NAME
Net::IMAP::Server - A single-threaded multiplexing IMAP server implementation, using Net::Server::Coro.
SYNOPSIS
use Net::IMAP::Server;
Net::IMAP::Server->new(
port => 193,
ssl_port => 993,
auth_class => "Your::Auth::Class",
model_class => "Your::Model::Class",
user => "nobody",
group => "nobody",
)->run;
DESCRIPTION
This model provides a complete implementation of the RFC 3501
specification, along with several IMAP4rev1 extensions. It provides separation of the mailbox and message store from the client interaction loop.
Note that, following RFC suggestions, login is not allowed except under a either SSL or TLS. Thus, you are required to have a certs/ directory under the current working directory, containing files server-cert.pem and server-key.pem
. Failure to do so will cause the server to fail to start. Note that if the default paths suit your needs, you can specify different ones using the "server_cert" and "server_key" arguments to "new".
INTERFACE
The primary method of using this module is to supply your own model and auth classes, which inherit from Net::IMAP::Server::DefaultModel and Net::IMAP::Server::DefaultAuth. This allows you to back your messages from arbitrary data sources, or provide your own authorization backend. For the most part, the implementation of the IMAP components should be opaque.
METHODS
new PARAMHASH
Creates a new IMAP server object. This doesn't even bind to the sockets; it merely initializes the object. It will die
if it cannot find the appropriate certificate files. Valid arguments to new
include:
- port
-
The port to bind to. Defaults to port 1430.
- ssl_port
-
The port to open an SSL listener on; by default, this is disabled, and any true value enables it.
- auth_class
-
The name of the class which implements authentication. This must be a subclass of Net::IMAP::Server::DefaultAuth.
- model_class
-
The name of the class which implements the model backend. This must be a subclass of Net::IMAP::Server::DefaultModel.
- connection_class
-
On rare occasions, you may wish to subclass the connection class; this class must be a subclass of Net::IMAP::Server::Connection.
- poll_every
-
How often the current mailbox should be polled, in seconds; defaults to 0, which means it will be polled after every client command.
- unauth_commands
-
The number of commands before unauthenticated users are disconnected. The default is 10; set to zero to disable.
- unauth_idle
-
How long, in seconds, to wait before disconnecting idle connections which have not authenticated yet. The default is 5 minutes; set to zero to disable (which is not advised).
- auth_idle
-
How long, in seconds, to wait before disconnecting authenticated connections. By RFC specification, this must be longer than 30 minutes. The default is an hour; set to zero to disable.
- server_cert
-
Path to the SSL certificate that the server should use. This can be either a relative or absolute path.
- server_key
-
Path to the SSL certificate key that the server should use. This can be either a relative or absolute path.
It also accepts the following Net::Server arguments -- see its documentation for details on their use.
- "log_level" in Net::Server
- "log_file" in Net::Server
- "syslog_logsock" in Net::Server
- "syslog_ident" in Net::Server
- "syslog_logopt" in Net::Server
- "syslog_facility" in Net::Server
- "pid_file" in Net::Server
- "chroot" in Net::Server
- "user" in Net::Server
- "group" in Net::Server
- "reverse_lookups" in Net::Server
- "allow" in Net::Server
- "deny" in Net::Server
- "cidr_allow" in Net::Server
- "cidr_deny" in Net::Server
run
Starts the server; this method shouldn't be expected to return. Within this method, $Net::IMAP::Server::Server
is set to the object that this was called on; thus, all IMAP objects have a way of referring to the server -- and though "connection", whatever parts of the IMAP internals they need.
Any arguments are passed through to "run" in Net::Server.
process_request
Accepts a client connection; this method is needed for the Net::Server infrastructure.
DESTROY
On destruction, ensure that we close all client connections and listening sockets.
connections
Returns an arrayref of Net::IMAP::Server::Connection objects which are currently connected to the server.
connection
Returns the currently active Net::IMAP::Server::Connection object, if there is one. This is determined by examining the current coroutine.
concurrent_mailbox_connections [MAILBOX]
This can be called as either a class method or an instance method; it returns the set of connections which are concurrently connected to the given mailbox object (which defaults to the current connection's selected mailbox)
concurrent_user_connections [USER]
This can be called as either a class method or an instance method; it returns the set of connections whose "user" in Net::IMAP::Server::DefaultAuth is the same as the given USER (which defaults to the current connection's user)
capability
Returns the CAPABILITY
string for the server. This string my be modified by the connection before being sent to the client (see "capability" in Net::IMAP::Server::Connection).
id
Returns a hash of properties to be conveyed to the client, should they ask the server's identity.
add_command NAME => PACKAGE
Adds the given command NAME
to the server's list of known commands. PACKAGE
should be the name of a class which inherits from Net::IMAP::Server::Command.
log SEVERITY, MESSAGE
By default, defers to "log" in Net::Server, which outputs to syslog, a logfile, or STDERR, depending how it was configured. Net::Server's default is to print to STDERR. If you have custom logging needs, override this method, or "write_to_log_hook" in Net::Server.
Object model
An ASCII model of the relationship between objects is below. In it, single lines represent scalar values, and lines made of other characters denote array references or relations.
+----------------------------------------------+
| |
| Server |
| |
+1-----2---------------------------------------+
# | ^ ^ ^ ^
# | | | | |
# v | | | |
# +--------1-------+ | +------1------+ |
###>| Connection |<------2 Command | |
# +--4-----3------2+ | +-------------+ |
,-#------' | `--------------. |
| # v | v |
| # +----------------+ | +-------------+ |
| # | Model 2------>| Auth | |
| # +--------1-------+ | +-------------+ |
| # `---------------------------------.
| # | | |
| # ,---' ,---' |
| # +--------------1-+ +-----------1-+ |
| ###>| Connection |<------2 Command | |
| +--4-5---3------2+ +-------------+ |
| ,------' * | `--------------. |
| | ******** v v |
| | * +----------------+ +-------------+ |
| | * | Model 2------>| Auth | |
| | * +--------1-------+ +-------------+ |
| | * | |
| | * | ,------------------------------'
| | * | | ^ SERVER
.|.|.*..........|..|................................
| | * | | v MODEL
| | * v v
| '-*---->+-------------+<------------.
'---*---->| Mailbox |<----------. |
* +-1------2-3--+<----. | |
* @ ^ $ % | | |
* @ | $$$$>+-----1---+ | |
* @ | $ % | | | |
* @ | $ %%>| Message | | |
* @ | $ % | | | |
********@***|******>+---------+ | |
* @ | $ % | |
* @ | $$$$>+---------+ | |
* @ | % | | | |
* @ | %%>| Message 1-' |
* @ | | | |
********@***|******>+---------+ |
* @ | |
* @ | +---------+ |
* @ | | Message 1---'
********@***|******>+---------+
@ |
@ +4----------+
@@>| Mailbox |
+-----------+
The top half consists of the parts which implement the IMAP protocol itself; the bottom contains the models for the backing store. Note that, for the most part, the backing store is unaware of the framework of the server itself.
Each model has references to others, as follows:
- Server
-
Contains references to the set of
connections
(1). It also has a sense of the currentconnection
(2), based on the active Coro thread. - Connection
-
Connections hold a reference to their
server
(1). If the connection has authenticated, they hold a reference to theauth
object (2), and to theirmodel
(3). If a mailbox isselected
(4), they hold a pointer to that, as well. Infrequently, the connection will need to temporarily store references to the set oftemporary_messages
(5) which have been expunged in other connections, but we have been unable to notify this connection of. - Command
-
Commands store their
server
(1) andconnection
(2). - Model
-
Models store a reference to the
root
(1) of their mailbox tree, as well as to theauth
(2) which gives them access to such. - Mailbox
-
Mailboxes store a list of
children
mailboxes (1), andmessages
(2) contained within them, which are stored in sequence order. They also contain a hash ofuids
(3) for fast UID retrieval of messages. If they are not the root mailbox, they also store a reference to theirparent
mailbox (4). - Message
-
Messages store the
mailbox
(1) in which they are contained.
DEPENDENCIES
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests to bug-net-imap-server@rt.cpan.org
, or through the web interface at http://rt.cpan.org.
A low-traffic mailing list exists for discussion on how to (ab)use this module, at http://lists.bestpractical.com/cgi-bin/mailman/listinfo/net-imap-server.
AUTHOR
Alex Vandiver <alexmv@bestpractical.com>
LICENCE AND COPYRIGHT
Copyright (c) 2010, Best Practical Solutions, LLC. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.
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