Perl Script for Downloading GOES Data

#!/usr/bin/perl
#
# RETRIEVE_GOES_BUFFER:  Downloads binary data file from Wallops.
#
#  original author: J. Doutt
#  date: 5 June 2001
#  rev:  010718.1020
#  Modified by John Evans, 2 February 2002
#
#
#  This file contains the subroutines needed for the "gomoos" processing
#
#  getdata       PERL "expect" script for getting the GEOS data & saving
#                   into a file
#
# USAGE:  > retrieve_goes_buffer.pl platform_id binary_file
#
# PARAMETERS:
#    platform_id:
#        This is an 8 character alphanumeric id that is unique for each
#        buoy that transmits thru goes.  For example, the platform id 
#        for A0103 is "0440465E"
#    binary_file:
#        each message (data payload from Wallops) is saved to this file.
#        The file is not decoded here.



use Expect;

	$num_args = @ARGV;
	if ( $num_args != 2 ) {
		printf ( STDERR "Expecting 2 input arguments, got %d instead.\n", $num_args );
		exit -1;
	}

	$platform_id = $ARGV[0];
	$output_file = $ARGV[1];

	printf ( STDOUT "platform id is set to %s\n\n", $platform_id );

	printf ( STDOUT "calling getdata...\n\n" );
	&getdata ( "128.154.62.173", "usgs01", "wallopscda", "uomdoa", "aaaaaa", $platform_id, $output_file );


	exit 0;




########## getdata ######################################################
#
sub getdata  {
#
#  auth: J. Doutt
#  date: 31 May 2001
#  rev:  0106011.1400
#  
#  retrievs data GOES data from DCS.NOAA.GOV
#  automatically creates date-related file containing the data
#  deletes that file if there is no data in it
#
#  returns the timestamp part of the file name if successful, -1 if unsuccessful

	use strict;


	my($hostname,$NAME1,$PSWD1,$NAME2,$PSWD2,$PLATFORM1,$OUTPUTFILE);
	($hostname,$NAME1,$PSWD1,$NAME2,$PSWD2,$PLATFORM1,$OUTPUTFILE)=@_;

	my($telnet);
	my($logtime,$logfile,$timeout);
	my($do_message_file);

	$timeout=120;


	#
	#  Select whether we want to download a message file or a platform ID
	#  0 for getting data from platform ID
	#  list id number for getting data from a message file
	#  $do_message_file = 1;  #  >=1 to download a message file   (e.g. list_id 1)
	#  $do_message_file = 2;  #  >=1 to download a message file   (e.g. list_id 1)
	$do_message_file = 0;  #   =0 to download a platform ID    (e.g. 3130646)




	# Set up file name for logging the data
	#
	my($sec,$min,$hour,$mday,$mon,$year,@tmp);      # for getting the time
	($sec,$min,$hour,$mday,$mon,$year,@tmp)=localtime(time);

	$logtime = sprintf("%4d%02d%02d.%02d%02d",$year+1900,$mon+1,$mday,$hour,$min);
	$logfile = $OUTPUTFILE;
	printf ( STDOUT "log file set to $logfile...\n\n" );
	print "$logfile\n";



	#
	# Wallops CDA FireWall
	# spawn telnet 128.154.62.173
	($telnet = Expect->spawn("telnet $hostname"))  || die"Couldn't spawn telnet, $!";
	#           expect     "User:"
	unless ($telnet->expect($timeout,"User:"))  {
		die "Never got username prompt on $hostname, ".$telnet->exp_error()."\n";
	}


	#
	# send  "$NAME1\r"
	print $telnet  "$NAME1\r";


	#
	# send_user "\[Sent name;  waiting for password\]\n"
	# expect    "assword:"
	unless ($telnet->expect($timeout,"assword:"))  {
		die "Never got password prompt on $hostname, ".$telnet->exp_error()."\n";
	}


	#
	# send   "$PSWD1\r"
	print $telnet   "$PSWD1\r";



	#
	# Need a <CR> to get going!!
	# expect "begin logging on"
	unless ($telnet->expect($timeout,"begin logging on"))  {
		die "Never got 'begin logging on' prompt on $hostname, ".$telnet->exp_error()."\n";
	}


	#
	#           send   "\r"
	print $telnet   "\r";


	#
	# Now log onto the .....
	# expect     "Username:"
	# send "$NAME2\r"
	unless ($telnet->expect($timeout,"Username:"))  {
		die "Never got 2nd username prompt on $hostname, ".$telnet->exp_error()."\n";
	}
	print $telnet "$NAME2\r";




	#
	# expect     "Password:"
	# send "$PSWD2\r"
	unless ($telnet->expect($timeout,"Password:"))  {
		die "Never got 2nd password prompt on $hostname, ".$telnet->exp_error()."\n";
	}
	print $telnet "$PSWD2\r";




	#
	# Now we're logged on
	# download the data
	#
	# expect ">"
	unless ($telnet->expect($timeout,">"))  {
		die "Never got '>' prompt on $hostname, ".$telnet->exp_error()."\n";
	}



	#
	#    select whether we want to download message file, or platform ID
	if ($do_message_file)  {

		#
		# This was the old shorthand
		# send "do msg list_id 1\r"   
		# send "DOWNLOAD MESSAGE_FILE LIST_ID 1\r"
		# print $telnet  "download message_file list_id 1\r";
		# print $telnet  "download message_file list_id 2\r";
		print $telnet  "download message_file list_id $do_message_file\r";

	} else  {

		#
		#
		# This instead of previous for downloading OLD instead of new data
		# send "do msg platform_id $PLATFORM1\r"   
		print $telnet  "download message_file platform_id $PLATFORM1\r";
		# expect ">>"
		# send "Y\r"

	}   #  end if ... else


	unless ($telnet->expect($timeout,">>"))  {
		die "Never got '>>' prompt on $hostname, ".$telnet->exp_error()."\n";
	}


	#
	# start logging the data
	$telnet->log_file($logfile);
	print $telnet "Y\r";


	#
	# Need the following to wait before quitting!!
	#    expect ">";`
	#    send "bye\r";
	unless ($telnet->expect($timeout,">"))  {
		#die "Never got final '>' prompt on $hostname, ".$telnet->exp_error()."\n";
		print  "Never got final '>' prompt on $hostname, ".$telnet->exp_error()."\n";
		$telnet->log_file("/dev/null");
		print $telnet "bye\r";
	}


	#
	#  Close log file
	print $telnet "bye\r";


	#
	#      Wait until all output from TELNET session is finished
	unless ($telnet->expect($timeout,"nnection close"))  {
		die "Never got final 'Connection closed' prompt on $hostname, ".$telnet->exp_error()."\n";
	}



	return $logfile;

}