feat: add restore functionality

README.md

@@ -1,6 +1,6 @@
 # BackupSidecar
 
-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. Optional notifications can be sent via Gotify to keep you informed of backup results.
+BackupSidecar is a lightweight backup and restore solution designed to run as a cron job in Kubernetes. It automates backups and restores using Restic and supports both directory and PostgreSQL database operations. Optional notifications can be sent via Gotify to keep you informed of operation results.
 
 ## Configuration
 
@@ -8,8 +8,9 @@ BackupSidecar is configured through environment variables. Below is a breakdown
 
 ### General Settings
 
-These variables apply to both directory and PostgreSQL backups.
+These variables apply to both backup and restore operations.
 
+- **`OPERATION_MODE`** _(optional)_ - Defines the operation type (`backup` or `restore`). Defaults to `backup`.
 - **`BACKUP_MODE`** _(optional)_ - Defines the backup type (`directory` or `postgres`). Defaults to `directory`.
 - **`RESTIC_PASSWORD`** _(required)_ - The encryption password for Restic.
 - **`RESTIC_REPOSITORY`** _(required)_ - The URI of the Restic repository (e.g., `rest:http://your-rest-server:8000/backup`).
@@ -20,23 +21,40 @@ These variables apply to both directory and PostgreSQL backups.
 - **`GOTIFYTOKEN`** _(required when ENABLE_GOTIFY=true)_ - The API token for Gotify.
 - **`GOTIFYTOPIC`** _(required when ENABLE_GOTIFY=true)_ - The topic under which backup notifications will be sent.
 
-### Directory Backup
+### Directory Operations
 
-When running in `directory` mode, the following variable must be set:
+When running in `directory` mode, the following variables must be set:
+
+**For Backup Operations:**
 
 - **`SOURCEDIR`** _(required)_ - The path of the directory to be backed up.
 
-### PostgreSQL Backup
+**For Restore Operations:**
+
+- **`RESTOREDIR`** _(required)_ - The path where files should be restored to.
+- **`RESTORE_SNAPSHOT_ID`** _(optional)_ - The specific snapshot ID to restore (defaults to `latest`).
+
+### PostgreSQL Operations
 
 For `postgres` mode, the following database-related variables are required:
 
+**Common Variables:**
+
 - **`PGHOST`** _(required)_ - The hostname of the PostgreSQL server.
-- **`PGDATABASE`** _(required)_ - The name of the database to back up.
+- **`PGDATABASE`** _(required)_ - The name of the database.
 - **`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.
+
+**Backup-Specific Variables:**
+
 - **`PG_DUMP_ARGS`** _(optional)_ - Additional flags for `pg_dump`.
 
+**Restore-Specific Variables:**
+
+- **`RESTORE_SNAPSHOT_ID`** _(optional)_ - The specific snapshot ID to restore (defaults to `latest`).
+- **`PSQL_ARGS`** _(optional)_ - Additional flags for `psql` (e.g., `--single-transaction`).
+
 ## Dependencies
 
 Ensure the following commands are available in the container:
@@ -44,10 +62,13 @@ Ensure the following commands are available in the container:
 - `restic`
 - `curl`
 - `jq`
-- `pg_dump` _(only required for `postgres` mode)_
+- `pg_dump` _(only required for PostgreSQL backup operations)_
+- `psql` _(only required for PostgreSQL restore operations)_
 
 ## Usage
 
+### Backup Operations
+
 Example Kubernetes CronJob manifest for running BackupSidecar as a cron job for directory backups in minimal configuration:
 
 ```yaml
@@ -105,19 +126,116 @@ spec:
                 claimName: source-data-pvc
 ```
 
+### Restore Operations
+
+Example Kubernetes Job manifest for running BackupSidecar to restore a directory:
+
+```yaml
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: backupsidecar-restore
+  namespace: authentik
+spec:
+  backoffLimit: 3
+  activeDeadlineSeconds: 600
+  template:
+    spec:
+      restartPolicy: OnFailure
+      containers:
+        - name: backupsidecar
+          image: backupsidecar:latest
+          env:
+            - name: OPERATION_MODE
+              value: "restore"
+            - name: BACKUP_MODE
+              value: "directory"
+            - name: RESTOREDIR
+              value: "/data/restore"
+            - name: RESTORE_SNAPSHOT_ID
+              value: "abc123def456" # optional, defaults to latest
+            - name: RESTIC_REPOSITORY
+              value: "rest:http://rest-server:8000/backup"
+            - name: RESTIC_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: backupsidecar-secret
+                  key: restic_password
+            - name: GOTIFYHOST
+              value: "http://gotify.example.com"
+            - name: GOTIFYTOKEN
+              valueFrom:
+                secretKeyRef:
+                  name: backupsidecar-secret
+                  key: gotify_token
+            - name: GOTIFYTOPIC
+              value: "Restore Notification"
+          volumeMounts:
+            - name: restore-data
+              mountPath: /data/restore
+      volumes:
+        - name: restore-data
+          persistentVolumeClaim:
+            claimName: restore-data-pvc
+```
+
+Example Kubernetes Job manifest for running BackupSidecar to restore a PostgreSQL database:
+
+```yaml
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: backupsidecar-postgres-restore
+  namespace: authentik
+spec:
+  backoffLimit: 3
+  activeDeadlineSeconds: 600
+  template:
+    spec:
+      restartPolicy: OnFailure
+      containers:
+        - name: backupsidecar
+          image: backupsidecar:latest
+          env:
+            - name: OPERATION_MODE
+              value: "restore"
+            - name: BACKUP_MODE
+              value: "postgres"
+            - name: PGHOST
+              value: "postgres.example.com"
+            - name: PGDATABASE
+              value: "mydatabase"
+            - name: PGUSER
+              value: "myuser"
+            - name: PGPASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: postgres-secret
+                  key: password
+            - name: PGPORT
+              value: "5432"
+            - name: RESTORE_SNAPSHOT_ID
+              value: "abc123def456" # optional, defaults to latest
+            - name: PSQL_ARGS
+              value: "--single-transaction" # optional
+            - name: RESTIC_REPOSITORY
+              value: "rest:http://rest-server:8000/backup"
+            - name: RESTIC_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: backupsidecar-secret
+                  key: restic_password
+            - name: GOTIFYHOST
+              value: "http://gotify.example.com"
+            - name: GOTIFYTOKEN
+              valueFrom:
+                secretKeyRef:
+                  name: backupsidecar-secret
+                  key: gotify_token
+            - name: GOTIFYTOPIC
+              value: "Database Restore Notification"
+```
+
 ## Notifications
 
 The script can send success or failure notifications via Gotify when enabled. To enable notifications, set `ENABLE_GOTIFY=true` and provide the required Gotify configuration variables (`GOTIFYHOST`, `GOTIFYTOKEN`, `GOTIFYTOPIC`). When notifications are disabled, backup status messages are still logged to the console.
-
-Example success notification:
-
-```
-Backup successful. Snapshot 56ff6a909a44e01f67d2d88f9a76aa713d437809d7ed14a2361e28893f38befb: files new: 1, files changed: 0, data added: 1019 bytes in 0.277535184 sec
-```
-
-When Gotify is disabled, you'll see a single message at startup indicating notifications are disabled, followed by normal backup status messages:
-
-```
-2024-01-15T10:30:00 - Gotify notifications disabled. Backup status will be logged to console only.
-2024-01-15T10:30:05 - Backup successful. Snapshot 56ff6a909a44e01f67d2d88f9a76aa713d437809d7ed14a2361e28893f38befb: files new: 1, files changed: 0, data added: 1019 bytes in 0.277535184 sec
-```