add backup.sh (closes #2)

backup.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+# exit when any step fails
+set -euo pipefail
+
+# default paths
+MASTODON_ROOT=/home/mastodon
+APP_ROOT="$MASTODON_ROOT/live"
+BACKUPS_ROOT="$MASTODON_ROOT/backups"
+
+if [ "$(systemctl is-active mastodon-web.service)" = "active" ]
+then
+  echo "⚠️  Mastodon is currently running."
+  echo "We'll start the backup anyways, but if it's a critical one, stop all Mastodon"
+  echo "services first with 'systemctl stop mastodon-*' and run this again."
+  echo ""
+fi
+
+if [ ! -d "$BACKUPS_ROOT" ]
+then
+  sudo mkdir -p "$BACKUPS_ROOT"
+  sudo chown -R mastodon:mastodon "$BACKUPS_ROOT"
+fi
+
+TEMP_DIR=$(sudo -u mastodon mktemp -d)
+
+echo "Backing up Postgres..."
+sudo -u mastodon pg_dump -Fc mastodon_production -f "$TEMP_DIR/postgres.dump"
+
+echo "Backing up Redis..."
+sudo cp /var/lib/redis/dump.rdb "$TEMP_DIR/redis.rdb"
+
+echo "Backing up secrets..."
+sudo cp "$MASTODON_ROOT/live/.env.production" "$TEMP_DIR/env.production"
+
+echo "Compressing..."
+ARCHIVE_DEST="$BACKUPS_ROOT/$(date "+%Y.%m.%d-%H.%M.%S").tar.gz"
+sudo tar --owner=0 --group=0 -czvf "$ARCHIVE_DEST" -C "$TEMP_DIR" .
+sudo chown mastodon:mastodon "$ARCHIVE_DEST"
+
+sudo rm -rf --preserve-root "$TEMP_DIR"
+
+echo "Saved to $ARCHIVE_DEST"
+echo "🎉 All done! (Keep this archive safe!)"