail::Transport::Dbx
object
4.2.1 if dbx() returned something defined
=> rollback to item 2)
The confusing thing is that .dbx files may contain references to
other folders that don't really exist! If Outlook Express was used a
newsclient this is a common scenario since Folders.dbx lists all
newsgroups as separate
"Mail::Transport::Dbx::Folder" objects no
matter whether you are subscribed to any of those or not. So in essence
calling "dbx()" on a folder will only
return a new object if the corresponding .dbx file exists.
The following are methods for Mail::Transport::Dbx objects:
- new(filename)
- new(filehandle-ref)
- Passed either a string being the filename or an already opened and
readable filehandle ref, "new()" will
construct a Mail::Transport::Dbx object from that.
This happens regardless of whether you open an ordinary dbx
file or the special Folders.dbx file that contains an overview
over all available dbx subfolders.
If opening fails for some reason your program will instantly
"die()" so be sure to wrap the
constructor into an "eval()" and check
for $@:
my $dbx = eval { Mail::Transport::Dbx->new( "file.dbx" ) };
die $@ if $@;
Be careful with using a filehandle, though. On Windows, you
might need to use "binmode()" on your
handle or otherwise the stream from your dbx file might get
corrupted.
- msgcount
- Returns the number of items stored in the dbx structure. If you previously
opened Folders.dbx "msgcount()" returns
the number of subfolders in it. Otherwise it returns the number of
messages. "msgcount() - 1" is the index
of the last item.
- emails
- In list context this method returns all emails contained in the file. In
boolean (that is, scalar) context it returns a true value if the file
contains emails and false if it contains subfolders.
if ($dbx->emails) {
print "I contain emails";
} else {
print "I contain subfolders";
}
This is useful for iterations:
for my $msg ($dbx->emails) {
...
}
- subfolders
- In list context this method returns all subfolders of the current file as
"Mail::Transport::Dbx::Folder" objects.
In boolean (scalar) context it returns true of the file contains
subfolders and false if it contains emails.
Remember that you still have to call
"dbx()" on these subfolders if you
want to do something useful with them:
for my $sub ($dbx->subfolders) {
if (my $d = $sub->dbx) {
# $d now a proper Mail::Transport::Dbx object
# with content
} else {
print "Subfolder referenced but non-existent";
}
}
- get(n)
- Get the item at the n-th position. First item is at position 0.
"get()" is actually a factory method so
it either returns a
"Mail::Transport::Dbx::Email" or
"Mail::Transport::Dbx::Folder" object.
This depends on the folder you call this method upon:
my $dbx = Mail::Transport::Dbx->new( "Folders.dbx" );
my $item = $dbx->get(0);
$item will now definitely be a
"Mail::Transport::Dbx::Folder" object
since Folders.dbx doesn't contain emails but references to
subfolders.
You can use the "is_email()"
and "is_folder()" method to check for
its type:
if ($item->is_email) {
print $item->subject;
} else {
# it's a subfolder
...
}
On an error, this method returns an undefined value. Check
"$dbx->errstr" to find out what
went wrong.
- errstr
- Whenever an error occurs, "errstr()"
will contain a string giving you further help what went wrong.
WARNING: Internally it relies on a global variable so
all objects will have the same error-string! That means it only makes
sense to use it after an operation that potentially raises an error:
# example 1
my $dbx = Mail::Transport::Dbx->new("box.dbx")
or die Mail::Transport::Dbx->errstr;
# example 2
my $msg = $dbx->get(5) or print $dbx->errstr;
- error
- Similar to "errstr()", only that it will
return an error code. See "Exportable constants/Error-Codes"
under "EXPORT" for codes that can be returned.
The following are the methods for
Mail::Transport::Dbx::Email objects:
- as_string
- Returns the whole message (header and body) as one large string.
Note that the string still contains the raw newlines as used
by DOSish systems (\015\012). If you want newlines to be represented in
the native format of your operating system, use the following:
my $email = $msg->as_string;
$email =~ s/\015\012/\n/g;
On Windows this is a no-op so you can ommit this step.
Especially for news-articles this method may return
"undef". This always happens when the
particular articles was only partially downloaded (that is, only header
retrieved from the newsserver). There is no way to retrieve this header
literally with "header". Methods like
"subject" etc. however do work.
- header
- Returns the header-portion of the whole email.
With respect to newlines the same as described under
"as_string()" applies.
Returns "undef" under the
same circumstances as "as_string".
- body
- Returns the body-portion of the whole email.
With respect to newlines the same as described under
"as_string()" applies.
Returns "undef" under the
same circumstances as "as_string".
- subject
- Returns the subject of the email as a string.
- psubject
- Returns the processed subject of the email as a string. 'Processed' means
that additions such as "Re:" etc. are cut off.
- msgid
- Returns the message-id of the message as a string.
- parents_ids
- Returns the message-ids of the parent messages as a string.
- sender_name
- Returns the name of the sender of this email as a string.
- sender_address
- Returns the address of the sender of this email as a string.
- recip_name
- Returns the name of the recipient of this email as a string. This might be
your name. ;-)
- recip_address
- Returns the address of the recipient of this email as a string.
- oe_account_name
- Returns the Outlook Express account name this message was retrieved with
as a string.
- oe_account_num
- Outlook Express accounts also seem to have a numerical representation.
This method will return this as a string (something like
"0000001").
- fetched_server
- Returns the name of the POP server that this message was retrieved from as
a string.
- rcvd_localtime
- This is the exact duplicate of Perl's builtin
"localtime()" applied to the date this
message was received. It returns a string in scalar context and a list
with nine elements in list context. See 'perldoc -f localtime' for
details.
- rcvd_gmtime
- Same as "rcvd_localtime()" but returning
a date conforming to GMT.
- date_received( [format, [len, [gmtime]]] )
- This method returns the date this message was received by you as a string.
The date returned is calculated according to
"localtime()".
Without additional arguments, the string returned looks
something like
Sun Apr 14 02:27:57 2002
The optional first argument is a string describing the format
of the date line. It is passed unchanged to
strftime(3). Please consult your system's
documentation for strftime(3) to see how such a
string has to look like. The default string to render the date is
"%a %b %e
%H:%M:%S %Y".
The optional second argument is the max string length to be
returned by "date_received()". This
parameter is also passed unaltered to
"strftime()". This method uses 25 as
default
The third argument can be set to a true value if you rather
want to get a date in GMT. So if you want to get the GMT of the date but
want to use the default rendering settings, you will have to provide
them yourself:
print $msg->date_received("%a %b %e %H:%M:%S %Y", 25, 1);
- is_seen
- Returns a true value if this message has already been seen. False
otherwise.
- is_email
- Always returns true for this kind of object.
- is_folder
- Always returns false for this kind of object.
The following methods exist for
Mail::Transport::Dbx::Folder objects:
- dbx
- This is a convenience method. It creates a
"Mail::Transport::Dbx" object from the
folder object. If the folder is only mentioned but not physically existing
on your hard-drive (either because you deleted the .dbx file or it was
actually never there which especially happens for newsgroup files)
"dbx" returns an undefined value.
Please read "DESCRIPTION" again to learn why
"dbx()" can return an undefined
value.
- num
- The index number of this folder. This is the number you passed to
"$dbx->get()" to retrieve this
folder.
- type
- According to libdbx.h this returns one of
"DBX_TYPE_FOLDER" or
"DBX_TYPE_EMAIL". Use it to check
whether the folder contains emails or other folders.
- name
- The name of the folder.
- file
- The filename of the folder. Use this, to create a new
"Mail::Transport::Dbx" object:
# $folder is a Mail::Transport::Dbx::Folder object
my $new_dbx = Mail::Transport::Dbx->new( $folder->file );
Consider using the "dbx()"
method instead.
This method returns an undefined value if there is no .dbx
file belonging to this folder.
- id
- Numerical id of the folder. Not sure what this is useful for.
- parent_id
- Numerical id of the parent's folder.
- folder_path
- Returns the full folder name of this folder as a list of path elements.
It's then in your responsibility to join them together by using a
delimiter that doesn't show up in any of the elements. ;-)
print join("/", $_->folder_path), "\n" for $dbx->subfolders;
# could for instance produce a long list, such as:
Outlook Express/news.rwth-aachen.de/de.comp.software.announce
Outlook Express/news.rwth-aachen.de/de.comp.software.misc
...
Outlook Express/Lokale Ordner/test/test1
Outlook Express/Lokale Ordner/test
Outlook Express/Lokale Ordner/Entwürfe
Outlook Express/Lokale Ordner/Gelöschte Objekte
Outlook Express/Lokale Ordner/Gesendete Objekte
Outlook Express/Lokale Ordner/Postausgang
Outlook Express/Lokale Ordner/Posteingang
Outlook Express/Lokale Ordner
Outlook Express/Outlook Express
Note that a slash (as any other character) might not be a safe
choice as it could show up in a folder name.
None by default.
If you intend to use any of the following constants, you have to import them
when "use()"ing the module. You can import
them all in one go thusly:
use Mail::Transport::Dbx qw(:all);
Or you import only those you need:
use Mail::Transport::Dbx qw(DBX_TYPE_EMAIL DBX_TYPE_FOLDER);
- Error-Codes
- DBX_NOERROR
No error occured.
- DBX_BADFILE
Dbx file operation failed (open or close)
- DBX_DATA_READ
Reading of data from dbx file failed
- DBX_INDEXCOUNT
Index out of range
- DBX_INDEX_OVERREAD
Request was made for index reference greater than exists
- DBX_INDEX_UNDERREAD
Number of indexes read from dbx file is less than expected
- DBX_INDEX_READ
Reading of Index Pointer from dbx file failed
- DBX_ITEMCOUNT
Reading of Item Count from dbx file failed
- DBX_NEWS_ITEM
Item is a news item not an email
- Dbx types
- One of these is returned by
"$folder->type" so you can check
whether the folder contains emails or subfolders. Note that only
DBX_TYPE_EMAIL and DBX_TYPE_FOLDER are ever returned so even newsgroup
postings are of the type DBX_TYPE_EMAIL.
- Miscellaneous constants
- DBX_EMAIL_FLAG_ISSEEN
- DBX_FLAG_BODY
You can't retrieve the internal state of the objects using
"Data::Dumper" or so since
"Mail::Transport::Dbx" uses a blessed scalar
to hold a reference to the respective C structures. That means you have to use
the provided methods for each object. Call that strong encapsultion if you
need an euphemism for that.
There are currently no plans to implement write access to .dbx
files. I leave that up to the authors of libdbx.
Other than that I don't know yet of any. This, of course, has never actually
been a strong indication for the absence of bugs.
http://sourceforge.net/projects/ol2mbox hosts the libdbx package. It contains
the library backing this module along with a description of the file format
for .dbx files.
Tassilo von Parseval, <tassilo.von.parseval@rwth-aachen.de>
Copyright 2003-2005 by Tassilo von Parseval
This library is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
Hey! The above document had some coding errors, which are explained
below:
- Around line 450:
- Non-ASCII character seen before =encoding in 'Ordner/Entwürfe'.
Assuming CP1252