franta-hg@0: #!/bin/bash
franta-hg@0: 
franta-hg@0: # VCS Backup
franta-hg@0: # Copyright © 2019 František Kučera (Frantovo.cz, GlobalCode.info)
franta-hg@0: #
franta-hg@0: # This program is free software: you can redistribute it and/or modify
franta-hg@0: # it under the terms of the GNU General Public License as published by
franta-hg@0: # the Free Software Foundation, either version 3 of the License, or
franta-hg@0: # (at your option) any later version.
franta-hg@0: #
franta-hg@0: # This program is distributed in the hope that it will be useful,
franta-hg@0: # but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@0: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@0: # GNU General Public License for more details.
franta-hg@0: #
franta-hg@0: # You should have received a copy of the GNU General Public License
franta-hg@0: # along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@0: 
franta-hg@0: 
franta-hg@0: # Server-side configuration:
franta-hg@0: VCS_BACKUP_DATA_DIR="/mnt/data";
franta-hg@0: VCS_BACKUP_CURRENT_DIR="$VCS_BACKUP_DATA_DIR/current";
franta-hg@2: VCS_BACKUP_PUBLIC_DIR="$VCS_BACKUP_DATA_DIR/public";
franta-hg@0: VCS_BACKUP_CONFIG_DIR="$VCS_BACKUP_DATA_DIR/config";
franta-hg@0: VCS_BACKUP_SNAPSHOT_DIR="$VCS_BACKUP_DATA_DIR/snapshot";
franta-hg@0: VCS_BACKUP_SUBVOLUME_SOCKET="/run/vcs-backup-subvolume";
franta-hg@0: VCS_BACKUP_CLONE_SOCKET="/run/vcs-backup-clone";
franta-hg@3: VCS_BACKUP_CLONE_CALLBACK_SOCKET="clone-callback";
franta-hg@0: VCS_BACKUP_USER="vcs-backup";
franta-hg@0: VCS_BACKUP_MANAGER="vcs-backup-manager";
franta-hg@0: 
franta-hg@0: # Installation – check and do it by hand:
franta-hg@0: # There should be already mounted Btrfs at $VCS_BACKUP_DATA_DIR
franta-hg@0: installInstructions() {
franta-hg@0: cp vcs-backup.sh /usr/local/bin/
franta-hg@0: adduser --disabled-password "$VCS_BACKUP"
franta-hg@0: adduser --disabled-password "$VCS_BACKUP_MANAGER"
franta-hg@0: 
franta-hg@0: mkdir "$VCS_BACKUP_CURRENT_DIR";
franta-hg@0: mkdir "$VCS_BACKUP_CONFIG_DIR";
franta-hg@0: mkdir "$VCS_BACKUP_SNAPSHOT_DIR";
franta-hg@0: 
franta-hg@0: chown "${VCS_BACKUP_USER}:${VCS_BACKUP_USER}" "$VCS_BACKUP_CURRENT_DIR"
franta-hg@0: chown "${VCS_BACKUP_MANAGER}:${VCS_BACKUP_MANAGER}" "$VCS_BACKUP_CONFIG_DIR"
franta-hg@0: }
franta-hg@0: 
franta-hg@0: 
franta-hg@0: # --- Private functions: ---------------------------------------------------------------------------
franta-hg@0: 
franta-hg@0: # Environment: all
franta-hg@0: # $1 = VCS type: hg, git
franta-hg@0: # $2 = URL
franta-hg@0: isValidTypeAndURL() { ([[ "$1" == "hg" || "$1" == "git" ]]) && [[ $(echo "$2" | wc -l) == 1 ]] && [[ $(echo "$2" | grep -E '^(http|https|ssh)://([a-zA-Z0-9_-][a-zA-Z0-9_-.]*/?)+$' | wc -l) == 1 ]]; }
franta-hg@0: 
franta-hg@0: # Environment: all
franta-hg@0: # $1 = path to the config file
franta-hg@0: loadConfigFile() { if [ -f "$1" ]; then . "$1"; else echo "Missing config file: $1" >&2; exit 1; fi }
franta-hg@0: 
franta-hg@0: # Environment: server
franta-hg@0: # $1 = URL
franta-hg@0: urlToRelativeDirectoryPath() {
franta-hg@0: 	echo "$1" | sed -E 's@^[^:]+://@@g';
franta-hg@0: }
franta-hg@0: 
franta-hg@0: # --- Public interface functions: ------------------------------------------------------------------
franta-hg@0: 
franta-hg@0: # Environment: client
franta-hg@0: # $1 = VCS type: hg, git
franta-hg@0: # $2 = URL
franta-hg@2: # $3 = "public" or "private" (default), whether the repository should be available through the public web interface
franta-hg@0: vcs_backup_public_clientSubmitBackupRequest() {
franta-hg@0: 	if isValidTypeAndURL "$1" "$2"; then
franta-hg@0: 		loadConfigFile ~/.config/vcs-backup/client.cfg
franta-hg@3: 		${VCS_BACKUP_SSH_COMMAND[@]} vcs-backup.sh serverSubmitBackupRequest "$1" "$2" "$3" "$4"
franta-hg@3: 		if [[ "$4" == "clone" ]]; then
franta-hg@3: 			if   [[ "$1" == "hg"  ]]; then  hg clone "ssh://${VCS_BACKUP_SERVER}//mnt/data/current/$1/$(urlToRelativeDirectoryPath $2)";
franta-hg@3: 			elif [[ "$1" == "git" ]]; then git clone "ssh://${VCS_BACKUP_SERVER}//mnt/data/current/$1/$(urlToRelativeDirectoryPath $2)";
franta-hg@3: 			fi
franta-hg@3: 		fi
franta-hg@0: 	else
franta-hg@0: 		echo "Unsupported VCS type: '$1' or URL: '$2'" >&2;
franta-hg@0: 	fi
franta-hg@0: }
franta-hg@0: 
franta-hg@0: # Environment: server
franta-hg@2: # has same parameters as clientSubmitBackupRequest (see above)
franta-hg@0: vcs_backup_public_serverSubmitBackupRequest() {
franta-hg@0: 	if isValidTypeAndURL "$1" "$2"; then
franta-hg@0: 		loadConfigFile "/etc/vcs-backup/server.cfg";
franta-hg@0: 		relativePath=$1/$(urlToRelativeDirectoryPath "$2");
franta-hg@0: 		absolutePath="$VCS_BACKUP_CONFIG_DIR/$relativePath";
franta-hg@0: 		mkdir -p "$absolutePath";
franta-hg@0: 		echo "$2" > "$absolutePath/url.txt"
franta-hg@0: 		echo "submited" > "$absolutePath/state.txt"
franta-hg@0: 		setfacl -m u:${VCS_BACKUP_USER}:r  "$absolutePath/url.txt"
franta-hg@0: 		setfacl -m u:${VCS_BACKUP_USER}:rw "$absolutePath/state.txt"
franta-hg@0: 		echo "$relativePath" | socat -u - unix-send:${VCS_BACKUP_SUBVOLUME_SOCKET};
franta-hg@3: 
franta-hg@2: 		if [[ "$3" == "public" ]]; then
franta-hg@2: 			cd "$VCS_BACKUP_PUBLIC_DIR";
franta-hg@2: 			mkdir -p "$(dirname $relativePath)";
franta-hg@2: 			ln -rs "../current/$relativePath" "$(dirname $relativePath)";
franta-hg@2: 		fi
franta-hg@3: 
franta-hg@3: 		if [[ "$4" == "clone" ]]; then
franta-hg@3: 			socat -u "unix-recvfrom:$absolutePath/${VCS_BACKUP_CLONE_CALLBACK_SOCKET},mode=777" - | while read m; do # TODO: ,group=${VCS_BACKUP_USER} and no 777
franta-hg@3: 				echo "Message from the clone service: $m";
franta-hg@3: 			done;
franta-hg@3: 		fi
franta-hg@0: 	else
franta-hg@0: 		echo "Unsupported VCS type: '$1' or URL: '$2'" >&2;
franta-hg@0: 	fi
franta-hg@0: }
franta-hg@0: 
franta-hg@0: # Environment: server
franta-hg@0: # Should be started as a systemd/init service.
franta-hg@0: # - reads messages from from the subvolume socket – message contains the relative directory path
franta-hg@0: # - creates a subvolume for given repository + necesary parent directories
franta-hg@0: # - sends a message to the clone service → start cloning into the created subvolume
franta-hg@0: vcs_backup_public_serverStartSubvolumeService() {
franta-hg@0: 	socat -u "unix-recv:${VCS_BACKUP_SUBVOLUME_SOCKET},group=${VCS_BACKUP_MANAGER},mode=770" - | while read d; do
franta-hg@0: 		mkdir -p $(dirname "$VCS_BACKUP_CURRENT_DIR/$d");
franta-hg@0: 		btrfs subvolume create "$VCS_BACKUP_CURRENT_DIR/$d" && \
franta-hg@0: 		echo "subvolumeCreated" > "$VCS_BACKUP_CONFIG_DIR/$d/state.txt" && \
franta-hg@0: 		chown "${VCS_BACKUP_USER}:${VCS_BACKUP_USER}" "$VCS_BACKUP_CURRENT_DIR/$d" && \
franta-hg@0: 		echo "$d" | socat -u - unix-send:${VCS_BACKUP_CLONE_SOCKET};
franta-hg@0: 	done
franta-hg@0: }
franta-hg@0: 
franta-hg@0: # Environment: server
franta-hg@0: # should be started as a systemd/init service
franta-hg@0: vcs_backup_public_serverStartCloneService() {
franta-hg@0: 	socat -u "unix-recv:${VCS_BACKUP_CLONE_SOCKET},mode=700" - | while read d; do
franta-hg@2: 		vcsType=$(echo "$d" | sed 's@/.*@@g');
franta-hg@0: 		url=$(cat "$VCS_BACKUP_CONFIG_DIR/$d/url.txt");
franta-hg@3: 
franta-hg@0: 		if isValidTypeAndURL "$vcsType" "$url"; then
franta-hg@0: 			if   [[ "$vcsType" == "hg"  ]]; then  hg clone -U     "$url" "$VCS_BACKUP_CURRENT_DIR/$d";
franta-hg@0: 			elif [[ "$vcsType" == "git" ]]; then git clone --bare "$url" "$VCS_BACKUP_CURRENT_DIR/$d";
franta-hg@0: 			fi && echo "cloned" > "$VCS_BACKUP_CONFIG_DIR/$d/state.txt";
franta-hg@0: 		else
franta-hg@0: 			echo "Unsupported VCS type: '$vcsType' or URL: '$url'" >&2;
franta-hg@0: 		fi
franta-hg@3: 
franta-hg@3: 		callBackSocket="$VCS_BACKUP_CONFIG_DIR/$d/$VCS_BACKUP_CLONE_CALLBACK_SOCKET";
franta-hg@3: 		if [[ -e "$callBackSocket" ]]; then
franta-hg@3: 			echo "done" | socat -u - unix-send:"$callBackSocket";
franta-hg@3: 		fi
franta-hg@0: 	done
franta-hg@0: }
franta-hg@0: 
franta-hg@0: # --- Single entry-point: --------------------------------------------------------------------------
franta-hg@0: 
franta-hg@0: PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin";
franta-hg@0: PUBLIC_FUNCTION_PREFIX="vcs_backup_public_";
franta-hg@0: if type -t "$PUBLIC_FUNCTION_PREFIX$1" > /dev/null; then
franta-hg@0: 	"$PUBLIC_FUNCTION_PREFIX${@:1}";
franta-hg@0: else
franta-hg@0: 	echo "Unsupported sub-command: $1" >&2
franta-hg@0: 	echo "Available sub-commands:" >&2
franta-hg@0: 	declare -F | grep "$PUBLIC_FUNCTION_PREFIX" | sed "s/.*$PUBLIC_FUNCTION_PREFIX/  /g" >&2
franta-hg@0: 	exit 1;
franta-hg@0: fi