Database backup and restore

FROM mariadb:latest

RUN apt update
COPY mysqldump_backup.sh .

ENTRYPOINT [ "/bin/sh" ]
CMD [ "./mysqldump_backup.sh" ]

#!/bin/sh

FILENAME=$(basename $0 .sh)
BACKUP_TS=$(date +%F-%T)
ARCHIVE=${FILENAME}_${BACKUP_TS}.tar.gz
ERRFILE=${FILENAME}_${BACKUP_TS}.err
DMPFILE=${FILENAME}_${BACKUP_TS}.dmp
BACKUP_WORKDIR=/tmp
BACKUP_ARCHIVEDIR=/tmp
MARIADB_BACKUP_EXE_DIR="/usr/bin"

# cleanup old backups
removeOldBackups()
{
# remove backups older than -mmin for minutes, -mtime for days
echo "Removing old backups ..."
for i in `find $BACKUP_ARCHIVEDIR/*.tar.gz $BACKUP_ARCHIVEDIR/*.dmp $BACKUP_ARCHIVEDIR/*.err \
          2>/dev/null -type f -${BACKUP_RETENTION_INTERVAL} +${BACKUP_RETENTION_PERIOD} -ls | grep -o '\S\+$'`
do
        echo "Removing $i"
        rm $i >/dev/null 2>/dev/null
done
}

cd /

echo "Backup Started"

# call backup utility
{
"$MARIADB_BACKUP_EXE_DIR"/mysqldump --all-databases --host=$DB_HOST --port=$DB_PORT \
                                    --user=$DB_USER --password=$DB_PWD \
                                    --log-error=/tmp/$ERRFILE  > /tmp/$DMPFILE
}

# create a tar archive from the backup directory
tar cvzf $BACKUP_ARCHIVEDIR/$ARCHIVE $BACKUP_WORKDIR/$DMPFILE \
         $BACKUP_WORKDIR/$ERRFILE >/dev/null 2>/dev/null

# check for errors
if [ -s "$BACKUP_WORKDIR/$ERRFILE" ]
then
   rm $BACKUP_ARCHIVEDIR/$ARCHIVE >/dev/null 2>/dev/null
   cat $BACKUP_WORKDIR/$ERRFILE | xargs echo -e
   echo "Backup Completed With Errors"
   exit 1
else
   rm $BACKUP_WORKDIR/$DMPFILE \
      $BACKUP_WORKDIR/$ERRFILE >/dev/null 2>/dev/null
   removeOldBackups
   echo "Backup Completed Successfully"
   exit 0
fi

apiVersion: v2
name: mariadb-backup
description: A Helm chart for Kubernetes

# A chart can be either an 'application' or a 'library' chart.
#
# Application charts are a collection of templates that can be packaged into versioned archives
# to be deployed.
#
# Library charts provide useful utilities or functions for the chart developer. They're included as
# a dependency of application charts to inject those utilities and functions into the rendering
# pipeline. Library charts do not define any templates and therefore cannot be deployed.
type: application

# This is the chart version. This version number should be incremented each time you make changes
# to the chart and its templates, including the app version.
# Versions are expected to follow Semantic Versioning (https://semver.org/)
version: 0.1.0

# This is the version number of the application being deployed. This version number should be
# incremented each time you make changes to the application. Versions are not expected to
# follow Semantic Versioning. They should reflect the version the application is using.
# It is recommended to use it with quotes.
appVersion: "1.16.0"

# Default values for mariadb-backup.
# This is a YAML-formatted file.
# Declare variables to be passed into your templates.
image:
  tag: "ktimoney/mysqldump_backup"
backoffLimit: 4
schedule: "*/5 * * * *"
volumes:
  name: backup-pv
  storageClassName:
    path: /run/desktop/mnt/host/c/mariadb/backup
    accessModes: ReadWriteOnce
  capacity:
    storage: 50Mi
  persistentVolumeReclaimPolicy: Retain
  nodeAffinity:
    nodeSelectorTerms: docker-desktop
data:
  backup_retention_interval: mmin # mmin for minutes, mtime for days
  backup_retention_period: "120"
  db_host: host.docker.internal
  db_port: "3306"
  db_user: YmFja3Vw
  db_pwd: YmFja3Vw

apiVersion: v1
kind: PersistentVolume
metadata:
  name: {{ .Values.volumes.name }}
spec:
  capacity:
    storage: {{ .Values.volumes.capacity.storage }}
  volumeMode: Filesystem
  accessModes:
    - {{ .Values.volumes.storageClassName.accessModes }}
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: {{ .Values.volumes.storageClassName.path }}
  nodeAffinity:
    required:
      nodeSelectorTerms:
        - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
                - {{ .Values.volumes.nodeAffinity.nodeSelectorTerms }}

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: backup-claim
spec:
  storageClassName: local-storage
  accessModes:
    - {{ .Values.volumes.storageClassName.accessModes }}
  resources:
    requests:
      storage: {{ .Values.volumes.capacity.storage }}

apiVersion: v1
kind: ConfigMap
metadata:
  name: backup-config
  namespace: default
data:
  backup_retention_interval: {{ .Values.data.backup_retention_interval }}
  backup_retention_period: {{ .Values.data.backup_retention_period | quote }}
  db_host: {{ .Values.data.db_host }}
  db_port: {{ .Values.data.db_port | quote }}

apiVersion: v1
kind: Secret
metadata:
  name: backup-secret
type: Opaque
data:
  db_user: {{ .Values.data.db_user }}
  db_pwd: {{ .Values.data.db_pwd }}

apiVersion: batch/v1beta1
kind: CronJob
metadata:
  name: backup-cron
spec:
  schedule: {{ .Values.schedule | quote }}
  concurrencyPolicy: Forbid
  jobTemplate:
    spec:
      template:
        spec:
          volumes:
            - name: backup-volume
              persistentVolumeClaim:
                claimName: backup-claim
          containers:
          - name: mysqldump-backup
            image: {{ .Values.image.tag }}
            volumeMounts:
            - mountPath: /tmp
              name: backup-volume
            env:
            - name: DB_HOST
              valueFrom:
                configMapKeyRef:
                  name: backup-config
                  key: db_host
            - name: DB_PORT
              valueFrom:
                configMapKeyRef:
                  name: backup-config
                  key: db_port
            - name: BACKUP_RETENTION_INTERVAL
              valueFrom:
                configMapKeyRef:
                  name: backup-config
                  key: backup_retention_interval
            - name: BACKUP_RETENTION_PERIOD
              valueFrom:
                configMapKeyRef:
                  name: backup-config
                  key: backup_retention_period
            - name: DB_USER
              valueFrom:
                secretKeyRef:
                  name: backup-secret
                  key: db_user
            - name: DB_PWD
              valueFrom:
                secretKeyRef:
                  name: backup-secret
                  key: db_pwd
          restartPolicy: Never
      backoffLimit: {{ .Values.backoffLimit }}