Automatic PDF synchronisation between local and cloud storage, which takes care of collision

README.md

Automatic PDF synchronisation between local and Cloud Storage

This hook scripts allows you to synchronise PDF files whenever you make a commit which changes PDF-file. If the PDF on Cloud Storage is changed since the commit made, this script asks whether proceed overwriting, backup-ing or just abort.

The intended use is to sync PDF between local and Digital Paper Device, where DPD-version might contain "hand-written" notes.

It is also useful, when you use the same directory to sync with Cloud storage and Digital Paper Device.

Requirements

• Bash
• pdftk
• git

Usage

1. Place post-commit and pre-commit to your .git/hooks directory,
2. chmod +x .git/hooks/{pre-commit,post-commit},
3. Make some commit with PDF.

CAUTION: ABSOLUTELY NO WARRANTY; USE AT YOUR OWN RISK

post-commit

#!/bin/bash
# Don't forget to `chmod +x` this file.

echo "Post-commiting..."
CLOUD="/PATH/TO/CLOUD/STORAGE"
COMMIT=`git log -1 HEAD --format=%H`

for file in `git diff --name-only HEAD~..HEAD`;
do
    if [[ "${file}" =~ .*\.pdf ]]; then
        BASE=`basename "${file}" .pdf`
        TARGET="${CLOUD}/${BASE}.pdf"

        cat <<EOF | pdftk "${file}" update_info_utf8 - output "${TARGET}"
InfoKey: X-Commit
InfoValue: ${COMMIT}
EOF
    fi
done

pre-commit

#!/bin/sh

# Redirect output to stderr.
exec 1>&2

CLOUD="/PATH/TO/CLOUD/STORAGE"

for file in `git diff --cached --name-only HEAD`
do
    if [[ "${file}" =~ .*\.pdf ]] ; then
       BASE=`basename ${file} .pdf`
       TARGET="${CLOUD}/${file}"
       if [[ -f $TARGET ]]; then
         echo "There is conflict."
         OLD_CMT=`pdftk "${TARGET}" dump_data_utf8 \
                | grep -1 '^InfoKey: X-Commit' \
                | tail -n1 | awk -F' *: *' '{print $2}'`
         OldId1=`git cat-file -p "${OLD_CMT}:${BASE}.pdf" \
               | pdftk - dump_data | grep PdfID1 | awk -F': ' '{print $2}'`
         NewId1=`pdftk "${TARGET}" dump_data | grep PdfID1 | awk -F': ' '{print $2}'`
         if [[ "${OldId1}" != "${NewId1}" ]]; then
             echo '!!! There might be some note by digital paper.'
             open "${TARGET}"
             OVERWRITE=-1
             while [[ $OVERWRITE -eq -1 ]] ; do
                 read -p "!!! Do you really want to overwrite it? (y[es]/B[ackup]/n[o]) " ans
                 if [[ "${ans}" = "" ]] ; then
                     ans="b"
                 fi
                 case "${ans}" in
                     [Bb])
                         OVERWRITE=1
                         mv "${TARGET}" "${CLOUD}/${BASE}-${OLD_CMT}.pdf";;
                     [Yy])
                         OVERWRITE=1
                         rm "${TARGET}";;
                     [Nn])
                         echo "Abort"
                         exit 1;;
                     *)
                         echo "Please answer by y or n.";;
                 esac
             done
         fi
       fi
    fi
done