NAME
    POE::Component::Client::SimpleFTP - A simple FTP client library for POE

VERSION
      This document describes v0.003 of POE::Component::Client::SimpleFTP - released May 04, 2011 as part of POE-Component-Client-SimpleFTP.

SYNOPSIS
            # A simple FTP client logging in to a server
            use POE qw( Component::Client::SimpleFTP );

            POE::Session->create(
                    inline_states => {
                            _start => sub {
                                    POE::Component::Client::SimpleFTP->new(
                                            alias => "ftp",
                                            remote_addr => "invalid.addr",
                                            username => "myuser",
                                            password => "mypassword",
                                    );
                                    return;
                            },
                            authenticated => sub {
                                    print "LOGGED ON!\n";
                                    $_[KERNEL]->post( "ftp", "quit" );
                                    return;
                            }
                    },
            );
            POE::Kernel->run;

DESCRIPTION
    This is a simple FTP client to use in a POE application. It's a complete
    rewrite of the old POE::Component::Client::FTP codebase and makes it
    easier to use. Most of the API/event flow is compatible, so you should
    have few problems porting your code to this module.

    You start by creating the ftp object and wait for it to send you events.
    By default the caller session will get all the events directed to it, no
    need to "register" for events or anything like that. Events are sent to
    you in the generic form of $command or "${command}_error" events. This
    module will parse the FTP reply codes and determine if it is an error or
    not, and dispatch it to the appropriate event.

    An important thing to keep in mind is that there is no command queueing
    done in this module. It is up to the user to know what state they are in
    and to dispatch events at the right time. If a command is sent while
    this module is processing one, an exception will be thrown. Fortunately,
    due to the way events are named, it should be easy to keep track of the
    event flow.

  Initial Connection
    When the object is created, it attempts to make a connection to the
    server specified in the attributes. It will automatically login with the
    provided credentials. Additionally, it will enable TLS mode if you
    enabled the attributes "tls_cmd" and "tls_data". There is a timeout
    timer on the initial connection that you can tweak via setting
    "timeout".

    The following events may be sent to your session:

   authenticated
    This event is sent when the entire login procedure is done. At this
    point you can send commands to the server.

    No arguments.

   connect_error
    This event is sent when there's an error connecting to the server. The
    component will automatically destroy itself at this point, so if you
    want to retry the connection, you have to make a new object.

    The first argument is the error code, and the 2nd argument is the error
    string.

    The code "0" is used here, because we never got a reply from the server.
    However, it is nice to have consistency with the other event handlers,
    so it is supplied.

    Example code: 0

    Example reply: timedout

   login_error
    This event is sent when there's an error trying to login to the server.
    The component will automatically destroy itself at this point, so if you
    want to retry the connection, you have to make a new object.

    The first argument is the error code, and the 2nd argument is the error
    string.

    Example code: 530

    Example reply: Login incorrect.

  Simple Commands
    This is a class of commands that can be sent to the server after
    receiving the "authenticated" event. They perform identically, and will
    send the same replies back to your session. Some commands require
    arguments, others don't.

    Normally the events will include at least 2 arguments: the FTP return
    code and the actual reply line from the server. If the command included
    arguments, it will be supplied in the event to make identifying actions
    easier.

    Some commands is an alias for the actual command ( cd vs cwd ) but the
    event name will follow the aliased command. If a cwd event is sent, the
    error event is "cwd_error". If a cd event is sent, the error event is
    "cd_error".

            # send the cd command in an event handler somewhere
            $ftp->yield( 'cd', '/foobar' );

            # handler for the resulting event received from this component
            sub cd {
                    my( $code, $reply, $path ) = @_[ ARG0 .. ARG2 ];

                    # $code probably is 250
                    # $reply probably is "Directory successfully changed."
                    # $path will be "/foobar"
            }

            sub cd_error {
                    my( $code, $reply, $path ) = @_[ ARG0 .. ARG2 ];

                    # $code probably is 550
                    # $reply probably is "Failed to change directory."
                    # $path will be "/foobar"
            }

   cwd
    Changes the working directory.

    Arguments: the path to change to ( required )

    Example code: 250

    Example reply: Directory successfully changed.

   cd
    An alias for "cwd"

   dele
    Deletes a file.

    Arguments: the file to delete ( required )

    Example code: 250

    Example reply: Delete operation successful.

   delete
    An alias for "dele"

   mkd
    Creates a directory.

    Arguments: the directory path to create ( required )

    You can supply an absolute path or a relative path. It is up to the
    server to figure out where to create the directory. It's easier to use
    absolute paths so you are sure that the server is creating the directory
    in the right place!

    Remember, the FTP protocol doesn't support recursive directory creation!
    If "/foo" exists but "/foo/bar" doesn't, then you cannot create
    "/foo/bar/baz"!

    Example code: 257

    Example reply: "/foo" created

   mkdir
    An alias for "mkd"

   rmd
    Removes a directory.

    Arguments: the directory path to delete ( required )

    You can supply an absolute path or a relative path. It is up to the
    server to figure out where to delete the directory. It's easier to use
    absolute paths so you are sure that the server is deleting the right
    directory!

    Example code: 250

    Example reply: Remove directory operation successful.

   rmdir
    An alias for "rmd"

   cdup
    Changes the working directory to the parent.

    Remember, there might be symlinks or other bizarre stuff going on behind
    the scenes! It's best to supply full pathnames to "cwd" to be safe.

    Arguments: none

    Example code: 250

    Example reply: Directory successfully changed.

   pwd
    Prints the current working directory.

    Arguments: none

    Example code: 257

    Example reply: "/"

   rename
    Renames a target file to a new name.

    Arguments: the old filename and the new filename

    Remember, the pathnames must exist and is a valid target. Best to send
    absolute paths!

    Example code: 250

    Example reply: Rename successful.

   mv
    An alias for "rename"

   quit
    Disconnects from the server. Behaves differently depending on the
    context when this command is received. After this command is sent, this
    module will destroy itself and not send any more events to your session.

    If this module isn't processing anything it will send the QUIT command
    and gracefully shutdown when it receives the server reply.

    If this module is processing a command it will disconnect immediately,
    killing any command processing/data transfers that is happening.

    If you want to force immediate shutdown, use the "shutdown" event.

    Arguments: none

   disconnect
    An alias for "quit"

   shutdown
    Forces a shutdown of the component and kills everything.

    Arguments: none

   noop
    Executes a no-operation command. Useful to keep the connection open or
    to get the round-trip latency, or whatever :)

    Arguments: none

    Example code: 200

    Example reply: NOOP ok.

   quot
    Sends a quoted command to the server. Useful for sending commands that
    this module doesn't support.

    Arguments: the actual command + arguments to send.

            $ftp->yield( 'quot', 'CRAZYCMD', @crazy_args );

   quote
    An alias for "quot"

   help
    Gets the server's help output for a command.

    Arguments: optional command to ask for help

    Example code: 214

    Example reply:

            The following commands are recognized.
            ABOR ACCT ALLO APPE CDUP CWD  DELE EPRT EPSV FEAT HELP LIST MDTM MKD
            MODE NLST NOOP OPTS PASS PASV PORT PWD  QUIT REIN REST RETR RMD  RNFR
            RNTO SITE SIZE SMNT STAT STOR STOU STRU SYST TYPE USER XCUP XCWD XMKD
            XPWD XRMD
            Help OK.

   site
    Executes a specific command that the server supports. Consult your ftp
    administrator or the document for the ftpd software for more
    information.

    Arguments: the command to execute + any optional arguments.

    Example code: 500

    Example reply: Unknown SITE command.

   stat
    Receives some informational text about the current status of the
    connection.

    BEWARE: While the RFC says this command can be sent while a data
    transfer is in progress, this is unimplemented!

    Arguments: none

    Example code: 211

    Example reply:

            FTP server status:
            Connected to 192.168.0.199
            Logged in as apoc
            TYPE: ASCII
            No session bandwidth limit
            Session timeout in seconds is 300
            Control connection is plain text
            Data connections will be plain text
            At session startup, client count was 1
            vsFTPd 2.2.0 - secure, fast, stable
            End of status

   syst
    Gets the system information of the server.

    Arguments: none

    Example code: 215

    Example reply: UNIX Type: L8

   acct
    Send the account information for your login. Generally not used, but if
    your server requires it you should send this immediately after getting
    the "authenticated" event.

    Arguments: your account information

    Example code: 502

    Example reply: ACCT not implemented.

   smnt
    Mounts a different filesystem volume on your account. Generally not
    used.

    Arguments: a pathname to mount or system-specific string

    Example code: 502

    Example reply: SMNT not implemented.

   mdtm
    Gets the modification time of a file. Not supported by all servers! (
    RFC 3659 )

    Arguments: the file to query

    Example code: 213

    Example reply: 20110502230157

    You can use the "mdtm_parser" in
    POE::Component::Client::SimpleFTP::Utils function to convert it into a
    DateTime object.

   size
    Gets the size of a file in bytes. Not supported by all servers! ( RFC
    3659 )

    Arguments: the file to query

    Example code: 213

    Example reply: 48

   feat
    Queries the FEAT capabilities of the server. Not supported by all
    servers! ( RFC 2389 )

    Arguments: none

    Example code: 211

    Example reply:

            Features:
            EPRT
            EPSV
            MDTM
            PASV
            REST STREAM
            SIZE
            TVFS
            UTF8
            End

    You can use the "feat_parser" in
    POE::Component::Client::SimpleFTP::Utils function to convert it into an
    array of features.

   features
    An alias for "feat"

   opts
    Sets an option for the current session. Not supported by all servers! (
    RFC 2389 )

    Arguments: the option to set

    Example code: 501

    Example reply: Option not understood.

   options
    An alias for "opts"

  Complex Commands
    This class of commands is called complex because they require opening a
    new data connection to the server. The requested data is transferred
    over this connection, and the result is sent back to your session. All
    of the commands behave the same except for the "upload" types.

    Please look at the "examples" directory included in this distribution
    for code samples.

    The typical flow of this command is as follows:

            $ftp->yield( 'get', "/myfile.txt" );

            # receive a "get_connected" event
            #       args is: "/myfile.txt"

            # at this point you prepare to process the incoming data

            # receive a "get_data" event
            #       args is: $chunk, "/myfile.txt"

            # at this point you should write out the data to the terminal, a file, or whatever!

            # ... keep receiving "get_data" until the server finish sending

            # receive a "get" event
            #       args is: $code, $reply, "/myfile.txt"

            # at this point the transfer is complete

            # if at any point there is an error, a "get_error" event is sent
            #       args is: $code, $reply, "/myfile.txt"

    For the "upload" events where you are sending data to the server, the
    flow is:

            $ftp->yield( 'put', '/myfile.txt' );

            # receive a "put_connected" event
            #       args is: "/myfile"

            # at this point you should get the data to send to the server
            # from your local filesystem, from a database server, or whatever!

            # send a chunk of data to the server
            # the chunk size should depend on your application - a reasonable default is 10240 bytes
            $ftp->yield( 'put_data', $chunk );

            # receive a "put_flushed" event
            #       args is: "/myfile"

            # at this point, you can either send another chunk or signal EOF
            $ftp->yield( 'put_close' );

            # receive a "put" event
            #       args is: $code, $reply, "/myfile"

            # at this point the transfer is complete

            # if at any point there is an error, a "put_error" event is sent
            #       args is: $code, $reply, "/myfile"

   list
    Receives a directory list. The data is sent in a format similar to the
    UNIX "ls" command, but can be anything!

    Arguments: the optional path to query ( defaults to current working
    directory )

    Example data:

            drwxr-xr-x    4 1000     1000         4096 May 02 18:24 a
            drwxr-xr-x    4 1000     1000         4096 May 02 18:24 b
            drwxr-xr-x    4 1000     1000         4096 May 02 18:24 c
            -rw-r--r--    1 1000     1000            0 May 02 20:26 foo.txt

   ls
    An alias for list

   nlst
    Receives a directory list. Differs from list in that only the names are
    received.

    Arguments: the optional path to query ( defaults to current working
    directory )

    Example data:

            a
            b
            c
            foo.txt

   dir
    An alias for "nlst"

   retr
    Retrieves a file from the server.

    Arguments: the filename to receive

   get
    An alias for "get"

   stor
    Transmits a file to the server. This uses the "upload" command flow
    explained in "Complex Commands"!

    Arguments: the filename to put

   stou
    Transmits a file to the server. This differs from "stor" in that the ftp
    server is required to store the file in a unique way. This uses the
    "upload" command flow explained in "Complex Commands"!

    Arguments: the filename to put

   put
    An alias for "stor"

ATTRIBUTES
  alias
    The alias this component will use. You can send commands to the ftpd in
    2 ways:

            my $ftp = POE::Component::Client::SimpleFTP->new( alias => "ftp", ... );
            $poe_kernel->post( 'ftp', 'cd', 'foobar' );

            # Or, you can use the yield sub:
            $ftp->yield( 'cd', 'foobar' );

    The default is: ftp

  username
    The FTP username you will be sending to the server.

    required.

  password
    The FTP password you will be sending to the server.

    required.

  remote_addr
    The IP address of the FTP server to connect to. Can be a DNS hostname or
    IPv4/6 string.

    required.

  remote_port
    The port of the FTP server to connect to.

    The default is: 21

  local_addr
    The local IP address to bind to for all connections to the server.

    The default is: INADDR_ANY ( let the OS decide )

  local_port
    The local port to bind to for the control connection to the server. If
    you need to change the data connection's port, please change the
    "local_data_port" attribute.

    The default is: 0 ( let the OS decide )

  local_data_port
    The local port to bind to for the data connection to the server. Must be
    a different port than the "local_port" attribute!

    The default is: 0 ( let the OS decide )

  tls_cmd
    A boolean value to enable/disable TLS encryption of the command
    connection. If you want to use this, you must have
    POE::Component::SSLify installed!

    The default is: false

  tls_data
    A boolean value to enable/disable TLS encryption of the data connection.
    If you want to use this, you must have POE::Component::SSLify installed!

    The default is: false

  timeout
    A value specifying the timeout in seconds for the initial connection to
    the FTP server.

    The default is: 120

  connection_mode
    Determine what connection mode we will be using when opening the data
    connection to the server. In "active" mode, the server will be
    connecting to us. In "passive" mode we will be connecting to the server.
    You usually need "passive" mode if you are behind a firewall.

    The default is: passive

FUNCTIONS
  DEBUG
    Enable this if you want to get debugging output. Do it like this:

            sub POE::Component::Client::SimpleFTP::DEBUG () { 1 }
            use POE::Component::Client::SimpleFTP;

    The default is: false

  yield
    This method provides an alternative object based means of posting events
    to the component. First argument is the event to post, following
    arguments are sent as arguments to the resultant post.

            my $ftp = POE::Component::Client::SimpleFTP->new( ... );
            $ftp->yield( 'cd', 'foobar' );

            # equivalent to:
            $poe_kernel->post( $ftp->alias, 'cd', 'foobar' );

TLS support
    TLS encryption is available if you want. You would need to enable the
    "tls_cmd" and "tls_data" attributes and have POE::Component::SSLify
    installed in order to use it. It should work with a lot of servers and
    commands. However, not the entire specification is implemented! If you
    encounter problems when using TLS on a server, please let me know by
    filing a bug report!

Unimplemented Commands/Actions/Features
    Those are the ideas that probably will be implemented in a future
    version. Some of them require core changes to this module, while others
    can be done in user-space but should be implemented here to make it
    "simpler" :)

            * full TLS support - check the RFCs
            * FXP ( server<->server ) transfers
            * intelligent NAT detection
            * full ipv6 compatibility
            * restart/abort/append a transfer
            * bandwidth throttling for data connection
            * support for "mkdir -p" where this module automatically creates all directories needed
            * passing a filename/filehandle/whatever to put/get so this module automatically does the reading/writing
            * directory mirroring ( ala rsync )
            * use POE::Filter::Ls for parsing ( need to improve it first hah )
            * encoded pathnames ( translate \012 in filename to \000 as per RFC 959 )
            * security stuff - http://cr.yp.to/ftp/security.html
            * event prefix ( so you get ftp_cd events instead of cd ) for easier event management
            * strict command validation ( we don't check if the command requires 0, 1, or N args )

  RFC 959 "FILE TRANSFER PROTOCOL (FTP)"
            * REIN ( not allowed, as it generally screws up - just reconnect! )
            * STRU ( default file type is always a good idea )
            * MODE ( default stream type is always a good idea )
            * APPE ( should be easy to implement, but im lazy )
            * ALLO ( it is generally unused and obsolete? )
            * REST ( a bit tricky to implement, maybe later )
            * ABOR ( not allowed, as it generally screws up - just disconnect! )
            * PASV ( this module automatically does it )
            * PORT ( this module automatically does it )
            * TYPE ( this module automatically does it )
            * STAT ( implemented, but not allowed while a transfer is in progress as it generally screws things up )

  RFC 2228 "FTP Security Extensions"
            * AUTH ( only AUTH TLS is supported now )
            * PROT/PBSZ is supported with the default options if you enable tls_cmd/tls_data
            * ADAT ( not needed for AUTH TLS? )
            * CCC ( not needed with TLS? )
            * MIC ( not needed with TLS? )
            * CONF ( not needed with TLS? )
            * ENC ( not needed with TLS? )

  RFC 2389 "Feature negotiation mechanism for the File Transfer Protocol"
            * The entire RFC is implemented

  RFC 2428 "FTP Extensions for IPv6 and NATs"
            * EPRT
            * EPSV

  RFC 2577 "FTP Security Considerations"
            * unimplemented

  RFC 2640 "Internationalization of the File Transfer Protocol"
            * unimplemented

  RFC 3659 "Extensions to FTP"
            * REST ( same reason as the RFC 959 one )
            * MLST
            * MLSD

  RFC 4217 "Securing FTP with TLS"
            * unimplemented except for what is implemented in 2228 :)

  RFC 5796 "FTP Command and Extension Registry"
            * No need to implement this, it is for servers only

SUPPORT
  Perldoc
    You can find documentation for this module with the perldoc command.

      perldoc POE::Component::Client::SimpleFTP

  Websites
    The following websites have more information about this module, and may
    be of help to you. As always, in addition to those websites please use
    your favorite search engine to discover more resources.

    *   Search CPAN

        The default CPAN search engine, useful to view POD in HTML format.

        <http://search.cpan.org/dist/POE-Component-Client-SimpleFTP>

    *   RT: CPAN's Bug Tracker

        The RT ( Request Tracker ) website is the default bug/issue tracking
        system for CPAN.

        <http://rt.cpan.org/NoAuth/Bugs.html?Dist=POE-Component-Client-Simpl
        eFTP>

    *   AnnoCPAN

        The AnnoCPAN is a website that allows community annonations of Perl
        module documentation.

        <http://annocpan.org/dist/POE-Component-Client-SimpleFTP>

    *   CPAN Ratings

        The CPAN Ratings is a website that allows community ratings and
        reviews of Perl modules.

        <http://cpanratings.perl.org/d/POE-Component-Client-SimpleFTP>

    *   CPAN Forum

        The CPAN Forum is a web forum for discussing Perl modules.

        <http://cpanforum.com/dist/POE-Component-Client-SimpleFTP>

    *   CPANTS

        The CPANTS is a website that analyzes the Kwalitee ( code metrics )
        of a distribution.

        <http://cpants.perl.org/dist/overview/POE-Component-Client-SimpleFTP
        >

    *   CPAN Testers

        The CPAN Testers is a network of smokers who run automated tests on
        uploaded CPAN distributions.

        <http://www.cpantesters.org/distro/P/POE-Component-Client-SimpleFTP>

    *   CPAN Testers Matrix

        The CPAN Testers Matrix is a website that provides a visual way to
        determine what Perls/platforms PASSed for a distribution.

        <http://matrix.cpantesters.org/?dist=POE-Component-Client-SimpleFTP>

    *   CPAN Testers Dependencies

        The CPAN Testers Dependencies is a website that shows a chart of the
        test results of all dependencies for a distribution.

        <http://deps.cpantesters.org/?module=POE::Component::Client::SimpleF
        TP>

  Email
    You can email the author of this module at "APOCAL at cpan.org" asking
    for help with any problems you have.

  Internet Relay Chat
    You can get live help by using IRC ( Internet Relay Chat ). If you don't
    know what IRC is, please read this excellent guide:
    <http://en.wikipedia.org/wiki/Internet_Relay_Chat>. Please be courteous
    and patient when talking to us, as we might be busy or sleeping! You can
    join those networks/channels and get help:

    *   irc.perl.org

        You can connect to the server at 'irc.perl.org' and join this
        channel: #perl-help then talk to this person for help: Apocalypse.

    *   irc.freenode.net

        You can connect to the server at 'irc.freenode.net' and join this
        channel: #perl then talk to this person for help: Apocal.

    *   irc.efnet.org

        You can connect to the server at 'irc.efnet.org' and join this
        channel: #perl then talk to this person for help: Ap0cal.

  Bugs / Feature Requests
    Please report any bugs or feature requests by email to
    "bug-poe-component-client-simpleftp at rt.cpan.org", or through the web
    interface at
    <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=POE-Component-Client-Sim
    pleFTP>. You will be automatically notified of any progress on the
    request by the system.

  Source Code
    The code is open to the world, and available for you to hack on. Please
    feel free to browse it and play with it, or whatever. If you want to
    contribute patches, please send me a diff or prod me to pull from your
    repository :)

    <http://github.com/apocalypse/perl-poe-component-simpleftp>

      git clone git://github.com/apocalypse/perl-poe-component-simpleftp.git

AUTHOR
    Apocalypse <APOCAL@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2011 by Apocalypse.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.

    The full text of the license can be found in the LICENSE file included
    with this distribution.

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.

