doi2bibtex

#!/bin/bash
#
# Get a BibTeX citation from a DOI
set -e
set -o pipefail

usage()
{
  echo "usage : doi2bibtex [ -d DOI ] [ -f FILE ]"
  echo ""
  echo "A simple Bash script to take a single DOI or a list of DOIs from a file"
  echo "and use cURL to fetch the BibTeX citation for the given DOI(s)."
  echo ""
  echo "If no DOI or file is provided the adjacent README.md is parsed for DOIs"
  echo "using cat/grep/awk. Note that the URL for the DOI MUST be the last"
  echo "element of the row and separated by a space from the previous word."
}


while getopts "d:f:?h" option
do
    case $option in
	d)
	    DOI=${OPTARG};;
	f)
	    FILE=${OPTARG};;
	h|?)
            usage
            exit 0;;
    esac
done

DOI_FILE=()

if [ "${FILE}" ]; then
  while IFS= read -r LINE; do
    DOI_FILE+=("${LINE}")
  done < "${FILE}"
fi

if [ "${DOI}" ]; then
  DOI_FILE+=("${DOI}")
fi

if [ -p /dev/sdtin ]; then
  while IFS= read -r LINE; do
    DOI_FILE+=("${LINE}")
  done
fi

if [ -z "${FILE}" ] && [ -z "${DOI}" ]; then
  mapfile -t DOI_FILE < <(grep "^\*" README.md | grep "doi" | awk '{print $NF}')
fi

_fetch()
{
  DOI=${1}
  # Pipe through grep so that only valid references are output, we capture non-matches (when grep returns 1)
  curl --silent -LH "Accept: text/bibliography; style=bibtex" ${DOI} | { grep "^ @" || test $? = 1; }
}


for doi in "${DOI_FILE[@]}"; do
  _fetch ${doi}
done