refactor: v2 (#5)

Reviewed-on: #5
Co-authored-by: Timo Behrendt <t.behrendt@t00n.de>
Co-committed-by: Timo Behrendt <t.behrendt@t00n.de>

.drone.yaml

@@ -1,28 +0,0 @@
-kind: pipeline
-type: docker
-
-name: build-and-push-container
-
-triggers:
-  branch:
-    - main
-  event:
-    - push
-
-steps:
-  - name: build
-    image: docker:20
-    commands:
-      - docker build -t gitea.t000-n.de/t.behrendt/backupsidecar:${DRONE_COMMIT:0:8} .
-
-  - name: push
-    image: docker:20
-    settings:
-      username:
-        from_secret: REGISTRY_USERNAME
-      password:
-        from_secret: REGISTRY_PASSWORD
-      repo: gitea.t000-n.de/t.behrendt/backupsidecar
-      tags: 
-        - latest
-        - ${DRONE_COMMIT:0:8}

.gitea/workflows/cd.yaml

@@ -0,0 +1,83 @@
+name: Build and Release Docker Image
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build_amd64:
+    name: Build and Push amd64
+    runs-on: [ubuntu-latest, linux_amd64]
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to registry
+        uses: docker/login-action@v3
+        with:
+          registry: gitea.t000-n.de
+          username: ${{ secrets.REGISTRY_USERNAME }}
+          password: ${{ secrets.REGISTRY_PASSWORD }}
+
+      - name: Build Docker image for amd64
+        run: |
+          docker build \
+            --platform linux/amd64 \
+            -f Dockerfile \
+            -t gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-amd64 \
+            .
+
+      - name: Push Docker image for amd64
+        run: |
+          docker push gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-amd64
+
+  build_arm64:
+    name: Build and Push arm64
+    runs-on: [ubuntu-latest, linux_arm64]
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to registry
+        uses: docker/login-action@v3
+        with:
+          registry: gitea.t000-n.de
+          username: ${{ secrets.REGISTRY_USERNAME }}
+          password: ${{ secrets.REGISTRY_PASSWORD }}
+
+      - name: Build Docker image for arm64
+        run: |
+          docker build \
+            --platform linux/arm64 \
+            -f Dockerfile \
+            -t gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-arm64 \
+            .
+
+      - name: Push Docker image for arm64
+        run: |
+          docker push gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-arm64
+
+  manifest:
+    name: Create and Push Multi-Arch Manifest
+    needs: [build_amd64, build_arm64]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Log in to registry
+        uses: docker/login-action@v3
+        with:
+          registry: gitea.t000-n.de
+          username: ${{ secrets.REGISTRY_USERNAME }}
+          password: ${{ secrets.REGISTRY_PASSWORD }}
+
+      - name: Create and push manifest with git SHA
+        run: |
+          docker manifest create gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }} \
+            gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-amd64 \
+            gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-arm64
+          docker manifest push gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}
+
+          docker manifest create gitea.t000-n.de/t.behrendt/backupsidecar:latest \
+            gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-amd64 \
+            gitea.t000-n.de/t.behrendt/backupsidecar:${{ github.sha }}-arm64
+          docker manifest push gitea.t000-n.de/t.behrendt/backupsidecar:latest

.gitignore

@@ -1 +0,0 @@
-dockerBuildAndPush.sh

Dockerfile

@@ -1,14 +1,16 @@
-FROM alpine:3.17
+FROM alpine:3.21
 
-# Setup correct TZ
+RUN apk update && apk add --no-cache \
-RUN apk add alpine-conf
+    bash \
-RUN /sbin/setup-timezone -z UTC
+    curl \
-
+    restic \
-RUN apk add restic curl
+    postgresql-client \
+    jq
 
 WORKDIR /app
 
-COPY ./src/entry.sh /app/
+COPY src/backup.sh /app/backup.sh
-COPY ./src/backup.sh /app/
 
-CMD [ "/bin/sh", "entry.sh" ]
+RUN chmod +x /app/backup.sh
+
+ENTRYPOINT ["/app/backup.sh"]

README.md

@@ -1,20 +1,113 @@
-# backupsidecar
+# BackupSidecar
 
-Backup sidecar that automatically creates backups of one PVC and saves it to another PVC via restic
+BackupSidecar is a lightweight backup solution designed to run as a cron job in Kubernetes. It automates backups using Restic and supports both directory and PostgreSQL database backups. Notifications are sent via Gotify to keep you informed of backup results.
 
-## Function
+## Configuration
-A cronjob inside the container runs in the configured interval creating the backup and purging old backups.
-A notification is sent to gotify on completion of the backup or on error of either the backup or purge.
 
-## Environment Variables
+BackupSidecar is configured through environment variables. Below is a breakdown of the available settings.
-| ENV Variable | Required |Description| Example Value
+
-|--------------|----------|--------------|-
+### General Settings
-|INTERVAL|yes|cronjob interval string|15 14 * * *|
+
-|RESTIC_REPOSITORY|yes|path of the restic repository|/mnt/backups/gitea|
+These variables apply to both directory and PostgreSQL backups.
-|SOURCEDIR |yes|path of the path to backup|/mnt/toBackup/|
+
-|KEEPLAST|yes|number of increments to keep (keep in mind that the number of backups to keep correlates with the interval in which they are created) |10|
+- **`BACKUP_MODE`** _(optional)_ - Defines the backup type (`directory` or `postgres`). Defaults to `directory`.
-|RESTIC_PASSWORD|yes|password for the restic repository|******|
+- **`RESTIC_PASSWORD`** _(required)_ - The encryption password for Restic.
-|RUNONSTART|no|set to true to force a backup at the start of the container|true|
+- **`RESTIC_REPOSITORY`** _(required)_ - The URI of the Restic repository (e.g., `rest:http://your-rest-server:8000/backup`).
-|GOTIFYHOST|yes|URL of the gotify server (without trailing slash)|https://gotify.example.com|
+- **`RESTIC_REST_USERNAME`** _(optional)_ - The username for REST server authentication.
-|GOTIFYTOKEN|yes|gotify app token|******|
+- **`RESTIC_REST_PASSWORD`** _(optional)_ - The password for REST server authentication.
-|GOTIFYTOPIC|yes|gotify topic to include in the notification|gotify|
+- **`GOTIFYHOST`** _(required)_ - The Gotify server URL.
+- **`GOTIFYTOKEN`** _(required)_ - The API token for Gotify.
+- **`GOTIFYTOPIC`** _(required)_ - The topic under which backup notifications will be sent.
+
+### Directory Backup
+
+When running in `directory` mode, the following variable must be set:
+
+- **`SOURCEDIR`** _(required)_ - The path of the directory to be backed up.
+
+### PostgreSQL Backup
+
+For `postgres` mode, the following database-related variables are required:
+
+- **`PGHOST`** _(required)_ - The hostname of the PostgreSQL server.
+- **`PGDATABASE`** _(required)_ - The name of the database to back up.
+- **`PGUSER`** _(required)_ - The PostgreSQL username.
+- **`PGPORT`** _(optional)_ - The port for PostgreSQL (defaults to `5432`).
+- **`PGPASSWORD`** _(optional)_ - The password for authentication. Setting this prevents interactive prompts.
+- **`PG_DUMP_ARGS`** _(optional)_ - Additional flags for `pg_dump`.
+
+## Dependencies
+
+Ensure the following commands are available in the container:
+
+- `restic`
+- `curl`
+- `jq`
+- `pg_dump` _(only required for `postgres` mode)_
+
+## Usage
+
+Example Kubernetes CronJob manifest for running BackupSidecar as a cron job for directory backups in minimal configuration:
+
+```yaml
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: backupsidecar-cron
+  namespace: authentik
+spec:
+  schedule: "0 7 * * *"
+  concurrencyPolicy: Forbid
+  successfulJobsHistoryLimit: 5
+  failedJobsHistoryLimit: 3
+  jobTemplate:
+    spec:
+      backoffLimit: 3
+      activeDeadlineSeconds: 300
+      template:
+        spec:
+          restartPolicy: OnFailure
+          containers:
+            - name: backupsidecar
+              image: backupsidecar:latest
+              env:
+                - name: RESTIC_REPOSITORY
+                  value: "rest:http://rest-server:8000/backup"
+                - name: RESTIC_PASSWORD
+                  valueFrom:
+                    secretKeyRef:
+                      name: backupsidecar-secret
+                      key: restic_password
+                - name: BACKUP_MODE
+                  value: "directory" # or "postgres"
+                - name: SOURCEDIR
+                  value: "/data/source"
+                - name: GOTIFYHOST
+                  value: "http://gotify.example.com"
+                - name: GOTIFYTOKEN
+                  valueFrom:
+                    secretKeyRef:
+                      name: backupsidecar-secret
+                      key: gotify_token
+                - name: GOTIFYTOPIC
+                  value: "Backup Notification"
+              # (For PostgreSQL mode, add PGHOST, PGDATABASE, PGUSER, PGPORT, PGPASSWORD)
+              volumeMounts:
+                - name: source-data
+                  mountPath: /data/source
+          restartPolicy: OnFailure
+          volumes:
+            - name: source-data
+              persistentVolumeClaim:
+                claimName: source-data-pvc
+```
+
+## Notifications
+
+The script sends success or failure notifications via Gotify.
+
+Example success notification:
+
+```
+Backup successful. Snapshot 56ff6a909a44e01f67d2d88f9a76aa713d437809d7ed14a2361e28893f38befb: files new: 1, files changed: 0, data added: 1019 bytes in 0.277535184 sec
+```

example-deployment.yaml

@@ -1,62 +0,0 @@
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: backup-sidecar
-spec:
-  selector:
-    matchLabels:
-      app: backup-sidecar
-  template:
-    metadata:
-      labels:
-        app: backup-sidecar
-    spec:
-      containers:
-        - name: backup-sidecar
-          image: gitea.t000-n.de/t.behrendt/backupsidecar:latest
-          resources:
-            requests:
-              cpu: 128m
-              memory: 128Mi
-            limits:
-              cpu: 256m
-              memory: 1024Mi
-          volumeMounts:
-            - mountPath: /mnt/toBackup
-              name: data
-              readOnly: true
-            - mountPath: /mnt/backups/gitea
-              name: nfs-backup
-              subPath: gitea
-          env:
-            - name: INTERVAL
-              value: "15 14 * * *"
-            - name: RESTIC_REPOSITORY
-              value: /mnt/backups/gitea
-            - name: SOURCEDIR
-              value: "/mnt/toBackup/"
-            - name: KEEPLAST
-              value: "100"
-            - name: RESTIC_PASSWORD
-              valueFrom:
-                secretKeyRef:
-                  name: restic-credentials
-                  key: password
-            - name: RUNONSTART
-              value: "false"
-            - name: GOTIFYHOST
-              value: "https://<gotify-URL>"
-            - name: GOTIFYTOKEN
-              valueFrom:
-                secretKeyRef:
-                  name: gotify-credentials
-                  key: token
-            - name: GOTIFYTOPIC
-              value: "gitea"
-      volumes:
-        - name: data
-          persistentVolumeClaim:
-            claimName: data
-        - name: nfs-backup
-          persistentVolumeClaim:
-            claimName: backup-nfs

src/backup.sh

@@ -1,40 +1,188 @@
-#!/bin/sh
+#!/bin/bash
+set -euo pipefail
 
-GOTIFYURL="$GOTIFYHOST/message?token=$GOTIFYTOKEN"
+#######################################
+# Determine backup mode from the environment only.
+# Valid values: "directory" or "postgres".
+# Default to "directory" if not provided.
+#######################################
+BACKUP_MODE="${BACKUP_MODE:-directory}"
 
-echo "$(date +"%Y-%m-%dT%T") - Starting backup"
+#######################################
-
+# Check for required external commands.
-restic backup           \
+#######################################
-    --verbose		\
+REQUIRED_CMDS=(restic curl jq)
-    $SOURCEDIR
+if [ "$BACKUP_MODE" = "postgres" ]; then
-
+    REQUIRED_CMDS+=(pg_dump)
-RESTIC_BACKUP_RETURN=$?
-
-if [ $RESTIC_BACKUP_RETURN -eq 0 ]; then
-    MSG_BACKUP_SUCCESS="Backup successful"
-    echo "$(date +"%Y-%m-%dT%T") - $MSG_BACKUP_SUCCESS"
-    curl -s -X POST "$GOTIFYURL" -F "title=$GOTIFYTOPIC" -F "message=$MSG_BACKUP_SUCCESS"
-else
-    MSG_BACKUP_ERR="Backup failed with error code $RESTIC_BACKUP_RETURN"
-    echo "$(date +"%Y-%m-%dT%T") - MSG_BACKUP_ERR"
-    curl -s -X POST "$GOTIFYURL" -F "title=$GOTIFYTOPIC" -F "message=$MSG_BACKUP_ERR"
-    exit $RESTIC_BACKUP_RETURN
 fi
 
+for cmd in "${REQUIRED_CMDS[@]}"; do
+    if ! command -v "$cmd" &>/dev/null; then
+        echo "Error: Required command '$cmd' is not installed." >&2
+        exit 1
+    fi
+done
 
-MSG_PURGE_START="$(date +"%Y-%m-%dT%T") - Removing old backups"
+#######################################
-echo $MSG_PURGE_START
+# Validate common required environment variables.
+#######################################
+# Gotify notification settings.
+: "${GOTIFYHOST:?Environment variable GOTIFYHOST is not set}"
+: "${GOTIFYTOKEN:?Environment variable GOTIFYTOKEN is not set}"
+: "${GOTIFYTOPIC:?Environment variable GOTIFYTOPIC is not set}"
 
-restic forget --keep-last $KEEPLAST --prune
+# Restic encryption password.
-RESTIC_PURGE_RETURN=$?
+: "${RESTIC_PASSWORD:?Environment variable RESTIC_PASSWORD is not set}"
 
-if [ $RESTIC_PURGE_RETURN -eq 0 ]; then
+# Use the repository URI directly from the environment.
-    echo "$(date +"%Y-%m-%dT%T") - Purge successful"
+# Example: export RESTIC_REPOSITORY="rest:http://your-rest-server:8000/backup"
-else
+: "${RESTIC_REPOSITORY:?Environment variable RESTIC_REPOSITORY is not set}"
-    MSG_PURGE_ERR="Purge failed with error code $MSG_PURGE_ERR"
-    echo "$(date +"%Y-%m-%dT%T") - $MSG_PURGE_ERR"
-    curl -s -X POST "$GOTIFYURL" -F "title=$GOTIFYTOPIC" -F "message=$MSG_PURGE_ERR"
-    exit $RESTIC_PURGE_RETURN
-fi
 
-echo "$(date +"%Y-%m-%dT%T") - Going back to sleep..."
+#######################################
+# Validate mode-specific environment variables.
+#######################################
+case "$BACKUP_MODE" in
+    directory)
+        : "${SOURCEDIR:?Environment variable SOURCEDIR is not set (required for directory backup mode)}"
+        ;;
+    postgres)
+        : "${PGHOST:?Environment variable PGHOST is not set (required for PostgreSQL backup mode)}"
+        : "${PGDATABASE:?Environment variable PGDATABASE is not set (required for PostgreSQL backup mode)}"
+        : "${PGUSER:?Environment variable PGUSER is not set (required for PostgreSQL backup mode)}"
+        # Optional: default PGPORT to 5432.
+        : "${PGPORT:=5432}"
+        if [ -z "${PGPASSWORD:-}" ]; then
+            echo "Warning: Environment variable PGPASSWORD is not set. pg_dump may fail if authentication is required."
+        fi
+        ;;
+    *)
+        echo "Error: Unknown backup mode '$BACKUP_MODE'. Valid modes are 'directory' and 'postgres'." >&2
+        exit 1
+        ;;
+esac
+
+#######################################
+# Build the Gotify URL.
+#######################################
+GOTIFYURL="${GOTIFYHOST}/message?token=${GOTIFYTOKEN}"
+
+#######################################
+# Date format for logging.
+#######################################
+LOG_DATE_FORMAT="%Y-%m-%dT%T"
+
+#######################################
+# Log a message with a timestamp.
+# Arguments:
+#   Message to log.
+#######################################
+log() {
+    echo "$(date +"$LOG_DATE_FORMAT") - $*"
+}
+
+#######################################
+# Send a notification via Gotify.
+# Arguments:
+#   message: The message to send.
+#######################################
+send_notification() {
+    local message="$1"
+    if ! curl -s -X POST "$GOTIFYURL" -F "title=${GOTIFYTOPIC}" -F "message=${message}" >/dev/null; then
+        log "Warning: Failed to send notification with message: ${message}"
+    fi
+}
+
+#######################################
+# Run the backup using restic.
+# The --no-cache flag disables local caching.
+# Arguments:
+#   $1 - The source directory to back up.
+#######################################
+run_restic_backup() {
+    local source_dir="$1"
+    cd "${source_dir}"
+    log "Starting backup of '${source_dir}' to repository ${RESTIC_REPOSITORY}"
+    # Capture both stdout and stderr in a variable
+    backup_output=$(restic -r "${RESTIC_REPOSITORY}" backup --no-cache --json --verbose . 2>&1)
+    # Optionally, also print the output to the console:
+    echo "$backup_output"
+    # Parse the JSON lines output for the summary message
+    summary=$(echo "$backup_output" | jq -r 'select(.message_type=="summary") | "Snapshot " + (.snapshot_id // "none") + ": " + "files new: " + (.files_new|tostring) + ", files changed: " + (.files_changed|tostring) + ", data added: " + (.data_added|tostring) + " bytes in " + (.total_duration|tostring) + " sec"')
+    # Check exit code of restic backup (assuming restic exits non-zero on error)
+    if [ $? -eq 0 ]; then
+        msg="Backup successful. $summary"
+        log "$msg"
+        send_notification "$msg"
+    else
+        exit_code=$?
+        msg="Backup failed with error code ${exit_code}. $backup_output"
+        log "$msg"
+        send_notification "$msg"
+        exit "$exit_code"
+    fi
+}
+
+
+#######################################
+# Backup a directory (regular mode).
+#######################################
+backup_directory() {
+    run_restic_backup "${SOURCEDIR}"
+}
+
+#######################################
+# Backup a PostgreSQL database.
+# Dumps the database to a temporary directory and then backs it up.
+#######################################
+backup_postgres() {
+    log "Starting PostgreSQL backup for database '${PGDATABASE}' on host '${PGHOST}'"
+    
+    # Create a temporary directory for the database dump.
+    TEMP_BACKUP_DIR=$(mktemp -d)
+    log "Created temporary directory: ${TEMP_BACKUP_DIR}"
+
+    local dump_file="${TEMP_BACKUP_DIR}/dump.sql"
+    log "Dumping PostgreSQL database to ${dump_file}..."
+    if pg_dump -h "${PGHOST}" -p "${PGPORT}" -U "${PGUSER}" ${PG_DUMP_ARGS:-} "${PGDATABASE}" > "${dump_file}"; then
+        log "Database dump created successfully."
+    else
+        local exit_code=$?
+        local msg="PostgreSQL dump failed with error code ${exit_code}"
+        log "$msg"
+        send_notification "$msg"
+        exit "$exit_code"
+    fi
+
+    # Back up the directory containing the dump.
+    run_restic_backup "${TEMP_BACKUP_DIR}"
+}
+
+#######################################
+# Cleanup temporary resources.
+#######################################
+cleanup() {
+    if [ -n "${TEMP_BACKUP_DIR:-}" ] && [ -d "${TEMP_BACKUP_DIR}" ]; then
+        rm -rf "${TEMP_BACKUP_DIR}"
+        log "Removed temporary directory ${TEMP_BACKUP_DIR}"
+    fi
+}
+trap cleanup EXIT
+
+#######################################
+# Main routine.
+#######################################
+main() {
+    case "$BACKUP_MODE" in
+        directory)
+            backup_directory
+            ;;
+        postgres)
+            backup_postgres
+            ;;
+    esac
+}
+
+# Trap termination signals to log and exit cleanly.
+trap 'log "Script interrupted. Exiting."; exit 1' SIGINT SIGTERM
+
+main

src/entry.sh

@@ -1,18 +0,0 @@
-#!/bin/sh
-
-mkdir /etc/cron.d
-touch /etc/cron.d/backup
-echo "$INTERVAL /bin/sh /app/backup.sh" > /etc/cron.d/backup
-
-# change ownership and make the cron known to crontab
-chmod 0644 /etc/cron.d/backup && crontab /etc/cron.d/backup
-
-
-if [ $RUNONSTART = 'true' ]; then
-    echo $(date +"%Y-%m-%dT%T") "- Running initial backup"
-    /bin/sh /app/backup.sh
-fi
-
-# Wait until infinity
-echo $(date +"%Y-%m-%dT%T") "- Starting cron"
-crond -f