flightgear/utils/metarproxy/metarproxy
2022-10-20 20:29:11 +08:00

522 lines
13 KiB
Perl
Executable File

#!/usr/bin/perl -w
# FlightGear METAR proxy server
# Melchior FRANZ (c) 2005, <mfranz # aon : at>, GPL V2
# $Id$
#
# typical use
# 1) fill cache, for example with:
# $ metarproxy --download 3h
#
# 2) run proxy with FlightGear:
# $ metarproxy -c -v &
# $ fgfs --enable-real-weather-fetch --proxy=localhost:5509 --start-date-lat=2005:01:11:12:00:00
use strict;
use IO::Socket;
use Net::hostent;
use Time::Local;
my $HOME = $ENV{'HOME'} || ".";
my $FG_HOME = $ENV{'FG_HOME'} || $HOME . "/.fgfs";
my $BASE = $FG_HOME . "/metar";
my $SERVER = "tgftp.nws.noaa.gov";
my $PORT = 5509;
my $PROXY = $ENV{'http_proxy'};
my $METAR_MAX_AGE = 250 * 60;
my $METAR_DEFAULT = "00000KT 15KM CLR 15/00 A3000";
my @COLOR = ("31;1", "31", "32", "", "36;1");
my $USECOLOR = 0;
my $help = <<EOF;
Usage:
metarproxy [-v] [-b <path>] [-p <port>] [--serve]
metarproxy [-v] [-b <path>] [-y <proxy>] --download <list of: all|7|0-10|6h>
metarproxy [-v] [-b <path>] [-y <proxy>] --record [<list of station IDs>] [-f <path>]
metarproxy [-v] [-b <path>] --install <list of metar files>
metarproxy [-V]
metarproxy [-h]
server mode:
-s|--serve start proxy server (default)
-p|--port set port (default: $PORT)
download mode:
-d|--download <list of hours>
"all" ... whole day (24 files)
<number> ... this hour (example: 6)
<range> ... these hours (example: 2-5)
<period> ... last n hours (example: 3h)
-y|--proxy use proxy (default: off)
install mode:
-i|--install <list of files to install>
record mode:
-r|--record <list of METAR station IDs (ICAO)>
-f|--file <file containing list of station IDs>
-y|--proxy use proxy (default: off)
all modes:
-b|--base set base directory (default: \$FG_HOME/metar)
-c|--color toggle color mode (default: off)
-v|--verbose increase verbosity level (default: off; maximum: -vvvv)
-q|--quiet only show error messages
-h|--help this help
-V|--version return version number
Environment:
FG_HOME ... FlightGear home directory (default: \$HOME/.fgfs)
METARPROXY ... default options (e.g. export METARPROXY='-vv --color')
http_proxy ... system wide proxy setting (currently: '$PROXY')
Examples:
\$ metarproxy -b\$HOME/.fgfs/metar --download 3h
\$ metarproxy --proxy=http://localhost:3128 --download all
\$ metarproxy --download 3h 7 21-23
\$ metarproxy --record -f/tmp/list LOWW LOWL
\$ metarproxy -b/var/tmp/metar --install /tmp/*Z.TXT
\$ metarproxy -p5600 & fgfs --proxy=localhost:5600 --enable-real-weather-fetch
\$ http_proxy= metarproxy --record LOXL
Sources:
http://tgftp.nws.noaa.gov/data/observations/metar/{stations,cycles}/
ftp://tgftp.nws.noaa.gov/data/observations/metar/{stations,cycles}/
EOF
my $ERR = 0;
my $WARN = 1;
my $INFO = 2;
my $BULK = 3;
my $DEBUG = 4;
my $VERBOSITY = $INFO;
my @ITEMS;
my $PROXYHOST;
my $PROXYPORT;
# main =======================================================================
sub parse_options()
{
sub argument {
map { return $_ if defined $_ and $_ ne "" } @_;
shift @ARGV;
return $ARGV[0];
}
my $mode = 4;
unshift @ARGV, split /\s+/, $ENV{'METARPROXY'} if defined $ENV{'METARPROXY'};
while (1) {
$_ = $ARGV[0];
defined $_ or last;
if (!/^-/) {
push @ITEMS, $_;
} elsif (/^(-d|--download)$/) {
$mode = 1;
} elsif (/^(-i|--install)$/) {
$mode = 2;
} elsif (/^(-r|--record)$/) {
$mode = 3;
} elsif (/^(-s|--server?)$/) {
$mode = 4;
} elsif (/^(-b(.*)|--base(=(.*))?)/) {
my $path = &argument($2, $4);
defined $path or &fatal("-b|--base option lacks <path> argument");
$path =~ s/^~/$HOME/;
$BASE = $path;
&log($BULK, "set option --base: '$BASE'");
} elsif (/^(-f(.*)|--file(=(.*))?)$/) {
my $file = &argument($2, $4);
defined $file or &fatal("-f|--file option lacks <path> argument");
&log($BULK, "set option --file: '$file'");
&read_icao_file($file);
} elsif (/^(-p(.*)|--port(=(.*))?)$/) {
$PORT = &argument($2, $4);
defined $PORT or &fatal("--port option lacks <port number> argument");
&log($BULK, "set option --port: '$PORT'");
} elsif (/^(-y(.*)|--proxy(=(.*))?)$/) {
$PROXY = &argument($2, $4);
defined $PROXY or &fatal("--proxy option lacks <host> definition");
&log($BULK, "set option --proxy: '$PROXY'");
} elsif (/^--verbose$/) {
$VERBOSITY++;
} elsif (/^-(v+)$/) {
$VERBOSITY += length($1);
} elsif (/^(-q|--quiet)$/) {
$VERBOSITY = 0;
} elsif (/^(-h|--help)$/) {
print $help;
return 0;
} elsif (/^(-V|--version)$/) {
($_ = '$Revision$') =~ s/.*(\d+\.\d+).*/print "$1\n"/e;
return 0;
} elsif (/^(-c|--color)$/) {
$USECOLOR = !$USECOLOR;
} else {
&fatal("unknown option $_");
}
shift @ARGV;
}
return $mode;
}
sub main()
{
undef $PROXY if $PROXY eq "";
my $mode = &parse_options();
exit if $mode == 0;
-d $FG_HOME or mkdir $FG_HOME or &fatal("cannot create directory $FG_HOME ($!)");
-d $BASE or mkdir $BASE or &fatal("cannot create directory $BASE ($!)");
if (defined $PROXY) {
$PROXY =~ m|^(http://)?([a-zA-Z][a-zA-Z0-9-.]*):(\d+)/?| or &fatal("invalid proxy address: '$PROXY'");
($PROXYHOST, $PROXYPORT) = ($2, $3);
}
my $ret = 0;
if ($mode == 1) {
$ret = &download;
} elsif ($mode == 2) {
$ret = &install();
} elsif ($mode == 3) {
$ret = &record();
} elsif ($mode == 4) {
&log($ERR, "ignoring command line args: " . (join ", ", @ITEMS)) if @ITEMS;
$ret = &serve();
}
exit $ret;
}
sub read_icao_file($)
{
my $path = shift;
$path =~ s/^\~/$HOME/;
if (!open(F, "<$path")) {
&log($ERR, "cannot open station list $path ($!)");
return;
}
while (<F>) {
s/\s+$//;
foreach (split) {
if (/^[A-Z][A-Z0-9]{3}$/) {
push @ITEMS, $_;
} else {
&log($ERR, "discarding suspicious station from $path: $_");
}
}
}
close F or &log($ERR, "cannot close station list $path ($!)");
}
# download ===================================================================
sub download()
{
my %h;
sub norm {
my $i = shift;
$i = 0 if $i < 0;
$i = 23 if $i > 23;
return $i;
}
foreach (@ITEMS) {
if (/^all$/) {
map { $h{$_} = 1 } (0 .. 23);
} elsif (/^(\d+)-(\d+)$/) {
map { $h{$_} = 1 } (&norm($1) .. &norm($2));
} elsif (/^(\d+)h$/) {
my $to = (gmtime(time))[2];
my $from = $to - &norm($1) + 1;
if ($from < 0) {
map { $h{$_} = 1 } ((24 + $from) .. 23);
$from = 0;
}
map { $h{$_} = 1 } ($from .. $to);
} elsif (/^(\d+)$/) {
$h{&norm($1)} = 1;
} else {
&log($ERR, "illegal download argument '$_' ignored");
}
}
@ITEMS = sort { $a <=> $b } keys %h;
@ITEMS or &fatal("nothing to download");
&log($INFO, "downloading: " . (join ", ", @ITEMS));
foreach (@ITEMS) {
my $file = sprintf "/pub/data/observations/metar/cycles/%02dZ.TXT", $_;
&install_metar_http($SERVER, "80", $file);
}
return 0;
}
# install ====================================================================
sub install()
{
foreach my $file (@ITEMS) {
&log($INFO, "installing $file");
if (! -f $file) {
&log($ERR, "file $file doesn't exist");
next;
}
if (!open (IN, "<$file")) {
&log($ERR, "cannot open $file ($!)");
next;
}
local $/ = "";
&install_metar($_) foreach <IN>;
close IN or &log($ERR, "cannot close $file ($!)");
}
return 0;
}
# install a METAR string KSFO under $FG_HOME/metar/2005-01-12/K/KS/KSFO
sub install_metar($)
{
my $metar = shift;
return unless $metar =~ /^(\d{4})\/(\d+)\/(\d+)\s(\d+):(\d+).*\015?\012([A-Z])([A-Z0-9])([A-Z0-9]{2})\s/s;
my $name = sprintf "$BASE/%04d-%02d-%02d", $1, $2, $3;
-d $name or mkdir $name or &fatal("cannot create directory $name ($!)");
$name .= "/$6";
-d $name or mkdir $name or &fatal("cannot create directory $name ($!)");
$name .= "/$6$7";
-d $name or mkdir $name or &fatal("cannot create directory $name ($!)");
$name .= "/$6$7$8";
my $found;
if (open(F, "<$name")) {
local $/ = "";
while (<F>) {
if (m|^$1/$2/$3 $4:$5\s|s) {
$found = 1;
last;
}
}
close F or &log($ERR, "cannot close file $name ($!)");
return if defined $found;
}
&log($INFO, "writing to $name");
open(F, ">>$name") or &fatal("cannot append to file $name ($!)");
print F $metar;
close F or &log($ERR, "cannot close file $name ($!)");
}
sub install_metar_http($$$)
{
my ($server, $port, $addr) = @_;
&log($INFO, "installing data from http://$server:$port$addr");
if (defined $PROXYHOST) {
&log($INFO, "via proxy http://$PROXYHOST:$PROXYPORT");
$addr = "http://$server" . $addr;
($server, $port) = ($PROXYHOST, $PROXYPORT);
}
my $socket = IO::Socket::INET->new(Proto => "tcp", PeerAddr => $server, PeerPort => $port);
$socket or &fatal("cannot connect to http://$server:$port$addr/ ($!)");
$socket->autoflush(1);
my $get = "GET $addr HTTP/1.0";
print $socket "$get\015\012\015\012";
&log($DEBUG, ":$get:");
# skip header
while (<$socket>) {
s/\s*$//;
last if /^$/;
&log($DEBUG, "[$_]");
}
local $/ = "";
foreach (<$socket>) {
&install_metar("$_\n");
}
close($socket) or &log($ERR, "cannot close INET socket ($!)");
return 0;
}
# record =====================================================================
sub record()
{
@ITEMS or &fatal("no stations given");
my %h;
# check for validity and remove duplicates
foreach (@ITEMS) {
if (/^[A-Z][A-Z0-9]{3}$/) {
$h{$_} = 1;
} else {
&log($ERR, "discarding invalid station '$_'");
}
}
@ITEMS = sort keys %h;
&log($INFO, "recording stations @ITEMS");
while (1) {
foreach (@ITEMS) {
&install_metar_http($SERVER, "80", "/pub/data/observations/metar/stations/$_.TXT");
}
&log($INFO, "sleeping ...");
sleep 15 * 60
}
}
# serve ======================================================================
sub serve()
{
my $server = IO::Socket::INET->new(Proto => 'tcp', LocalPort => $PORT, Listen => SOMAXCONN, Reuse => 1);
$server or &fatal("cannot setup server ($!)");
&log($BULK, "server $0 accepting clients on port $PORT");
my %last_metar;
while (my $client = $server->accept()) {
$client->autoflush(1);
my $hostinfo = gethostbyaddr($client->peeraddr);
my $clientname = $hostinfo->name || $client->peerhost;
my $addr = inet_ntoa(inet_aton($clientname));
my ($icao, $epoch);
while (<$client>) {
s/\s+$//;
&log($DEBUG, $_);
if (m|^GET\s+http://tgftp.nws.noaa.gov/.*/([A-Z][A-Z0-9]{3}).TXT\s+HTTP/|) {
$icao = $1;
} elsif (/X-Time: (\d+)/) {
$epoch = $1;
} elsif (/^$/) {
last;
} else {
&log($INFO, "$_") if $VERBOSITY < $DEBUG;
}
}
if (defined $icao and defined $epoch) {
my ($min, $hour, $day, $mon, $year) = (gmtime($epoch))[1 .. 5];
$year += 1900;
$mon++;
&log($BULK, sprintf "client '$clientname' [$addr] requests data for station $icao "
. "at %04d/%02d/%02d %02d:%02d", $year, $mon, $day, $hour, $min);
my ($metar, $age) = &get_metar($icao, $epoch);
if (defined $metar) {
if ($age <= $METAR_MAX_AGE) {
&log($BULK, "found (" . int($age / 60) . " min old)");
$metar =~ s/\s*$//s;
$last_metar{$addr} = $metar;
$last_metar{$addr} =~ s/.*\015?\012[A-Z0-9]{4}\s+[0-9]{6}Z\s+//s;
&log($DEBUG, "setting default for [$addr] to '$last_metar{$addr}'");
$metar =~ s/\015?\012/\015\012/g;
} else {
&log($INFO, "found, but too old (" . int($age / 60) . " min)");
undef $metar;
}
} else {
&log($WARN, "not found!");
}
if (!defined $metar) {
&log($INFO, "sending last successful data again");
$metar = sprintf "%04d/%02d/%02d %02d:%02d\015\012",
$year, $mon, $day, $hour, $min;
$metar .= sprintf "$icao %02d%02d%02dZ ", $day, $hour, $min;
$metar .= $last_metar{$addr} || $METAR_DEFAULT;
}
print $client "HTTP/1.0 200 OK\015\012";
print $client "Content-Type: text/plain\015\012"
. "X-MetarProxy: nasse Maus\015\012"
. "\015\012"
. "$metar\015\012";
&log($INFO, $metar);
} else {
&log($WARN, "incomplete request");
}
&log($BULK, "closing connection");
close $client;
}
}
sub get_metar($$)
{
my $icao = shift;
my $rq_epoch = shift;
$icao =~ /^([A-Z])([A-Z0-9])([A-Z0-9]{2})$/;
sub scan_file($$) {
my $time = shift;
my $list = shift;
my ($hour, $day, $mon, $year) = (gmtime($time))[2 .. 5];
my $name = sprintf "$BASE/%04d-%02d-%02d/$1/$1$2/$1$2$3", $year + 1900, $mon + 1, $day;
if (open (F, "<$name")) {
&log($BULK, "reading $name");
local $/ = "";
push @$list, <F>;
close F or &log($ERR, "cannot close file $name ($!)");
} else {
&log($BULK, "no file $name to read ($!)");
}
return $hour < 2;
}
my @list; # "today" (and maybe "yesterday")
&scan_file($rq_epoch, \@list) and &scan_file($rq_epoch - 24 * 60 * 60, \@list);
my $age = 99999999;
my ($epoch, $metar);
foreach (@list) {
/^(\d{4})\/(\d+)\/(\d+)\s(\d+):(\d+).*\015?\012$icao\s/s or next;
$epoch = timegm(0, $5, $4, $3, $2 - 1, $1 - 1900);
next if $epoch > $rq_epoch; # lies in the future
next if $rq_epoch - $epoch > $age; # older than previous entry
$metar = $_;
$age = $rq_epoch - $epoch;
}
return ($metar, $age);
}
# ==================================================================
sub fatal()
{
&log($ERR, "$0: @_");
exit -1;
}
sub log()
{
my $v = shift;
return if $v > $VERBOSITY;
$v = 4 if $v > 4;
print "\033[$COLOR[$v]m" if $USECOLOR;
print "@_";
print "\033[m" if $USECOLOR;
print "\n";
}
main