File: ecbler.sh
   1 #!/bin/sh
   2 
   3 # The MIT License (MIT)
   4 #
   5 # Copyright © 2020-2025 pacman64
   6 #
   7 # Permission is hereby granted, free of charge, to any person obtaining a copy
   8 # of this software and associated documentation files (the “Software”), to deal
   9 # in the Software without restriction, including without limitation the rights
  10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11 # copies of the Software, and to permit persons to whom the Software is
  12 # furnished to do so, subject to the following conditions:
  13 #
  14 # The above copyright notice and this permission notice shall be included in
  15 # all copies or substantial portions of the Software.
  16 #
  17 # THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23 # SOFTWARE.
  24 
  25 
  26 # ecbler
  27 # European Central Bank Latest Exchange Rates
  28 #
  29 # Emit the latest exchange rates against the euro as 2 lines, the first line
  30 # being a header with the column names.
  31 #
  32 # The numbers in the second line are what you multiply each foreign currency
  33 # to get its equivalent amount in euros.
  34 
  35 
  36 # handle leading options
  37 case "$1" in
  38     -h|--h|-help|--help)
  39         awk '/^# +ecbler/, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  40         exit 0
  41     ;;
  42 esac
  43 
  44 # load data from website
  45 wget -q -O - 'https://www.ecb.europa.eu/stats/eurofxref/eurofxref.zip' |
  46 # decompress payload
  47 gzip -d |
  48 # turn CSV into TSV, ignoring trailing empty fields
  49 sed -E 's- *\r$--; s-,$--; s-, *-\t-g; s-\t+$--' |
  50 # reciprocate dividers into multipliers
  51 awk -F "\t" '
  52 NR == 1 { print }
  53 NR == 2 {
  54     printf "%s", $1
  55     for (i = 2; i <= NF; i++) printf("\t%.6f", 1.0 / $i)
  56     printf "\n"
  57 }'
  58 
  59 # extending the pipe-chain to a step calling `column -t` realigns columns,
  60 # turning tabs into spaces