commit 737e6846e54ef22d226ac0aecb5e965784bd33cb
Author: Adam Štrauch <cx@initd.cz>
Date:   Sat Oct 18 01:48:43 2025 +0200

    Initial commit

diff --git a/.gitea/workflows/main.yml b/.gitea/workflows/main.yml
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+++ b/.gitea/workflows/main.yml
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+name: Build a dev image
+
+on:
+  push:
+    branches: [ main ]
+  workflow_dispatch: {}
+
+jobs:
+  build:
+    runs-on: [dev, amd64]
+    env:
+      IMAGE: gitea.ceperka.net/rosti/database-backup
+      TAG: dev
+    steps:
+      - uses: actions/checkout@v4
+      - name: docker login
+        run: |
+          docker login gitea.ceperka.net -u "${{ secrets.REGISTRY_DEV_USERNAME }}" -p "${{ secrets.REGISTRY_DEV_PASSWORD }}"
+      - name: Build
+        run: task build IMAGE=$IMAGE TAG=$TAG
+      - name: Push
+        run: task push IMAGE=$IMAGE TAG=$TAG
diff --git a/.gitea/workflows/release.yml b/.gitea/workflows/release.yml
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+++ b/.gitea/workflows/release.yml
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+name: Release of a new version
+
+on:
+  release:
+    types: [published]
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Version to release'
+        required: true
+        default: 'latest'
+        type: string
+
+jobs:
+  build:
+    runs-on: [dev, amd64]
+    env:
+      IMAGE: harbor.rosti.cz/rosti-public/database-backup
+    steps:
+      - uses: actions/checkout@v4
+
+      # Figure out the tag
+      - name: Get git tag
+        id: get_tag
+        if: github.event_name == 'release'
+        run: echo "TAG_NAME=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
+      - name: Set version from input
+        if: github.event_name == 'workflow_dispatch'
+        run: echo "TAG_NAME=${{ github.event.inputs.version }}" >> $GITHUB_ENV
+
+      - name: docker login
+        run: |
+          docker login harbor.rosti.cz -u "${{ secrets.REGISTRY_PROD_USERNAME }}" -p "${{ secrets.REGISTRY_PROD_PASSWORD }}"
+      - name: Build
+        run: task build IMAGE=$IMAGE TAG=${{ env.TAG_NAME }}
+      - name: Tag latest
+        run: task tag-latest IMAGE=$IMAGE TAG=${{ env.TAG_NAME }}
+      - name: Push
+        run: task push IMAGE=$IMAGE TAG=${{ env.TAG_NAME }}
+      - name: Push latest
+        run: task push IMAGE=$IMAGE TAG=latest
diff --git a/Dockerfile b/Dockerfile
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+++ b/Dockerfile
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+FROM alpine:3.22
+
+RUN apk add --no-cache restic docker-cli docker-cli-compose curl
+
+COPY backup.sh /backup.sh
+RUN chmod +x /backup.sh
+
+ENTRYPOINT [ "/backup.sh" ]
diff --git a/README.md b/README.md
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--- /dev/null
+++ b/README.md
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+# Database Backup Container
+
+A lightweight Alpine-based Docker container for backing up MariaDB and PostgreSQL databases using Restic.
+
+## Overview
+
+This container automatically detects the database type (MariaDB or PostgreSQL) in a target container and creates backups using Restic. It supports backing up databases from other Docker containers by executing dump commands inside them.
+
+## Features
+
+- **Multi-database support**: Automatically detects and backs up MariaDB or PostgreSQL databases
+- **Restic integration**: Uses Restic for efficient, encrypted, and deduplicated backups
+- **Docker-in-Docker**: Can access and backup databases from other containers
+- **Lightweight**: Based on Alpine Linux for minimal footprint
+
+## Prerequisites
+
+- Docker with socket access (`/var/run/docker.sock`)
+- Target container with either MariaDB or PostgreSQL client tools
+- Restic repository (local, S3, B2, etc.)
+
+## Environment Variables
+
+### Required
+
+| Variable | Description |
+|----------|-------------|
+| `CONTAINER` | Name of the Docker container where the database is running |
+| `RESTIC_PASSWORD` | Password for the Restic repository |
+| `RESTIC_REPOSITORY` | Restic repository URL (e.g., `s3:s3.amazonaws.com/bucket`, `/data/backups`) |
+
+### Database-specific
+
+#### For MariaDB containers:
+| Variable | Description |
+|----------|-------------|
+| `MARIADB_ROOT_PASSWORD` | Root password for MariaDB |
+
+#### For PostgreSQL containers:
+| Variable | Description |
+|----------|-------------|
+| `DB_USER` | PostgreSQL username |
+| `PGPASSWORD` | PostgreSQL password |
+| `DB_NAME` | PostgreSQL database name |
+
+## Usage
+
+### Basic Usage
+
+```bash
+docker run --rm \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  -e CONTAINER=my-mariadb-container \
+  -e RESTIC_PASSWORD=my-secret-password \
+  -e RESTIC_REPOSITORY=s3:s3.amazonaws.com/my-backup-bucket \
+  -e MARIADB_ROOT_PASSWORD=db-password \
+  gitea.ceperka.net/rosti/db-backup:latest
+```
+
+### With Docker Compose
+
+```yaml
+version: '3.8'
+
+services:
+  database:
+    image: mariadb:latest
+    environment:
+      MARIADB_ROOT_PASSWORD: secretpassword
+      MARIADB_DATABASE: myapp
+    volumes:
+      - db_data:/var/lib/mysql
+
+  backup:
+    image: gitea.ceperka.net/rosti/db-backup:latest
+    depends_on:
+      - database
+    environment:
+      CONTAINER: database
+      RESTIC_PASSWORD: my-backup-password
+      RESTIC_REPOSITORY: /backups
+      MARIADB_ROOT_PASSWORD: secretpassword
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+      - ./backups:/backups
+
+volumes:
+  db_data:
+```
+
+### Scheduled Backups with Cron
+
+To run backups on a schedule, you can use cron or a container orchestrator:
+
+```bash
+# Add to crontab for daily backups at 2 AM
+0 2 * * * docker run --rm -v /var/run/docker.sock:/var/run/docker.sock -e CONTAINER=my-db -e RESTIC_PASSWORD=pass -e RESTIC_REPOSITORY=/backups -e MARIADB_ROOT_PASSWORD=dbpass gitea.ceperka.net/rosti/db-backup:latest
+```
+
+### Kubernetes CronJob
+
+```yaml
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: database-backup
+spec:
+  schedule: "0 2 * * *"  # Daily at 2 AM
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+          - name: backup
+            image: gitea.ceperka.net/rosti/db-backup:latest
+            env:
+            - name: CONTAINER
+              value: "my-database-pod"
+            - name: RESTIC_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: backup-secrets
+                  key: restic-password
+            - name: RESTIC_REPOSITORY
+              value: "s3:s3.amazonaws.com/my-backup-bucket"
+            - name: MARIADB_ROOT_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: db-secrets
+                  key: root-password
+            volumeMounts:
+            - name: docker-sock
+              mountPath: /var/run/docker.sock
+          volumes:
+          - name: docker-sock
+            hostPath:
+              path: /var/run/docker.sock
+          restartPolicy: OnFailure
+```
+
+## Backup File Naming
+
+Backups are stored with the following naming convention:
+- MariaDB: `mariadb_[CONTAINER]_[DB_NAME].sql`
+- PostgreSQL: `pgsql_[CONTAINER]_[DB_NAME].sql`
+
+## Supported Restic Repositories
+
+This container supports all Restic repository types:
+
+- **Local**: `/path/to/backup/dir`
+- **SFTP**: `sftp:user@host:/path/to/repo`
+- **S3**: `s3:s3.amazonaws.com/bucket`
+- **Azure**: `azure:container:/path`
+- **Google Cloud**: `gs:bucket:/path`
+- **Backblaze B2**: `b2:bucket:/path`
+- **REST**: `rest:http://host:8000/repo`
+
+## Building
+
+```bash
+# Build the image
+task build
+
+# Tag as latest
+task tag-latest
+
+# Push to registry
+task push
+```
+
+Or manually:
+
+```bash
+docker build -t gitea.ceperka.net/rosti/db-backup:dev .
+```
+
+## Troubleshooting
+
+### Common Issues
+
+1. **"Docker is not available"**
+   - Ensure Docker socket is mounted: `-v /var/run/docker.sock:/var/run/docker.sock`
+   - Check Docker daemon is running
+
+2. **"Unsupported database type"**
+   - Verify the target container has `mariadb-dump` or `pg_dump` installed
+   - Check container name is correct
+
+3. **Authentication errors**
+   - Verify database credentials are correct
+   - Ensure environment variables are properly set
+
+### Debug Mode
+
+To debug issues, you can run the container interactively:
+
+```bash
+docker run -it --rm \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  --entrypoint /bin/sh \
+  gitea.ceperka.net/rosti/db-backup:latest
+```
+
+## Security Considerations
+
+- Store sensitive environment variables in secrets (Kubernetes secrets, Docker secrets, etc.)
+- Use least-privilege access for Docker socket when possible
+- Regularly rotate Restic repository passwords
+- Consider using encrypted storage for backup repositories
+
+## License
+
+This project is licensed under the MIT License.
diff --git a/Taskfile.yml b/Taskfile.yml
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+++ b/Taskfile.yml
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+# https://taskfile.dev
+
+version: '3'
+
+vars:
+  IMAGE: gitea.ceperka.net/rosti/db-backup
+  TAG: dev
+
+tasks:
+  build:
+    cmds:
+    - docker build -t {{ .IMAGE }}:{{ .TAG }} .
+  tag-latest:
+    cmds:
+    - docker tag {{ .IMAGE }}:{{ .TAG }} {{ .IMAGE }}:latest
+  push:
+    cmds:
+    - docker push {{ .IMAGE }}:{{ .TAG }}
+  testdb:
+    cmds:
+    - docker run -d --name testmariadb --env MARIADB_USER=maria --env MARIADB_PASSWORD=maria --env MARIADB_DATABASE=maria --env MARIADB_ROOT_PASSWORD=maria mariadb:latest
diff --git a/backup.sh b/backup.sh
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+++ b/backup.sh
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+#!/bin/bash
+
+# Environment variables
+#
+# CONTAINER - name of the container where the database is running
+# RESTIC_PASSWORD
+# RESTIC_REPOSITORY
+# NOTIFY_URL - optional, URL to send notification to
+
+if [ -z "$CONTAINER" ]; then
+    echo "CONTAINER environment variable is not set."
+    exit 1
+fi
+
+if [ -z "$RESTIC_PASSWORD" ]; then
+    echo "RESTIC_PASSWORD environment variable is not set."
+    exit 1
+fi
+
+if [ -z "$RESTIC_REPOSITORY" ]; then
+    echo "RESTIC_REPOSITORY environment variable is not set."
+    exit 1
+fi
+
+if [ ! `docker info` ]; then
+    echo "Docker is not available."
+    exit 1
+fi
+
+echo "Starting backup for container: $CONTAINER"
+if [ `docker exec -i $CONTAINER test -e /usr/bin/mariadb-dump && echo "yes" || echo "no"` = "yes" ]; then
+    DBTYPE="mariadb"
+    docker exec -i $CONTAINER mariadb-dump \
+        --user=root \
+        --password=$MARIADB_ROOT_PASSWORD \
+        --add-drop-trigger \
+        --add-drop-table \
+        --add-drop-database \
+        --hex-blob \
+        --compress \
+        --events \
+        --routines \
+        --single-transaction \
+        --triggers | restic backup --stdin --stdin-filename=$DBTYPE_$CONTAINER_$DB_NAME.sql
+elif [ `docker exec -i $CONTAINER test -e /usr/bin/pg_dump && echo "yes" || echo "no"` = "yes" ]; then
+    DBTYPE="pgsql"
+    docker exec -i $CONTAINER pg_dump --username=$DB_USER --password=$PGPASSWORD $DB_NAME | restic backup --stdin --stdin-filename=$DBTYPE_$CONTAINER_$DB_NAME.sql
+else
+    echo "Unsupported database type or database client not found in the container."
+    exit 1
+fi
+
+echo "Backup completed successfully."
+
+echo "Running restic forget and prune..."
+
+restic forget --prune --keep-daily 7 --keep-weekly 4
+
+if [ -n "$NOTIFY_URL" ]; then
+    curl $NOTIFY_URL
+fi