Brad McConahay

NAME

Ham::APRS::LastPacket - A simple interface to retrieve the most recent packet data for a station from APRS-IS.

VERSION

Version 0.02

SYNOPSIS

 use Ham::APRS::LastPacket;

 my $aprs = Ham::APRS::LastPacket->new; 
 $aprs->set_callsign('n8qq');
 my $packet = $aprs->get_data;

 die $aprs->error_message if $aprs->is_error;

 # show the entire structure of data
 use Data::Dumper;
 print Dumper($packet);

 # get a single item
 print $aprs->get_callsign;
 print " is at $packet->{position}->{longitude}->{degrees} degrees longitude.\n";

DESCRIPTION

The Ham::APRS::LastPacket module retrieves the latest packet from APRS-IS for a given station's callsign by referencing the aprsworld-to-XML interface. You provide the callsign for a station that exists in APRSWorld, and you will get back a hashref of hashrefs containing all data available for that station's latest packet. Use Data::Dumper to inspect the data to see all items that are available (as shown in the synopsis). The data set returned can differ based on what type of station is being referenced. For instance, a weather station will contain weather data that another type of station won't.

CONSTRUCTOR

new()

 Usage    : my $aprs = Ham::APRS::LastPacket->new;
 Function : creates a new Ham::APRS::LastPacket object
 Returns  : a Ham::APRS::LastPacket object
 Args     : a hash:
            key             required?   value
            -------         ---------   -----
            timeout         no          an integer of seconds to wait for
                                        the timeout of the web site
                                        default = 10
            suppress_empty  no          set the handling for empty elements
                                        suppress_empty => 1 will exclude empty elements
                                        suppress_empty => '' will set them to an empty hash
                                        suppress_empty => undef will set the hashes to undef
                                        default is empty string

METHODS

set_callsign()

 Usage    : $aprs->set_callsign( $callsign );
 Function : set the callsign of the station whose data will be retrieved with get_data()
 Returns  : n/a
 Args     : a case-insensitive string containing the callsign of the station in APRS-IS.
            you can use CWOP callsigns and callsigns with SSIDs.

get_callsign()

 Usage    : $callsign = $aprs->get_callsign;
 Function : get the callsign that was set with the most recent call to set_callsign().
 Returns  : a string.  (the callsign will have been converted to upper case)
 Args     : n/a

get_data()

 Usage    : $data = $aprs->get_data;
 Function : get a hashref of hashrefs of the data contained in APRS-IS for the station set in set_callsign()
 Returns  : a hashref of hashrefs
 Args     : n/a

is_error()

 Usage    : if ( $aprs->is_error )
 Function : test for an error if one was returned from the call to the aprsworld-to-XML site
 Returns  : a true value if there has been an error
 Args     : n/a

error_message()

 Usage    : my $err_msg = $aprs->error_message;
 Function : if there was an error message when trying to call the site, this is it
 Returns  : a string (the error message)
 Args     : n/a

DEPENDENCIES

TODO

  • Maybe provide a list of data items and the hashref hierarchy.

  • Improve the module description.

  • Improve error checking.

ACKNOWLEDGEMENTS

  • This module gets its data from the aprsworld-to-XML interface, by Brad McConahay N8QQ (me). See http://aprsearch.net/xml

  • The aprsworld-to-XML interface gets its data from APRSWorld, by Jim Jarvis KB0THN. See http://aprsworld.net

  • APRS-IS is the Internet-based network which inter-connects various APRS radio networks throughout the world (and space). See http://aprs-is.net

  • APRS was created by, and is a trademark of, Bob Bruninga WB4APR. See http://aprs.org

AUTHOR

Brad McConahay N8QQ, <brad at n8qq.com>

COPYRIGHT AND LICENSE

Copyright 2008 Brad McConahay N8QQ, all rights reserved.

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