Add fuzzy matching mode for parent groups while searching course groups

CHANGELOG.rst

@@ -9,6 +9,12 @@ and this project adheres to `Semantic Versioning`_.
 Unreleased
 ----------
 
+Added
+~~~~~
+
+* Add fuzzy matching mode for searching course groups: If no 100 % match is found,
+  the importer will search a match by a subset of parent groups.
+
 Changed
 ~~~~~~~
 

aleksis/apps/untis/preferences.py

@@ -91,6 +91,15 @@ class UseCourseGroups(BooleanPreference):
     )
 
 
+@site_preferences_registry.register
+class CourseGroupsFuzzyMatching(BooleanPreference):
+    section = untis_mysql
+    name = "course_groups_fuzzy_matching"
+    default = False
+    verbose_name = _("Match course groups by a subset of parent groups if no 100% match is found")
+    help_text = _("Works only if 'Use course groups' is activated.")
+
+
 @site_preferences_registry.register
 class IgnoreIncompleteSubstitutions(BooleanPreference):
     section = untis_mysql

aleksis/apps/untis/util/mysql/importers/lessons.py

@@ -144,6 +144,34 @@ def import_lessons(
                             "teachers (owners) and subject"
                         )
 
+                if (
+                    not match
+                    and get_site_preferences()["untis_mysql__course_groups_fuzzy_matching"]
+                ):
+                    if qs.count() != 1:
+                        logger.warning(
+                            "    Course group not found by searching by parent groups, "
+                            "teachers (owners) and subject (fuzzy matching mode)"
+                        )
+                    else:
+                        for found_group in qs:
+                            if compare_m2m(teachers, found_group.owners.all()):
+                                if match:
+                                    logger.warning(
+                                        "    More than one course group found "
+                                        "by searching by parent groups, "
+                                        "teachers (owners) and subject (fuzzy matching mode)"
+                                    )
+                                    match = False
+                                    course_group = None
+                                else:
+                                    match = True
+                                    course_group = found_group
+                                    logger.info(
+                                        "    Course group found by searching by parent groups, "
+                                        "teachers (owners) and subject (fuzzy matching mode)"
+                                    )
+
                 changed = False
                 if not match:
                     # No matching group found