ePowerSwitch.pm Perl Module

SYNOPSIS

    use ePowerSwitch;

    $eps = ePowerSwitch->new($ip_address, $port,
                             $password, $socket);
    $eps->login();
    $eps->logout();
    $are_we = $eps->loggedin();
    $ok = $eps->switch($socket_number, $command);
    $eps->describe($filehandle);
    $swname = $eps->switchname();
    $sockname = $eps->socketname($socket_number);
    $on_or_off = $eps->socketstat($socket_number);
    $vmode = $eps->verbose($mode);

DESCRIPTION

The ePowerSwitch is a TCP/IP compatible power strip with four outlets which can be controlled via HTTP requests to an embedded mini Web server. For details about the ePowerSwitch, see the manufacturer's site:

http://www.neol.com/

This module provides an object-oriented interface to an ePowerStrip. A program can create one or more ePowerSwitch objects, each bound to a specific network-accessible switch (or an individual socket on a switch), and then query status and switch power on and off with method calls.

METHODS

$eps = ePowerSwitch->new($ip_address, $port, $password, $socket);

The new method is the constructor for the ePowerSwitch class. It creates a new ePowerSwitch with IP address $ip_address and port $port. You can create an ePowerSwitch object to access all outlets on the switch by specifying the administration password for $password and 0 for $socket (or omitting the $socket argument), or to access a single socket by supplying the “user” password for that socket and its socket number (1 through 4) as $socket. The constructor returns a new ePowerSwitch object which may be manipulated through the following methods.

$eps->login();

Logs in to to the power switch (either for administrative access to all sockets or a specific socket, depending on the $password and $socket given when the object was created with new). You must log in before using any methods which query the status of the switch or turn sockets on or off. Returns 1 if the login was successful, 0 if the login failed.

$eps->logout();

Logs out from the power switch. Returns 1 if the logout was successful, 0 if it fails. You can log in and out as many times as you wish.

$are_we = $eps->loggedin();

Returns 1 if currently logged in to the switch, 0 if not logged in.

$ok = $eps->switch($socket_number, $command);

Sends a command, specified by a single character $command argument, to socket $socket_number. If you created the ePowerSwitch with the administrative password, $socket_number can be any socket (1 through 4). If you gave the password for a single socket in the call to new, the $socket_number must be the same as the $socket specified in the new call.

Commands are as follows:

'0'

Turn socket off.

'1'

Turn socket on.

't'

Toggle: if socket is off, turn it on; if on, turn it off.

'r'

Reboot: turn socket off, wait 60 seconds, then turn the socket back on. After a reboot command is given, the switch method returns immediately—it does not wait until the socket is turned back on.

The switch method returns 1 if the command was executed normally and 0 if an error occurred.

$eps->describe($filehandle);

The properties and status of the ePowerSwitch are printed on the file opened on $filehandle or, if $filehandle is omitted, STDOUT. (If you want to print the status on a filehandle OFILE, pass a reference to it: describe(\*OFILE).) The arguments used to create the object with new are shown, then the login status. If logged in to the switch, its name, and the name and on/off status of each of the sockets is shown if logged in with the administrative password. If logged in with the password for a single socket, only the status of that socket is shown.

swname = $eps->switchname();

Returns a string containing the name of the ePowerSwitch. You must be logged in to retrieve the switch name; either the administrative password or the password for a single socket entitles you to query the name of the switch.

$sockname = $eps->socketname($socket_number);

Returns the name of the socket specified by $socket_number (1 through 4). You must be logged in; if logged in with the administrative password, you may obtain the name of any socket. If logged in with the password for a single socket, only the name of that socket may be retrieved.

$on_or_off = $eps->socketstat($socket_number);

Returns 1 if the specified $socket_number is on, 0 if it is off. You must be logged in to query the socket status. If logged in with the administrative password, you can query the status of any socket (1 through 4); if logged in with the password for a specific socket, only that socket's status may be obtained.

$vmode = $eps->verbose($mode);

By default, errors in communicating with the switch simply return a zero status to the caller. (Invalid arguments, however, use die to report the error.) If you set verbose mode by calling verbose with a nonzero $mode argument, diagnostic messages will be printed on standard output for all operations, successful or not. The previous setting of verbose mode is returned, permitting you to save and restore it

VERSION

This is ePowerSwitch version 1.0, released on November 8th, 2003.

AUTHOR

    John Walker
    http://www.fourmilab.ch/

BUGS

This module requires the LWP (“Library for the World Wide Web in Perl”) module; if it isn't installed on your system, you can obtain the current version from CPAN.

The term “socket” is used herein exclusively to refer to the outlets on the power strip into which you plug stuff, not network sockets, notwithstanding that the latter are used in the process of controlling the former.

Please report any bugs to bugs at fourmilab.ch

SEE ALSO

ePowerSwitch command line utility.

COPYRIGHT

This program is in the public domain.