bufr.pm:bufrencode_source
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#!/usr/bin/perl -w
# (C) Copyright 2010, met.no
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.
# Encode a BUFR message, reading data and metadata from files.
# Author: P. Sannes met.no 2010
use strict;
use Getopt::Long;
# metno module
use BUFR;
use constant DEFAULT_TABLE_PATH => '/usr/local/lib/emos/bufrtables';
# Parse command line options
my %option = ();
GetOptions(
\%option,
'data=s',
'help',
'metadata=s',
'outfile=s',
'tablepath=s',
'verbose=i',
) or die "Wrong option(s), execute $0 without arguments for Usage\n";
# User asked for help
usage_verbose() if $option{help};
# Data or metadata file not provided
usage() if not $option{data} or not $option{metadata};
my $data_file = $option{data};
my $metadata_file = $option{metadata};
my $verbose = $option{verbose} ? $option{verbose} : 0;
# Set verbosity level for the BUFR module. Must be set also for each
# BUFR object generated
BUFR->set_verbose($verbose);
# Set BUFR table path
if ($option{tablepath}) {
# Command line option --tablepath overrides all
BUFR->set_tablepath($option{tablepath});
} elsif ($ENV{BUFR_TABLES}) {
# If no --tablepath option, use the BUFR_TABLES environment variable
BUFR->set_tablepath($ENV{BUFR_TABLES});
} else {
# If all else fails, use the libemos bufrtables
BUFR->set_tablepath(DEFAULT_TABLE_PATH);
}
# Read in metadata
my $metadata = read_metadata($metadata_file);
my $bufr = BUFR->new();
# This sets object verbose level equal to class verbose level
$bufr->set_verbose($verbose);
my $bufr_edition = $metadata->{BUFR_EDITION};
$bufr->set_bufr_edition($bufr_edition);
$bufr->set_master_table($metadata->{MASTER_TABLE});
$bufr->set_centre($metadata->{CENTRE});
$bufr->set_subcentre($metadata->{SUBCENTRE});
$bufr->set_update_sequence_number($metadata->{UPDATE_NUMBER});
$bufr->set_optional_section($metadata->{OPTIONAL_SECTION});
$bufr->set_data_category($metadata->{DATA_CATEGORY});
if ( $bufr_edition < 4 ) {
$bufr->set_data_subcategory($metadata->{DATA_SUBCATEGORY});
} else {
$bufr->set_int_data_subcategory($metadata->{INT_DATA_SUBCATEGORY});
$bufr->set_loc_data_subcategory($metadata->{LOC_DATA_SUBCATEGORY});
}
$bufr->set_master_table_version($metadata->{MASTER_TABLE_VERSION});
$bufr->set_local_table_version($metadata->{LOCAL_TABLE_VERSION});
if ( $bufr_edition < 4 ) {
$bufr->set_year_of_century($metadata->{YEAR_OF_CENTURY});
} else {
$bufr->set_year($metadata->{YEAR});
}
$bufr->set_month($metadata->{MONTH});
$bufr->set_day($metadata->{DAY});
$bufr->set_hour($metadata->{HOUR});
$bufr->set_minute($metadata->{MINUTE});
$bufr->set_second($metadata->{SECOND}) if $bufr_edition >= 4;
$bufr->set_observed_data($metadata->{OBSERVED_DATA});
$bufr->set_compressed_data($metadata->{COMPRESSED_DATA});
$bufr->set_descriptors_unexpanded($metadata->{DESCRIPTORS_UNEXPANDED});
$bufr->set_local_use($metadata->{LOCAL_USE}) if exists $metadata->{LOCAL_USE};
$bufr->load_BDtables();
# Read in the data (descriptors and values)
my ($data_refs, $desc_refs, $num_subsets) = readdata($data_file);
$bufr->set_number_of_subsets($num_subsets);
# Print the encoded BUFR message
if ($option{outfile}) {
open(my $OUT, '>',$option{outfile})
or die "Cannot open $option{outfile} for writing: $!";
print $OUT $bufr->encode_message($data_refs, $desc_refs);
close $OUT or die "Cannot close $option{outfile}: $!";
} else {
print $bufr->encode_message($data_refs, $desc_refs);
}
sub read_metadata {
my $file = shift;
open (my $fh, '<', $file) or die "Cannot open $file: $!";
my %metadata;
while ( <$fh> ) {
chomp;
next if /^\s*$/;
my ($key, $value) = split /\s+/, $_, 2;
$metadata{$key} = $value;
}
close $fh;
return \%metadata;
}
sub readdata {
my $file = shift;
open (my $fh, '<', $file) or die "Cannot open $file: $!";
my ($data_refs, $desc_refs);
my $subset = 0;
while ( <$fh> ) {
s/^\s+//;
next if not /^\d/;
my ($n, $desc, $value) = split /\s+/, $_, 3;
$subset++ if $n == 1;
$value =~ s/\s+$//;
$value = undef if $value eq '' or $value eq 'missing';
$data_refs->[$subset]->[$n-1] = $value;
$desc_refs->[$subset]->[$n-1] = $desc;
}
close $fh;
return ($data_refs, $desc_refs, $subset);
}
sub usage {
print <<"EOF";
Usage: $0
--data <data file>
--metadata <metadata file>
[--tablepath <path to BUFR tables>]
[--outfile <file to print encoded BUFR message(s) to>]
[--verbose n]
[--help]
Try '$0 --help' for more information.
EOF
exit 0;
}
sub usage_verbose {
print <<"EOF";
Will create a BUFR message printed to STDOUT based on data and metadata
in files <data file> and <metadata file> respectively.
Usage: $0 -d <data file> -m <metadata file>
or $0 --data <data file> --metadata <metadata file>
Options:
--help
Will print this help message and then exit
--outfile <filename>
Will print encoded BUFR messages to <filename> instead of STDOUT
--verbose n
Set verbose level to n, 0<=n<=3 (default 0). Verbose output is sent STDOUT,
so ought to be combined with option --outfile
--tablepath <path to BUFR tables>
If used, will set path to BUFR tables. If not set, will fetch tables
from the environment variable BUFR_TABLES, or if this is not set: will use
/usr/local/lib/emos/bufrtables/
For the metadata file, use this as prototype and change the values as desired:
BUFR_EDITION 4
MASTER_TABLE 0
CENTRE 98
SUBCENTRE 0
UPDATE_NUMBER 0
OPTIONAL_SECTION 0
DATA_CATEGORY 0
INT_DATA_SUBCATEGORY 0
LOC_DATA_SUBCATEGORY 255
MASTER_TABLE_VERSION 13
LOCAL_TABLE_VERSION 1
YEAR 2008
MONTH 9
DAY 1
HOUR 6
MINUTE 0
SECOND 0
OBSERVED_DATA 1
COMPRESSED_DATA 0
DESCRIPTORS_UNEXPANDED 308004 012005 002002
For BUFR edition < 4, replace the lines INT_DATA_SUBCATEGORY,
LOC_DATA_SUBCATEGORY, YEAR and SECOND with new lines DATA_SUBCATEGORY
and YEAR_OF_CENTURY (the order of lines doesn't matter).
For the data file, use the same format as would result if you did run
on the generated BUFR message
bufrread.pl <bufr file> --data_only | cut -c -31
(or if you use bufrread.pl with --width n, replace 31 with n+16).
For example, the file might begin with
1 001195 Newport
2 005002 51.55
3 006002 -2.99
4 004001 2008
...
Every time a new line starting with the number 1 is met, a new subset will be
generated in the BUFR message. Lines not starting with a number are ignored.
For missing values, use 'missing' or stop the line after the BUFR descriptor.
Associated values should use BUFR descriptor 999999.
To encode a NIL subset, all delayed replication factors should be set to 1, and
all other values set to missing except for the descriptors defining the station.
EOF
exit 0;
}
bufr.pm/bufrencode_source.1267015840.txt.gz · Last modified: (external edit)