Manage variables via systemd override config

See #1

README.md

@@ -1 +1,22 @@
 # Backup configuration for S551LN laptop
+
+## Install
+
+- run the command `make install` as admin
+- in the editor that opens, write the following configuration:
+  ```
+  [Service]
+  Environment=BORG_REPO=/path/to/borg/repo
+  Environment=BORG_PASSPHRASE=somEp4$sphrase
+  Environment=EXCLUDE_LIST=/path/to/exclude/list
+  ```
+
+## Uninstall
+
+`make uninstall`
+
+## Run manual backup
+
+- use `systemctl start borgbackup.service` to run a backup manually
+- use `journalctl -u borgbackup.service` to view the logs
+

borgbackup.service

@@ -3,13 +3,10 @@ Description=Borg backup
 
 [Service]
 Type=oneshot
-Environment=BORG_REPO=/mnt/data/thibaud/backups/S551LN/S551LN.borg/
 Environment=BORG_HOSTNAME_IS_UNIQUE=yes
-Environment=BORG_PASSPHRASE=***REMOVED***
-Environment=BORG_KEY_FILE=/home/thibaud/.config/borg/keys/S551LN_borg.2
 Nice=19
-ExecStart=/usr/local/bin/borg create --list --stats --filter AME --exclude-from=/mnt/data/thibaud/backups/S551LN/exclude-list-S551LN.txt ::{now} /
+ExecStart=/usr/bin/borg create --list --stats --filter AME --exclude-from=${EXCLUDE_LIST} ::{now} /
-ExecStartPost=/usr/local/bin/borg prune -v --list --keep-daily=7 --keep-weekly=4 --keep-monthly=10 --keep-within 2d --stats ::
+ExecStartPost=/usr/bin/borg prune -v --list --keep-daily=7 --keep-weekly=4 --keep-monthly=10 --keep-within 2d --stats ::
 
 [Install]
 WantedBy=multi-user.target