Backup key info from a mastodon account

mastodon-backup.sh

#!/bin/bash

# Requires:
# - bash
# - mmv: usually in an "mmv" package
# - madonctl: https://github.com/McKael/madonctl
# - One of hardlink, xz, gzip or bzip2, depending on COMPRESSEXT

# Set up madonctl per instructions, so that it's linked to your instance and account.

# Settings
PATH=$PATH:/root/bin
DIR=/opt/mastodon-backup/
KEEP=45
SLEEP=30s
COMPRESSEXT="" # '', '.xz', '.gz', '.bz2'
FIELDS="Account ID:|User ID:|URL:|^-"

cd $DIR

# If rotated this far, remove oldest backup:
rm -vf *.${KEEP}${COMPRESSEXT}

# Rotate backups, so that *.10 becomes *.11, *.0 becomes *.1, etc
for i in $(seq ${KEEP} -1 1); do
  j=$((${i}-1))
  mmv "*.${j}${COMPRESSEXT}" "#1.${i}${COMPRESSEXT}" &> /dev/null
done

# Stuff at the "account" endpoint:
for acctthing in following followers blocks muted show favourites; do
  madonctl accounts ${acctthing} --all | egrep "$FIELDS" > accounts-${acctthing}.0
  sleep $SLEEP
done

# Domain blocks
madonctl domain-blocks --show > domain-blocks.0
sleep $SLEEP

# Get list of lists
madonctl lists show --all > lists.0

# Get membership of each list
for list in $(grep 'List ID:' lists.0 | cut -d: -f2); do
  sleep $SLEEP
  madonctl lists accounts --list-id $list | egrep "$FIELDS" > list-$list.0
done

# Delete any empty lists, except latest
find . -size 0 -not -name \*.0 -delete

# Compress files or hardlink identical files
# If KEEP is high and files don't change often, "hardlink" likely most efficient option
case $COMPRESSEXT in
  .xz)
    xz *.0
    ;;
  .gz)
    gzip *.0
    ;;
  .bz2)
    bzip2 *.0
    ;;
  *)
    hardlink --ignore-time --keep-oldest --maximize .
    ;;
esac