From 427e25f8112dd9e09b47fcabb345098a3c54562c Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Tue, 20 Mar 2018 12:28:35 +0100
Subject: [PATCH] Initial version

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 Dockerfile | 14 ++++++++++++++
 backup.sh  | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 Dockerfile
 create mode 100755 backup.sh

diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..f4dae20
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,14 @@
+FROM mariadb:10.2
+
+RUN set -ex \
+ && apt-get update \
+ && apt-get install -y --no-install-recommends percona-toolkit \
+ && apt-get clean -y \
+ && rm -rf /var/lib/apt/lists/*
+
+COPY backup.sh /usr/local/bin/
+
+VOLUME ["/data"]
+
+ENTRYPOINT ["/bin/bash"]
+CMD ["/usr/local/bin/backup.sh"]
diff --git a/backup.sh b/backup.sh
new file mode 100755
index 0000000..1b136be
--- /dev/null
+++ b/backup.sh
@@ -0,0 +1,52 @@
+#!/bin/bash
+set -euo pipefail
+
+function step() {
+	echo "[$(date +%Y-%m-%d %H:%M:%S)] $@"
+}
+
+[ -z "${MYSQL_PASSWORD:-}" ] && {
+	echo 'No $MYSQL_PASSWORD was set, aborting.'
+	exit 1
+}
+
+while [ 1 ]; do
+
+	# Remove old backups older than N days (default 2d)
+	DELETE_OLDER_THAN=${DELETE_OLDER_THAN:-2}
+
+	# This directory is exposed by the postgres image
+	TARGET_DIR=/var/lib/postgresql/data
+
+	BACKUP_DATE=$(date +%Y-%m-%d_%H-%M-%S)
+
+	# Collect databases
+	step "Starting backup..."
+	DATABASES=$(mysql \
+		-h "${MYSQL_HOST:-mariadb}" -u "${MYSQL_USER:-root}" -p${MYSQL_PASSWORD} \
+		-B --disable-column-names -e 'SHOW DATABASES' |
+		grep -vE '(information_schema|performance_schema|mysql|tmp)')
+
+	# Create backup
+	for db_name in ${DATABASES}; do
+		TARGET_FILE="${TARGET_DIR}/${BACKUP_DATE}_${dbname}.sql"
+		step "Creating backup of ${db_name} in ${TARGET_FILE}..."
+		mysqldump \
+			-h "${MYSQL_HOST:-mariadb}" -u "${MYSQL_USER:-root}" -p${MYSQL_PASSWORD} \
+			-a --database "${db_name}" | gzip >"${TARGET_FILE}"
+	done
+
+	# Dump grants
+	GRANTS_FILE="${TARGET_DIR}/${BACKUP_DATE}_grants.sql"
+	step "Creating grants backuo in ${GRANTS_FILE}..."
+	pt-show-grants -h "${MYSQL_HOST:-mariadb}" -u "${MYSQL_USER:-root}" -p "${MYSQL_PASSWORD}" >"${GRANTS_FILE}"
+
+	# Cleanup old backups
+	step "Removing old backups..."
+	find "${TARGET_DIR}" -name '*.sql.gz' -mtime "${DELETE_OLDER_THAN}" -delete
+
+	# Sleep until next full hour
+	step "I'm done, see ya next hour!"
+	sleep $((3600 - $(date +%s) % 3600))
+
+done