feat(pathways): implement CatalogPathway

.importlinter

@@ -9,6 +9,7 @@ root_packages =
     openedx_learning
     openedx_content
     openedx_tagging
+    openedx_catalog
     openedx_django_lib
     openedx_core
 contract_types =
@@ -21,9 +22,9 @@ contract_types =
 name = "top-level source folders are layered correctly"
 type = layers
 layers =
-    # Learning-domain features (currently CBE; Learning Pathways to follow).
-    # May build on content, catalog and tagging. Nothing below may import it:
-    # in particular, openedx_tagging must never know that CBE exists.
+    # Learning-domain features (CBE and Pathways). May build on content, catalog and
+    # tagging. Nothing below may import it: in particular, openedx_tagging must never
+    # know that CBE exists.
     openedx_learning
 
     # Content: authoring-side models and APIs. May reference catalog models

src/openedx_catalog/admin.py

@@ -13,13 +13,16 @@
 from django.utils.html import format_html
 from django.utils.translation import gettext_lazy as _
 
-from .models import CatalogCourse, CourseRun
+from .models import CatalogCourse, CatalogPathway, CourseRun, PathwayCategory, PathwayEnrollment
 
 if TYPE_CHECKING:
 
     class CatalogCourseWithRunCount(CatalogCourse):
         run_count: int
 
+    class PathwayCategoryWithPathwayCount(PathwayCategory):
+        pathway_count: int
+
 
 class CatalogCourseAdmin(admin.ModelAdmin):
     """
@@ -110,3 +113,88 @@ def warnings(self, obj: CourseRun) -> str | None:
 
 
 admin.site.register(CourseRun, CourseRunAdmin)
+
+
+@admin.register(PathwayCategory)
+class PathwayCategoryAdmin(admin.ModelAdmin):
+    """
+    The PathwayCategory model admin.
+
+    Renaming a category changes what learners see. It does not change the authoring-side terminology, which is always
+    "Pathway".
+    """
+
+    list_display = ["title", "title_plural_display", "category_code", "pathways_summary"]
+    search_fields = ["title", "title_plural", "category_code"]
+
+    def get_readonly_fields(self, request, obj: PathwayCategory | None = None) -> tuple[str, ...]:
+        if obj:  # editing an existing object; the code is what other systems key off
+            return ("category_code",)
+        return tuple()
+
+    def get_queryset(self, request) -> QuerySet[PathwayCategoryWithPathwayCount]:
+        """Add the 'pathway_count' to the list_display queryset"""
+        qs = super().get_queryset(request)
+        qs = qs.annotate(pathway_count=Count("pathways"))
+        return qs
+
+    @admin.display(description=_("Plural"))
+    def title_plural_display(self, obj: PathwayCategory) -> str:
+        """Show the plural learners see, whether set explicitly or derived from the title."""
+        return obj.get_title_plural()
+
+    @admin.display(description=_("Pathways"), ordering="pathway_count")
+    def pathways_summary(self, obj: PathwayCategoryWithPathwayCount) -> str:
+        """Link to the catalog pathways using this category"""
+        if obj.pathway_count == 0:
+            return "-"
+        url = reverse("admin:openedx_catalog_catalogpathway_changelist") + f"?category={obj.pk}"
+        return format_html('<a href="{}">{}</a>', url, obj.pathway_count)
+
+
+@admin.register(CatalogPathway)
+class CatalogPathwayAdmin(admin.ModelAdmin):
+    """
+    The CatalogPathway model admin.
+
+    This edits only the catalog half of a Pathway. The Items a learner must complete live on the content side, in the
+    openedx_learning app, and are versioned there.
+    """
+
+    list_filter = ["org__short_name", "category"]
+    list_display = ["title", "category", "org_display", "pathway_code", "key_str", "created_date", "modified"]
+    search_fields = ["title", "pathway_code"]
+
+    def get_readonly_fields(self, request, obj: CatalogPathway | None = None) -> tuple[str, ...]:
+        if obj:  # editing an existing object
+            return ("org", "pathway_code")
+        return tuple()
+
+    @admin.display(description="Organization", ordering="org__short_name")
+    def org_display(self, obj: CatalogPathway) -> str:
+        """Display the organization, only showing the short_name if different from full name"""
+        if obj.org.name == obj.org.short_name:
+            return obj.org.short_name
+        return str(obj.org)
+
+    @admin.display(description=_("Created"), ordering="created")
+    def created_date(self, obj: CatalogPathway) -> datetime.date:
+        """Display the created date without the timestamp"""
+        return obj.created.date()
+
+
+@admin.register(PathwayEnrollment)
+class PathwayEnrollmentAdmin(admin.ModelAdmin):
+    """
+    The PathwayEnrollment model admin.
+    """
+
+    list_display = ["user", "catalog_pathway", "is_active", "created_date", "modified"]
+    list_filter = ["is_active", "catalog_pathway__category"]
+    # There may be very many users and a fair number of pathways, so don't use <select>
+    raw_id_fields = ["user", "catalog_pathway"]
+
+    @admin.display(description=_("Enrolled"), ordering="created")
+    def created_date(self, obj: PathwayEnrollment) -> datetime.date:
+        """Display the enrollment date without the timestamp"""
+        return obj.created.date()

src/openedx_catalog/api.py

@@ -25,6 +25,7 @@
 
 # Import only the public API methods denoted with __all__
 # pylint: disable=wildcard-import
-from .api_impl import *
+from .api_impl.courses import *
+from .api_impl.pathways import *
 
 # You'll also want the models from .models_api

src/openedx_catalog/api_impl/__init__.py

@@ -0,0 +1,3 @@
+"""
+Implementation of the `openedx_catalog` API. Import it from `openedx_catalog.api` instead.
+"""

src/openedx_catalog/api_impl.py → src/openedx_catalog/api_impl/courses.py

@@ -1,5 +1,5 @@
 """
-Implementation of the `openedx_catalog` API.
+Implementation of the course part of the `openedx_catalog` API: catalog courses and course runs.
 """
 
 import logging
@@ -9,7 +9,7 @@
 from organizations.api import ensure_organization  # type: ignore[import]
 from organizations.api import exceptions as org_exceptions
 
-from .models import CatalogCourse, CourseRun
+from ..models import CatalogCourse, CourseRun
 
 log = logging.getLogger(__name__)