From 976516d0e1e65ee0fd48bb72223ef9efd63ccd82 Mon Sep 17 00:00:00 2001
From: Dan Helfman <witten@torsion.org>
Date: Tue, 8 Mar 2022 10:19:36 -0800
Subject: [PATCH] When loading a configuration file that is unreadable due to
 file permissions, warn instead of erroring (#444).

---
 NEWS                                  |  3 +++
 borgmatic/commands/borgmatic.py       | 14 ++++++++++++++
 tests/unit/commands/test_borgmatic.py |  9 +++++++++
 3 files changed, 26 insertions(+)

diff --git a/NEWS b/NEWS
index 611d525..0707a3c 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,8 @@
 1.5.24.dev0
  * #431: Add "working_directory" option to support source directories with relative paths.
+ * #444: When loading a configuration file that is unreadable due to file permissions, warn instead
+   of erroring. This supports running borgmatic as a non-root user with configuration in ~/.config
+   even if there is an unreadable global configuration file in /etc.
  * #486: Fix handling of "patterns_from" and "exclude_from" options to error instead of warning when
    referencing unreadable files and "create" action is run.
  * #507: Fix Borg usage error in the "compact" action when running "borgmatic --dry-run". Now, skip
diff --git a/borgmatic/commands/borgmatic.py b/borgmatic/commands/borgmatic.py
index 43ead04..7d70ea9 100644
--- a/borgmatic/commands/borgmatic.py
+++ b/borgmatic/commands/borgmatic.py
@@ -646,6 +646,20 @@ def load_configurations(config_filenames, overrides=None):
             configs[config_filename] = validate.parse_configuration(
                 config_filename, validate.schema_filename(), overrides
             )
+        except PermissionError:
+            logs.extend(
+                [
+                    logging.makeLogRecord(
+                        dict(
+                            levelno=logging.WARNING,
+                            levelname='WARNING',
+                            msg='{}: Insufficient permissions to read configuration file'.format(
+                                config_filename
+                            ),
+                        )
+                    ),
+                ]
+            )
         except (ValueError, OSError, validate.Validation_error) as error:
             logs.extend(
                 [
diff --git a/tests/unit/commands/test_borgmatic.py b/tests/unit/commands/test_borgmatic.py
index 474f517..2e0e79a 100644
--- a/tests/unit/commands/test_borgmatic.py
+++ b/tests/unit/commands/test_borgmatic.py
@@ -395,6 +395,15 @@ def test_load_configurations_collects_parsed_configurations():
     assert logs == []
 
 
+def test_load_configurations_logs_warning_for_permission_error():
+    flexmock(module.validate).should_receive('parse_configuration').and_raise(PermissionError)
+
+    configs, logs = tuple(module.load_configurations(('test.yaml',)))
+
+    assert configs == {}
+    assert {log.levelno for log in logs} == {logging.WARNING}
+
+
 def test_load_configurations_logs_critical_for_parse_error():
     flexmock(module.validate).should_receive('parse_configuration').and_raise(ValueError)