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NAME

Net::IMAP::Client - Not so simple IMAP client library

SYNOPSIS

    use Net::IMAP::Client;

    my $imap = Net::IMAP::Client->new(

        server => 'mail.you.com',
        user   => 'USERID',
        pass   => 'PASSWORD',
        ssl    => 1,          # (use SSL? default no)
        port   => 993         # (but defaults are sane)

    ) or die "Could not connect to IMAP server";

    # everything's useless if you can't login
    $imap->login or
      die('Login failed: ' . $imap->last_error);

    # let's see what this server knows (result cached on first call)
    my $capab = $imap->capability;
       # or
    my $knows_sort = $imap->capability( qr/^sort/i );

    # get list of folders
    my @folders = $imap->folders;

    # get total # of messages, # of unseen messages etc. (fast!)
    my $status = $imap->status(@folders); # hash ref!

    # select folder
    $imap->select('INBOX');

    # get folder hierarchy separator (cached at first call)
    my $sep = $imap->separator;

    # fetch all message ids
    my @messages = $imap->search('ALL');

    # fetch all ID-s sorted by subject
    my $messages = $imap->search('ALL', 'SUBJECT');
       # or
    my @messages = $imap->search('ALL', [ 'SUBJECT' ]);

    # fetch ID-s that match criteria, sorted by subject and reverse date
    my $messages = $imap->search({
        FROM    => 'foo',
        SUBJECT => 'bar',
    }, [ 'SUBJECT', '^DATE' ]);

    # fetch message summaries (actually, a lot more)
    my @summaries = $imap->get_summaries([ @msg_ids ]);

    foreach (@summaries) {
        print $_->uid, $_->subject, $_->date, $_->rfc822_size;
        print join(', ', @{$_->from}); # etc.
    }

    # fetch full message
    my $data = $imap->get_rfc822_body($msg_id);
    print $$data; # it's reference to a scalar

    # fetch full messageS
    my @msgs = $imap->get_rfc822_body([ @msg_ids ]);
    print $$_ for (@msgs);

    # fetch single attachment (message part)
    my $data = $imap->get_part_body($msg_id, '1.2');

DESCRIPTION

Net::IMAP::Client provides methods to access an IMAP server. It aims to provide a simple and clean API, while employing a rigorous parser for IMAP responses in order to create Perl data structures from them. The code is simple, clean and extensible.

It started as an effort to improve Net::IMAP::Simple but then I realized that I needed to change a lot of code and API so I started it as a fresh module. Still, the design is influenced by Net::IMAP::Simple and I even stole a few lines of code from it ;-) (very few, honestly).

API REFERENCE

Unless otherwise specified, if a method fails it returns undef and you can inspect the error by calling $imap->last_error. For a successful call most methods will return a meaningful value but definitely not undef.

new( %args ) # constructor

    my $imap = Net::IMAP::Client->new(%args);

Pass to the constructor a hash of arguments that can contain:

- server (STRING)

Host name or IP of the IMAP server.

- user (STRING)

User ID (only "clear" login is supported for now!)

- pass (STRING)

Password

- ssl (BOOL, optional, default FALSE)

Pass a true value if you want to use IO::Socket::SSL

- uid_mode (BOOL, optional, default TRUE)

Wether to use UID command (see RFC2060). Recommended.

- socket (IO::Handle, optional)

If you already have a socket connected to the IMAP server, you can pass it here.

The constructor doesn't login to the IMAP server -- you need to call $imap->login for that.

last_error

Returns the last error from the IMAP server.

login( $user, $pass )

Login to the IMAP server. You can pass $user and $pass here if you wish; if not passed, the values used in constructor will be used.

Returns undef if login failed.

logout / quit

Send EXPUNGE and LOGOUT then close connection. quit is an alias for logout.

noop

"Do nothing" method that calls the IMAP "NOOP" command. It returns a true value upon success, undef otherwise.

This method fetches any notifications that the server might have for us and you can get them by calling $imap->notifications. See the notifications() method.

capability(), capability( qr/^SOMETHING/ )

With no arguments, returns an array of all capabilities advertised by the server. If you're interested in a certain capability you can pass a RegExp. E.g. to check if this server knows 'SORT', you can do this:

    if ($imap->capability(/^sort$/i)) {
        # speaks it
    }

This data is cached, the server will be only hit once.

select( $folder )

Selects the current IMAP folder. On success this method also records some information about the selected folder in a hash stored in $self->{FOLDERS}{$folder}. You might want to use Data::Dumper to find out exactly what, but at the time of this writing this is:

- messages

Total number of messages in this folder

- flags

Flags available for this folder (as array ref)

- recent

Total number of recent messages in this folder

- sflags

Various other flags here, such as PERMANENTFLAGS of UIDVALIDITY. You might want to take a look at RFC2060 at this point. :-p

This method is basically stolen from Net::IMAP::Simple.

status( $folder ), status( \@folders )

Returns the status of the given folder(s).

If passed an array ref, the return value is a hash ref mapping folder name to folder status (which are hash references in turn). If passed a single folder name, it returns the status of that folder only.

    my $inbox = $imap->status('INBOX');
    print $inbox->{UNSEEN}, $inbox->{MESSAGES};
    print Data::Dumper::Dumper($inbox);

    my $all = $imap->status($imap->folders);
    while (my ($name, $status) = each %$all) {
        print "$name : $status->{MESSAGES}/$status->{UNSEEN}\n";
    }

This method is designed to be very fast when passed multiple folders. It's a lot faster to call:

    $imap->status(\@folders);

than:

    $imap->status($_) foreach (@folders);

because it sends all the STATUS requests to the IMAP server before it starts receiving the answers. In my tests with my remote IMAP server, for 40 folders this method takes 0.6 seconds, compared to 6+ seconds when called individually for each folder alone.

separator

Returns the folder hierarchy separator. This is provided as a result of the following IMAP command:

    FETCH "" "*"

I don't know of any way to change this value on a server so I have to assume it's a constant. Therefore, this method caches the result and it won't hit the server a second time on subsequent calls.

folders

Returns a list of all folders available on the server. In scalar context it returns a reference to an array, i.e.:

    my @a = $imap->folders;
    my $b = $imap->folders;
    # now @a == @$b;

folders_more

Returns an hash reference containing more information about folders. It maps folder name to an hash ref containing the following:

  - flags -- folder flags (array ref; i.e. [ '\\HasChildren' ])
  - sep   -- one character containing folder hierarchy separator
  - name  -- folder name (same as the key -- thus redundant)

seq_to_uid( @sequence_ids )

I recomment usage of UID-s only (see uid_mode) but this isn't always possible. Even when uid_mode is on, the server will sometimes return notifications that only contain message sequence numbers. To convert these to UID-s you can use this method.

On success it returns an hash reference which maps sequence numbers to message UID-s. Of course, on failure it returns undef.

search( $criteria, $sort, $charset )

Executes the "SEARCH" or "SORT" IMAP commands (depending on wether $sort is undef) and returns the results as an array reference containing message ID-s.

Note that if you use $sort and the IMAP server doesn't have this capability, this method will fail. Use capability to investigate.

- $criteria

Can be a string, in which case it is passed literally to the IMAP command (which can be "SEARCH" or "SORT").

It can also be an hash reference, in which case keys => values are collected into a string and values are properly quotes, i.e.:

   { subject => 'foo',
     from    => 'bar' }

will translate to:

   'SUBJECT "foo" FROM "bar"'

which is a valid IMAP SEARCH query.

If you want to retrieve all messages (no search criteria) then pass 'ALL' here.

- $sort

Can be a string or an array reference. If it's an array, it will simply be joined with a space, so for instance passing the following is equivalent:

    'SUBJECT DATE'
    [ 'SUBJECT', 'DATE' ]

The SORT command in IMAP allows you to prefix a sort criteria with 'REVERSE' which would mean descending sorting; this module will allow you to prefix it with '^', so again, here are some equivalent constructs:

    'SUBJECT REVERSE DATE'
    'SUBJECT ^DATE'
    [ 'SUBJECT', 'REVERSE', 'DATE' ]
    [ 'subject', 'reverse date' ]
    [ 'SUBJECT', '^DATE' ]

It'll also uppercase whatever you passed here.

If you omit $sort (or pass undef) then this method will use the SEARCH command. Otherwise it uses the SORT command.

- $charset

The IMAP SORT recommendation [2] requires a charset declaration for SORT, but not for SEARCH. Interesting, huh?

Our module is a bit more paranoid and it will actually add charset for both SORT and SEARCH. If $charset is omitted (or undef) the it will default to "UTF-8", which, supposedly, is supported by all IMAP servers.

get_rfc822_body( $msg_id )

Fetch and return the full RFC822 body of the message. $msg_id can be a scalar but also an array of ID-s. If it's an array, then all bodies of those messages will be fetched and the return value will be a list or an array reference (depending how you call it).

Note that the actual data is returned as a reference to a scalar, to speed things up.

Examples:

    my $data = $imap->get_rfc822_body(10);
    print $$data;   # need to dereference it

    my @more = $imap->get_rfc822_body([ 11, 12, 13 ]);
    print $$_ foreach @more;

        or

    my $more = $imap->get_rfc822_body([ 11, 12, 13 ]);
    print $$_ foreach @$more;

get_part_body( $msg_id, $part_id )

Fetches and returns the body of a certain part of the message. Part ID-s look like '1' or '1.1' or '2.3.1' etc. (see RFC2060 [1], "FETCH Command").

Scalar reference

Note that again, this data is returned as a reference to a scalar rather than the scalar itself. This decision was taken purely to save some time passing around potentially large data from Perl subroutines.

Undecoded

One other thing to note is that the data is not undecoded. One simple way to decode it is use Email::MIME::Encodings, i.e.:

    use Email::MIME::Encodings;
    my $summary = $imap->get_summaries(10);
    my $part = $summary->get_subpart('1.1');
    my $body = $imap->get_part_body('1.1');
    my $cte = $part->transfer_encoding;  # Content-Transfer-Encoding
    $body = Email::MIME::Encodings::decode($cte, $$body);

    # and now you should have the undecoded (perhaps binary) data.

See get_summaries below.

get_parts_bodies( $msg_id, \@part_ids )

Similar to get_part_body, but this method is capable to retrieve more parts at once. It's of course faster than calling get_part_body for each part alone. Returns an hash reference which maps part ID to part body (the latter is a reference to a scalar containing the actual data). Again, the data is not unencoded.

    my $parts = $imap->get_parts_bodies(10, [ '1.1', '1.2', '2.1' ]);
    print ${$parts->{'1.1'}};

get_summaries( $msg ), get_summaries( \@msgs )

Fetches, parses and returns "message summaries". $msg can be an array ref, or a single id. The return value is an array reference (in scalar context) or a list. If a single message was passed, then in scalar context it returns only that message (not an array ref).

The result contains one or more Net::IMAP::Client::MsgSummary objects. The best way to understand the result is to actually call this function and use Data::Dumper to see its structure.

Following is the output for a pretty complicated message, which contains an HTML part with an embedded image and an attached message. The attached message in turn contains an HTML part and an embedded message.

  bless( {
    'message_id' => '<48A71D17.1000109@foobar.com>',
    'date' => 'Sat, 16 Aug 2008 21:31:51 +0300',
    'to' => [
        bless( {
            'at_domain_list' => undef,
            'name' => undef,
            'mailbox' => 'kwlookup',
            'host' => 'foobar.com'
        }, 'Net::IMAP::Client::MsgAddress' )
    ],
    'cc' => undef,
    'from' => [
        bless( {
            'at_domain_list' => undef,
            'name' => 'Mihai Bazon',
            'mailbox' => 'justme',
            'host' => 'foobar.com'
        }, 'Net::IMAP::Client::MsgAddress' )
    ],
    'flags' => [
        '\\Seen',
        'NonJunk',
        'foo_bara'
    ],
    'uid' => '11',
    'subject' => 'test with message attachment',
    'rfc822_size' => '12550',
    'in_reply_to' => undef,
    'bcc' => undef,
    'internaldate' => '16-Aug-2008 21:29:23 +0300',
    'reply_to' => [
        bless( {
            'at_domain_list' => undef,
            'name' => 'Mihai Bazon',
            'mailbox' => 'justme',
            'host' => 'foobar.com'
        }, 'Net::IMAP::Client::MsgAddress' )
    ],
    'sender' => [
        bless( {
            'at_domain_list' => undef,
            'name' => 'Mihai Bazon',
            'mailbox' => 'justme',
            'host' => 'foobar.com'
        }, 'Net::IMAP::Client::MsgAddress' )
    ],
    'parts' => [
        bless( {
            'part_id' => '1',
            'parts' => [
                bless( {
                    'parameters' => {
                        'charset' => 'UTF-8'
                    },
                    'subtype' => 'html',
                    'part_id' => '1.1',
                    'encoded_size' => '365',
                    'cid' => undef,
                    'type' => 'text',
                    'description' => undef,
                    'transfer_encoding' => '7bit'
                }, 'Net::IMAP::Client::MsgSummary' ),
                bless( {
                    'disposition' => {
                        'inline' => {
                            'filename' => 'someimage.png'
                        }
                    },
                    'language' => undef,
                    'encoded_size' => '4168',
                    'description' => undef,
                    'transfer_encoding' => 'base64',
                    'parameters' => {
                        'name' => 'someimage.png'
                    },
                    'subtype' => 'png',
                    'part_id' => '1.2',
                    'type' => 'image',
                    'cid' => '<part1.02030404.05090202@foobar.com>',
                    'md5' => undef
                }, 'Net::IMAP::Client::MsgSummary' )
            ],
            'multipart_type' => 'related'
        }, 'Net::IMAP::Client::MsgSummary' ),
        bless( {
            'message_id' => '<48A530CE.3050807@foobar.com>',
            'date' => 'Fri, 15 Aug 2008 10:31:26 +0300',
            'encoded_size' => '6283',
            'to' => [
                bless( {
                    'at_domain_list' => undef,
                    'name' => undef,
                    'mailbox' => 'kwlookup',
                    'host' => 'foobar.com'
                }, 'Net::IMAP::Client::MsgAddress' )
            ],
            'subtype' => 'rfc822',
            'cc' => undef,
            'from' => [
                bless( {
                    'at_domain_list' => undef,
                    'name' => 'Mihai Bazon',
                    'mailbox' => 'justme',
                    'host' => 'foobar.com'
                }, 'Net::IMAP::Client::MsgAddress' )
            ],
            'subject' => 'Test with images',
            'in_reply_to' => undef,
            'description' => undef,
            'transfer_encoding' => '7bit',
            'parameters' => {
                'name' => 'Attached Message'
            },
            'bcc' => undef,
            'part_id' => '2',
            'sender' => [
                bless( {
                    'at_domain_list' => undef,
                    'name' => 'Mihai Bazon',
                    'mailbox' => 'justme',
                    'host' => 'foobar.com'
                }, 'Net::IMAP::Client::MsgAddress' )
            ],
            'reply_to' => [
                bless( {
                    'at_domain_list' => undef,
                    'name' => 'Mihai Bazon',
                    'mailbox' => 'justme',
                    'host' => 'foobar.com'
                }, 'Net::IMAP::Client::MsgAddress' )
            ],
            'parts' => [
                bless( {
                    'parameters' => {
                        'charset' => 'UTF-8'
                    },
                    'subtype' => 'html',
                    'part_id' => '2.1',
                    'encoded_size' => '344',
                    'cid' => undef,
                    'type' => 'text',
                    'description' => undef,
                    'transfer_encoding' => '7bit'
                }, 'Net::IMAP::Client::MsgSummary' ),
                bless( {
                    'disposition' => {
                        'inline' => {
                            'filename' => 'logo.png'
                        }
                    },
                    'language' => undef,
                    'encoded_size' => '4578',
                    'description' => undef,
                    'transfer_encoding' => 'base64',
                    'parameters' => {
                        'name' => 'logo.png'
                    },
                    'subtype' => 'png',
                    'part_id' => '2.2',
                    'type' => 'image',
                    'cid' => '<part1.02060209.09080406@foobar.com>',
                    'md5' => undef
                }, 'Net::IMAP::Client::MsgSummary' )
            ],
            'cid' => undef,
            'type' => 'message',
            'multipart_type' => 'related'
        }, 'Net::IMAP::Client::MsgSummary' )
    ],
    'multipart_type' => 'mixed'
  }, 'Net::IMAP::Client::MsgSummary' );

As you can see, the parser retrieves all data, including from the embedded messages.

There are many other modules you can use to fetch such information. Email::Simple and Email::MIME are great. The only problem is that you have to have fetched already the full (RFC822) body of the message, which is impractical over IMAP. When you want to quickly display a folder summary, the only practical way is to issue a FETCH command and retrieve only those headers that you are interested in (instead of full body). get_summaries does exactly that (issues a FETCH (FLAGS INTERNALDATE RFC822.SIZE ENVELOPE BODYSTRUCTURE)). It's acceptably fast even for huge folders.

notifications()

The IMAP server may send various notifications upon execution of commands. They are collected in an array which is returned by this method (returns an array ref in scalar context, or a list otherwise). It clears the notifications queue so on second call it will return an empty array (unless new notifications were collected in the meantime).

Each element in this array (notification) is a hash reference containing one or more or the following:

  - seq       : the *sequence number* of the changed message
  - flags     : new flags for this message
  - deleted   : when the \Deleted flag was set for this message
  - messages  : new number of messages in this folder
  - recent    : number of recent messages in this folder
  - flags     : new flags of this folder (seq is missing)
  - destroyed : when this message was expunged
  - folder    : the name of the selected folder

folder is always present. seq is present when a message was changed some flags (in which case you have flags) or was expunged (in which case destroyed is true). When flags were changed and the \Deleted flag is present, you also get deleted true.

seq is a message sequence number. Pretty dumb, I think it's preferable to work with UID-s, but that's what the IMAP server reports. To get UID-s call seq_to_uid.

When flags is present but no seq, it means that the list of available flags for the folder has changed.

You get messages upon an "EXISTS" notification, which usually means "you have new mail". It indicates the total number of messages in the folder, not just "new" messages. I've yet to come up with a good way to measure the number of new/unseen messages, other than calling status($folder).

I rarely got recent from my IMAP server in my tests; if more clients are simultaneously logged in as the same IMAP user, only one of them will receive "RECENT" notifications; others will have to rely on "EXISTS" to tell when new messages have arrived. Therefore I can only say that "RECENT" is useless and I advise you to ignore it.

TODO

There's a bunch of missing functionality which should be quite easy to add but I didn't get to it yet. Such as create/delete folders. If you need it urgently, feel free to add it and send me a patch, otherwise wait until I need it. :-)

- authentication schemes other than plain text (help wanted)
- append/delete messages
- create/remove mailboxes
- expunge folder
- support THREAD operation
- reconnect/relogin when connection lost
- better error handling?

SEE ALSO

Net::IMAP::Simple, Mail::IMAPClient, Mail::IMAPTalk

Email::Simple, Email::MIME

RFC2060 [1] is a must read if you want to do anything fancier than what this module already supports.

REFERENCES

[1] http://ietfreport.isoc.org/rfc/rfc2060.txt

[2] http://ietfreport.isoc.org/all-ids/draft-ietf-imapext-sort-20.txt

AUTHOR

Mihai Bazon, <mihai.bazon@gmail.com> http://www.dynarchlib.com/ http://www.bazon.net/mishoo/

COPYRIGHT

Copyright (c) Mihai Bazon 2008. All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.