Rename PDF as AuthorYear.pdf from Crossref DOI data

rename_pdf_doi.sh

# Used as an embedded shell script in Hazel for files where a DOI is available
# 
# Depedencies:
# - pdfgrep
# - curl
# - jq

newname=$(pdfgrep -oPm 1 --page-range=1-2 '\b10.\d{4,9}/[-._;()/:A-Za-z0-9]+\b' $1 |
  xargs -I{} curl -sLH "Accept: application/json" http://dx.doi.org/{} |
  jq '.author[0].family, .issued."date-parts"[0][0]' |
  tr '\n' ' ' |
  sed 's/[" ]//g')

# Check that $newname is not empty (in case there was an error) before renaming
if [[ ! -z "$newname" ]]; then
  mv $1 "$newname.pdf"
fi