matrix-backup-borg: add ability to backup to unencrypted repositories (#1754)

* matrix-backup-borg: added option for unencrypted repo access

* matrix-backup-borg: fixed requiring password for unencrypted repos; changed variable name

* matrix-backup-borg: add unknown_unencrypted_repo_access_is_ok to config.yaml.j2

* matrix-backup-borg: cleanup comments

* matrix-backup-borg: add documentation regarding unencrypted repos

* matrix-backup-borg: add readability and ease of use to code

* matrix-backup-borg: fix wording in defaults/main.yml comment

* matrix-backup-borg: add quotes to docs

* Indicate the variable to use

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

roles/matrix-backup-borg/defaults/main.yml

@@ -44,12 +44,15 @@ matrix_backup_borg_location_repositories: []
 # exclude following paths:
 matrix_backup_borg_location_exclude_patterns: []
 
-# borg encryption mode, only repokey-* is supported
+# borg encryption mode, only "repokey-*" and "none" are supported
 matrix_backup_borg_encryption: repokey-blake2
 
 # private ssh key used to connect to the borg repo
 matrix_backup_borg_ssh_key_private: ""
 
+# allow unencrypted repo access
+matrix_backup_borg_unknown_unencrypted_repo_access_is_ok: "{{ matrix_backup_borg_encryption == 'none' }}"
+
 # borg ssh command with ssh key
 matrix_backup_borg_storage_ssh_command: ssh -o "StrictHostKeyChecking accept-new" -i /etc/borgmatic.d/sshkey
 

roles/matrix-backup-borg/tasks/validate_config.yml

@@ -7,4 +7,9 @@
   with_items:
     - "matrix_backup_borg_ssh_key_private"
     - "matrix_backup_borg_location_repositories"
-    - "matrix_backup_borg_storage_encryption_passphrase"
+
+- name: Fail if encryption passphrase is undefined unless repository is unencrypted
+  fail:
+    msg: >-
+      You need to define a required passphrase using the `matrix_backup_borg_storage_encryption_passphrase` variable.
+  when: "matrix_backup_borg_storage_encryption_passphrase == '' and matrix_backup_borg_encryption != 'none'"

roles/matrix-backup-borg/templates/config.yaml.j2

@@ -11,6 +11,7 @@ storage:
   ssh_command: {{ matrix_backup_borg_storage_ssh_command|to_json }}
   archive_name_format: {{ matrix_backup_borg_storage_archive_name_format|to_json }}
   encryption_passphrase: {{ matrix_backup_borg_storage_encryption_passphrase|to_json }}
+  unknown_unencrypted_repo_access_is_ok: {{ matrix_backup_borg_unknown_unencrypted_repo_access_is_ok|to_json }}
 
 retention:
   keep_hourly: {{ matrix_backup_borg_retention_keep_hourly|to_json }}