tame/build-aux/csvm-expand

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#!/usr/bin/awk -f
#
# Expands a "magic" CSV file into a normal CSV
#
# Copyright (C) 2014-2019 Ryan Specialty Group, LLC.
#
# 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 3 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, see <http://www.gnu.org/licenses/>.
#
# "Magic" CSVs simply exist to make life easier: they permit comments, blank
# lines, variables, sub-delimiter expansion, and any number of ranges per line.
# Ranges will be expanded in every combination, making rate tables highly
# maintainable.
#
# Variables are also supported when defined using :var=val. Variables may
# expand into ranges, 'cause they're awesome. Multiple variables may be
# delimited by semi-colons, as may multiple values.
#
# For example:
# :foo=1--3
# $foo;7;9--10:$foo, 5--10,1/1/2017
#
# Would generate:
# 1, 5, 1483246800
# 1, 6, 1483246800
# ...
# 5, 10, 1483246800
# 2, 5, 1483246800
# ...
# 9, 5, 14832468005
# ...
# 1, 5, 1483246800
# 1, 6, 1483246800
# ...
##
BEGIN {
date_cmd = "stdbuf -o0 date -f- +%s"
}
END {
close( date_cmd )
}
# Parse a date string into a Unix timestamp (memoized)
#
# This spawns a single process for date and reads from standard in. Even
# then, though, date parsing is very slow for many thousands of rows, so the
# output is also cached in `date_cache'.
function parse_date( i, src )
{
src = $i
if ( date_cache[ src ] )
{
$i = date_cache[ src ]
return
}
print $i |& date_cmd
date_cmd |& getline $i
date_cache[ src ] = $i;
}
# Expand variable with its value, if any
function expand_vars( s, value )
{
# attempt to parse variable (may expand into a range)
if ( match( s, /^\$([a-zA-Z_-]+)$/, m ) )
{
value = vars[ m[1] ];
if ( value == "" )
{
print "error: unknown variable reference: `$" m[1] "'" > "/dev/stderr"
exit 1
}
return value
}
return s
}
# Expand line
function parseline( i, m, j, me, orig )
{
if ( i > NF )
{
print
return
}
orig = $i
# expand variables before any processing so that expansions
# can include any type of formatting
$i = expand_vars( $i )
if ( match( $i, /^([0-9]+\/){2}[0-9]+$/, m ) )
{
parse_date( i );
}
# check first for delimiters
if ( match( $i, /^([^;]+);(.*)$/, m ) )
{
# give it a shot with the first value
$i = m[1]
parseline( i )
# strip off the first value and process with following value(s)
$i = m[2]
parseline( i )
# we've delegated; we're done
$i = orig
return
}
# parse range
if ( match( $i, /^([^-]+)--([^-]+)$/, m ) )
{
j = expand_vars( m[1] )
me = expand_vars( m[2] )
if ( !match( j, /^[0-9]+$/ ) || !match( me, /^[0-9]+$/ ) )
{
print "error: invalid range: `" $i "'" > "/dev/stderr"
exit 1
}
do
{
$i = j
parseline( i + 1 )
} while ( j++ < me )
}
else
{
parseline( i + 1 );
}
# restore to original value
$i = orig
}
BEGIN {
# we're parsing CSVs
FS = "[[:space:]]*,[[:space:]]*"
OFS = ","
has_directives = 0
directives = "!(NODIRECTIVES)"
}
# skip all lines that begin with `#', which denotes a comment, or are empty
/^#|^$/ { next; }
# directives are echoed back and are intended for processing by
# the parent csvm2csv script
/^!/ && output_started {
print "error: directive must appear before header: `" $0 "'" > "/dev/stderr"
exit 1
}
/^!/ && has_directives {
print "error: all directives must be on one line: `" $0 "'" > "/dev/stderr"
exit 1
}
/^!/ {
has_directives = 1
directives = $0
next
}
# lines that begin with a colon are variable definitions
/^:/ {
if ( !match( $0, /^:([a-zA-Z_-]+)=(.*?)$/, m ) )
{
print "error: invalid variable definition: `" $0 "'" > "/dev/stderr"
exit 1
}
vars[ m[1] ] = m[2]
next
}
# Always begin output with a line for directives, even if there are
# none. This makes subsequent processing much easier, since we won't have
# to conditionally ignore the top line.
!output_started {
print directives
output_started = 1
}
# lines that need any sort of processing (ranges, dates, etc)
/--|;|\$[a-zA-Z_-]|\// { parseline( 1 ); next; }
# all other lines are normal; simply output them verbatim
{
# this assignment will ensure that awk processes the output, ensuring that
# extra spaces between commas are stripped
$1=$1
print
}