Gitbackup export facility and minor improvements.

2026-04-12 19:15:39 +02:00
parent c6c4d2794f
commit bb796024e3
9 changed files with 572 additions and 21 deletions
@@ -0,0 +1,135 @@
+#!/bin/bash
+#
+# An optional additional backup operation designed to export a
+# Time Machine-style, git-based backup for our customers of their data
+# we manage. The script compresses the local git backup repository into
+# a tarball that can be downloaded from the web.
+#
+# This script has special naming conventions:
+# - If the script file name (without extension) ends in "_w", the script will
+#   only run on Sundays.
+# - If the script file name (without extension) ends in "_m", the script will
+#   only run on the first day of the month.
+#
+# Author: Kovács Zoltán <kovacsz@marcusconsulting.hu>
+# License: GNU/GPL v3+ (https://www.gnu.org/licenses/gpl-3.0.en.html)
+# 2026-03-03 v0.1 Initial release
+
+# Accepted environment variables and their defaults.
+#
+PAR_BASEDIR=${PAR_BASEDIR:-""}			# Service's base folder
+PAR_EXPORTDIR=${PAR_EXPORTDIR:-""}		# Absolute path to export dir
+PAR_GITDIR=${PAR_GITDIR:-""}			# Absolute path to tgz dumps
+
+# Other initialisations.
+#
+EXPORTPATH="storage/backups/export"		# Default path to export dir
+GITPATH="storage/backups/webcontent"		# Default path to git repository
+SERVICENAME="redmine"                           # The composed Redmine service
+USER=${USER:-LOGNAME}				# Fix for cron enviroment only
+YMLFILE="docker-compose.yml"
+
+# Messages.
+#
+MSG_DOCKERGRPNEED="You must be a member of the docker group."
+MSG_DOESNOTRUN="This service doesn't run."
+MSG_MISSINGDEP="Fatal: missing dependency"
+MSG_MISSINGYML="Fatal: didn't find the docker-compose.yml file"
+MSG_NOLOCATE="Cannot locate the service container."
+MSG_NONWRITE="The target directory isn't writable"
+
+# Checks the dependencies.
+#
+TR=$(which tr 2>/dev/null)
+if [ -z "$TR" ]; then echo "$MSG_MISSINGDEP tr."; exit 1 ; fi
+for item in basename cp cut date dirname docker grep hostname id readlink tar
+do
+    if [ -n "$(which $item)" ]
+    then export $(echo $item | "$TR" '[:lower:]' '[:upper:]' | "$TR" '-' '_')=$(which $item)
+    else echo "$MSG_MISSINGDEP $item." >&2; exit 1; fi
+done
+# All dependencies are available via "$THECOMMAND" (upper case) call.
+#
+# Let's find which version of docker-compose is installed.
+if [ $($DOCKER compose version 2>&1 >/dev/null; echo $?) -eq 0 ]; then
+    # We'll use v2 if it is available.
+    DOCKER_COMPOSE="$DOCKER"
+    commandstring="compose"
+else
+    # Otherwise falling back to v1.
+    DOCKER_COMPOSE="$(which docker-compose)"
+    commandstring=""
+fi
+# One of the two is mandatory.
+if [ -z "$DOCKER_COMPOSE" ];then echo "$MSG_MISSINGDEP docker-compose" >&2; exit 1; fi
+# Below docker-compose should be called as "$DOCKER_COMPOSE" $commandstring sequence.
+
+# Checks the timing conventions.
+#
+# Last two characters of the filename.
+TIMING="$("$BASENAME" "$0")"; TIMING="${TIMING%.*}"; TIMING="${TIMING:0-2}"
+# If this "_w" continues only on Sundays.
+[ "$TIMING" = "_w" ] && [[ $("$DATE" +%u) -ne 0 ]] && exit 0
+# If this "_m" continues only on the 1st day of the month.
+[ "$TIMING" = "_m" ] && [[ $("$DATE" +%d) -ne 1 ]] && exit 0
+# There is no time limit, go on.
+
+# Where I'm?
+# https://gist.github.com/TheMengzor/968e5ea87e99d9c41782
+#
+SOURCE="$0"
+while [ -h "$SOURCE" ]; do
+    # resolve $SOURCE until the file is no longer a symlink
+    SCRPATH="$( cd -P "$("$DIRNAME" "$SOURCE" )" && pwd )" #"
+    SOURCE="$("$READLINK" "$SOURCE")"
+    # if $SOURCE was a relative symlink, we need to resolve it
+    # relative to the path where the symlink file was located
+    [[ $SOURCE != /* ]] && SOURCE="$SCRPATH/$SOURCE"
+done; SCRPATH="$( cd -P "$("$DIRNAME" "$SOURCE" )" && pwd )" #"
+
+# Need to be root or a Docker manager user.
+#
+[[ "$USER" != 'root' ]] \
+&& [[ -z "$(echo "$("$ID" -Gn "$USER") " | "$GREP" ' docker ')" ]] \
+&& echo "$MSG_DOCKERGRPNEED" >&2 && exit 1 #"
+
+# Searches the base folder, containing a docker-compose.yml file.
+#
+# Called from the base folder (./)?
+BASE_DIR="$PAR_BASEDIR"
+TEST_DIR="$SCRPATH"
+[[ -z "$BASE_DIR" ]] && [[ -r "$TEST_DIR/$YMLFILE" ]] && BASE_DIR="$TEST_DIR"
+# Called from ./tools?
+TEST_DIR="$("$DIRNAME" "$TEST_DIR")"
+[[ -z "$BASE_DIR" ]] && [[ -r "$TEST_DIR/$YMLFILE" ]] && BASE_DIR="$TEST_DIR"
+# Called from ./tools/*.d?
+TEST_DIR="$("$DIRNAME" "$TEST_DIR")"
+[[ -z "$BASE_DIR" ]] && [[ -r "$TEST_DIR/$YMLFILE" ]] && BASE_DIR="$TEST_DIR"
+# On failure gives it up here.
+if [ -z "$BASE_DIR" -o ! -r "$BASE_DIR/$YMLFILE" ]; then
+    echo "$MSG_MISSINGYML" >&2; exit 1
+fi
+# Sets the absolute paths.
+EXPORTDIR="${PAR_EXPORTDIR:-$BASE_DIR/$EXPORTPATH}"
+GITDIR="${PAR_GITDIR:-$BASE_DIR/$GITPATH}"
+# Exits silently if EXPORTDIR or GITDIR isn't present.
+[[ ! -e "$EXPORTDIR" ]] && exit 0
+[[ ! -e "$GITDIR" ]] && exit 0
+# EXPORTDIR must be writable.
+[[ ! -w "$EXPORTDIR" ]] \
+&& echo "$MSG_NONWRITE: $EXPORTDIR" >&2 && exit 1
+
+# Converts the service name to an actual running container's name.
+#
+MYCONTAINER="$("$DOCKER" inspect -f '{{.Name}}' $(cd "$BASE_DIR"; "$DOCKER_COMPOSE" $commandstring ps -q "$SERVICENAME") | "$CUT" -c2-)"
+# Gives up here if failed.
+if [ -z "$MYCONTAINER" ]; then echo "$MSG_NOLOCATE" >&2; exit 1; fi
+
+# Tries the backup.
+#
+pushd "$GITDIR" > /dev/null
+    EXPORTNAME=$MYCONTAINER-git.$("$DATE" '+%Y%m%d_%H%M%S').$("$HOSTNAME")
+    "$TAR" czf "$EXPORTDIR/$EXPORTNAME.tgz" . 2>"$EXPORTDIR/$EXPORTNAME.log"
+popd > /dev/null
+
+# That's all, Folks! :)