feat: run mypy as part of testing the codebase

Makefile

@@ -111,6 +111,9 @@ compile-requirements: ## Re-compile *.in requirements to *.txt
 upgrade: pre-requirements ## update the pip requirements files to use the latest releases satisfying our constraints
 	$(MAKE) compile-requirements COMPILE_OPTS="--upgrade"
 
+check-types: ## run static type-checking tests
+	mypy
+
 # These make targets currently only build LMS images.
 docker_build:
 	docker build . -f Dockerfile --target lms -t openedx/edx-platform

mypy.ini

@@ -0,0 +1,6 @@
+[mypy]
+follow_imports = silent
+ignore_missing_imports = True
+allow_untyped_globals = True
+exclude = tests
+files = openedx/core/djangoapps/content/learning_sequences/,openedx/core/types

openedx/core/djangoapps/content/learning_sequences/admin.py

@@ -11,6 +11,7 @@
 from opaque_keys import OpaqueKey
 import attr
 
+from openedx.core import types
 from .api import get_content_errors, get_course_outline
 from .models import CourseContext, CourseSectionSequence
 
@@ -82,33 +83,29 @@ def get_queryset(self, request):
         qs = qs.select_related('section', 'sequence')
         return qs
 
+    @types.admin_display(description="Title")
     def title(self, cs_seq):
         return cs_seq.sequence.title
-    title.short_description = "Title"
 
+    @types.admin_display(boolean=True)
     def accessible_after_due(self, cs_seq):
         return not cs_seq.inaccessible_after_due
-    accessible_after_due.boolean = True
 
+    @types.admin_display(boolean=True, description="Staff Only")
     def visible_to_staff_only(self, cs_seq):
         return not cs_seq.visible_to_staff_only
-    visible_to_staff_only.boolean = True
-    visible_to_staff_only.short_description = "Staff Only"
 
+    @types.admin_display(boolean=True, description="Timed Exam")
     def is_time_limited(self, cs_seq):
         return cs_seq.exam.is_time_limited
-    is_time_limited.boolean = True
-    is_time_limited.short_description = "Timed Exam"
 
+    @types.admin_display(boolean=True, description="Proctored Exam")
     def is_proctored_enabled(self, cs_seq):
         return cs_seq.exam.is_proctored_enabled
-    is_proctored_enabled.boolean = True
-    is_proctored_enabled.short_description = "Proctored Exam"
 
+    @types.admin_display(boolean=True, description="Practice Exam")
     def is_practice_exam(self, cs_seq):
         return cs_seq.exam.is_practice_exam
-    is_practice_exam.boolean = True
-    is_practice_exam.short_description = "Practice Exam"
 
 
 class CourseContextAdmin(admin.ModelAdmin):
@@ -199,24 +196,24 @@ def get_queryset(self, request):
         qs = qs.prefetch_related('section_sequences')
         return qs
 
+    @types.admin_display(description="Record Created")
     def created(self, course_context):
         return course_context.learning_context.created
-    created.short_description = "Record Created"
 
+    @types.admin_display(description="Record Modified")
     def modified(self, course_context):
         return course_context.learning_context.modified
-    modified.short_description = "Record Modified"
 
     def course_key(self, course_context):
         return course_context.learning_context.context_key
 
     def title(self, course_context):
         return course_context.learning_context.title
 
+    @types.admin_display(description="Published at (UTC)")
     def published_at(self, course_context):
         published_at_dt = course_context.learning_context.published_at
         return published_at_dt.strftime("%B %-d, %Y, %-I:%M %p")
-    published_at.short_description = "Published at (UTC)"
 
     def published_version(self, course_context):
         return course_context.learning_context.published_version
@@ -227,17 +224,17 @@ def _publish_report_attr(self, course_context, attr_name):
             return None
         return getattr(learning_context.publish_report, attr_name)
 
+    @types.admin_display(description="Errors")
     def num_errors(self, course_context):
         return self._publish_report_attr(course_context, 'num_errors')
-    num_errors.short_description = "Errors"
 
+    @types.admin_display(description="Sections")
     def num_sections(self, course_context):
         return self._publish_report_attr(course_context, 'num_sections')
-    num_sections.short_description = "Sections"
 
+    @types.admin_display(description="Sequences")
     def num_sequences(self, course_context):
         return self._publish_report_attr(course_context, 'num_sequences')
-    num_sequences.short_description = "Sequences"
 
     def raw_outline(self, obj):
         """

openedx/core/djangoapps/content/learning_sequences/api/outlines.py

@@ -6,15 +6,16 @@
 import logging
 from collections import defaultdict
 from datetime import datetime
-from typing import Dict, FrozenSet, Optional, List, Union
-from django.contrib.auth import get_user_model
-from django.db.models.query import QuerySet
+from typing import Dict, FrozenSet, List, Optional, Union
+
 from django.db import transaction
+from django.db.models.query import QuerySet
+from edx_django_utils.cache import TieredCache
 from edx_django_utils.monitoring import function_trace, set_custom_attribute
 from opaque_keys import OpaqueKey
-from opaque_keys.edx.locator import LibraryLocator
-from edx_django_utils.cache import TieredCache
 from opaque_keys.edx.keys import CourseKey
+from opaque_keys.edx.locator import LibraryLocator
+from openedx.core import types
 
 from ..data import (
     ContentErrorData,
@@ -25,30 +26,28 @@
     ExamData,
     UserCourseOutlineData,
     UserCourseOutlineDetailsData,
-    VisibilityData,
-
+    VisibilityData
 )
 from ..models import (
     ContentError,
+    CourseContext,
     CourseSection,
     CourseSectionSequence,
-    CourseContext,
     CourseSequenceExam,
     LearningContext,
     LearningSequence,
     PublishReport,
-    UserPartitionGroup,
+    UserPartitionGroup
 )
 from .permissions import can_see_all_content
 from .processors.content_gating import ContentGatingOutlineProcessor
+from .processors.enrollment import EnrollmentOutlineProcessor
+from .processors.enrollment_track_partition_groups import EnrollmentTrackPartitionGroupsOutlineProcessor
 from .processors.milestones import MilestonesOutlineProcessor
 from .processors.schedule import ScheduleOutlineProcessor
 from .processors.special_exams import SpecialExamsOutlineProcessor
 from .processors.visibility import VisibilityOutlineProcessor
-from .processors.enrollment import EnrollmentOutlineProcessor
-from .processors.enrollment_track_partition_groups import EnrollmentTrackPartitionGroupsOutlineProcessor
 
-User = get_user_model()
 log = logging.getLogger(__name__)
 
 # Public API...
@@ -255,7 +254,7 @@ def get_content_errors(course_key: CourseKey) -> List[ContentErrorData]:
 
 @function_trace('learning_sequences.api.get_user_course_outline')
 def get_user_course_outline(course_key: CourseKey,
-                            user: User,
+                            user: types.User,
                             at_time: datetime) -> UserCourseOutlineData:
     """
     Get an outline customized for a particular user at a particular time.
@@ -272,7 +271,7 @@ def get_user_course_outline(course_key: CourseKey,
 
 @function_trace('learning_sequences.api.get_user_course_outline_details')
 def get_user_course_outline_details(course_key: CourseKey,
-                                    user: User,
+                                    user: types.User,
                                     at_time: datetime) -> UserCourseOutlineDetailsData:
     """
     Get an outline with supplementary data like scheduling information.
@@ -299,7 +298,7 @@ def get_user_course_outline_details(course_key: CourseKey,
 
 
 def _get_user_course_outline_and_processors(course_key: CourseKey,  # lint-amnesty, pylint: disable=missing-function-docstring
-                                            user: User,
+                                            user: types.User,
                                             at_time: datetime):
     """
     Helper function that runs the outline processors.
@@ -352,7 +351,7 @@ def _get_user_course_outline_and_processors(course_key: CourseKey,  # lint-amnes
 
     # Open question: Does it make sense to remove a Section if it has no Sequences in it?
     trimmed_course_outline = full_course_outline.remove(usage_keys_to_remove)
-    accessible_sequences = set(trimmed_course_outline.sequences) - inaccessible_sequences
+    accessible_sequences = frozenset(set(trimmed_course_outline.sequences) - inaccessible_sequences)
 
     user_course_outline = UserCourseOutlineData(
         base_outline=full_course_outline,

openedx/core/djangoapps/content/learning_sequences/api/processors/base.py

@@ -5,10 +5,9 @@
 import logging
 from datetime import datetime
 
-from django.contrib.auth import get_user_model
 from opaque_keys.edx.keys import CourseKey  # lint-amnesty, pylint: disable=unused-import
+from openedx.core import types
 
-User = get_user_model()
 log = logging.getLogger(__name__)
 
 
@@ -33,7 +32,8 @@ class OutlineProcessor:
     additional methods to return specific metadata to feed into
     UserCourseOutlineDetailsData.
     """
-    def __init__(self, course_key: CourseKey, user: User, at_time: datetime):
+
+    def __init__(self, course_key: CourseKey, user: types.User, at_time: datetime):
         """
         Basic initialization.
 

openedx/core/djangoapps/content/learning_sequences/api/processors/content_gating.py

@@ -2,14 +2,14 @@
 import logging
 from datetime import datetime
 
-from django.contrib.auth import get_user_model
 from opaque_keys.edx.keys import CourseKey
+from openedx.core import types
+
 from common.djangoapps.student.models import EntranceExamConfiguration
 from common.djangoapps.util import milestones_helpers
 
 from .base import OutlineProcessor
 
-User = get_user_model()
 log = logging.getLogger(__name__)
 
 
@@ -21,7 +21,8 @@ class ContentGatingOutlineProcessor(OutlineProcessor):
     - Entrance Exams
     - Chapter gated content
     """
-    def __init__(self, course_key: CourseKey, user: User, at_time: datetime):
+
+    def __init__(self, course_key: CourseKey, user: types.User, at_time: datetime):
         super().__init__(course_key, user, at_time)
         self.required_content = None
         self.can_skip_entrance_exam = False

openedx/core/djangoapps/content/learning_sequences/api/processors/schedule.py

@@ -2,17 +2,18 @@
 import logging
 from collections import defaultdict  # lint-amnesty, pylint: disable=unused-import
 from datetime import datetime, timedelta
+from typing import Dict
 
-from django.contrib.auth import get_user_model
 from edx_when.api import get_dates_for_course
 from opaque_keys.edx.keys import CourseKey  # lint-amnesty, pylint: disable=unused-import
+from openedx.core import types
+
 from common.djangoapps.student.auth import user_has_role
 from common.djangoapps.student.roles import CourseBetaTesterRole
 
 from ...data import ScheduleData, ScheduleItemData, UserCourseOutlineData
 from .base import OutlineProcessor
 
-User = get_user_model()
 log = logging.getLogger(__name__)
 
 
@@ -33,10 +34,10 @@ class ScheduleOutlineProcessor(OutlineProcessor):
     * Things that are made inaccessible after they're due.
     """
 
-    def __init__(self, course_key: CourseKey, user: User, at_time: datetime):
+    def __init__(self, course_key: CourseKey, user: types.User, at_time: datetime):
         super().__init__(course_key, user, at_time)
         self.dates = None
-        self.keys_to_schedule_fields = defaultdict(dict)
+        self.keys_to_schedule_fields: Dict[str, Dict[str, datetime]] = defaultdict(dict)
         self._course_start = None
         self._course_end = None
         self._is_beta_tester = False

openedx/core/djangoapps/content/learning_sequences/data.py

@@ -26,10 +26,9 @@
 from typing import Dict, FrozenSet, List, Optional
 
 import attr
-from django.contrib.auth import get_user_model
 from opaque_keys.edx.keys import CourseKey, UsageKey
+from openedx.core import types
 
-User = get_user_model()
 log = logging.getLogger(__name__)
 
 
@@ -211,7 +210,7 @@ def not_deprecated(self, _attribute, value):
     # derived from what you pass into `sections`. Do not set this directly.
     sequences = attr.ib(type=Dict[UsageKey, CourseLearningSequenceData], init=False)
 
-    course_visibility = attr.ib(validator=attr.validators.in_(CourseVisibility))
+    course_visibility: CourseVisibility = attr.ib(validator=attr.validators.in_(CourseVisibility))
 
     # Entrance Exam ID
     entrance_exam_id = attr.ib(type=str)
@@ -339,7 +338,7 @@ class is a pretty dumb container that doesn't understand anything about how
 
     # Django User representing who we've customized this outline for. This may
     # be the AnonymousUser.
-    user: User
+    user: types.User
 
     # UTC TZ time representing the time for which this user course outline was
     # created. It is possible to create UserCourseOutlineData for a time in the

openedx/core/djangoapps/xblock/runtime/runtime.py

@@ -373,7 +373,7 @@ class can be used with many different XBlocks, whereas each XBlock gets its
 
     def __init__(
         self,
-        handler_url,  # type: (Callable[[UsageKey, str, Union[int, ANONYMOUS_USER]], str]
+        handler_url,  # type: Callable[[UsageKey, str, Union[int, ANONYMOUS_USER]], str]
         student_data_mode,  # type: Union[STUDENT_DATA_EPHEMERAL, STUDENT_DATA_PERSISTED]
         runtime_class,  # type: XBlockRuntime
     ):

openedx/core/types/__init__.py

@@ -0,0 +1,5 @@
+"""
+Add here typing utilities API functions and classes.
+"""
+from .admin import admin_display
+from .user import User

openedx/core/types/admin.py

@@ -0,0 +1,57 @@
+"""
+Typing utilities for the admin sites.
+"""
+import warnings
+
+from typing import Any, Callable, Optional, Protocol
+
+
+class AdminMethod(Protocol):
+    """
+    Duck-type definition of a callable admin method.
+
+    See:
+    https://github.com/python/mypy/issues/2087#issuecomment-462726600
+    https://mypy.readthedocs.io/en/stable/protocols.html
+    https://www.python.org/dev/peps/pep-0544/
+    """
+
+    short_description: str
+    boolean: bool
+
+
+def _admin_display(
+    boolean: Optional[bool] = None, description: Optional[str] = None
+) -> Callable[[Any], AdminMethod]:
+    """
+    Decorator for functions that need to be annotated with attributes from AdminMethod.
+
+    This method and the above AdminMethod class will no longer be necessary in Django 3.2,
+    when `admin.display` is introduced:
+    https://docs.djangoproject.com/en/3.2/ref/contrib/admin/#django.contrib.admin.display
+    """
+
+    def decorator(func: Any) -> AdminMethod:
+        if boolean is not None:
+            func.boolean = boolean
+        if description is not None:
+            func.short_description = description
+        return func
+
+    return decorator
+
+
+try:
+    import django.contrib.admin
+
+    admin_display = django.contrib.admin.display
+    if _admin_display or AdminMethod:
+        warnings.warn(
+            (
+                "Django 3.2+ available: the _admin_display method and the AdminMethod"
+                "class should be removed from openedx.core.types"
+            ),
+            DeprecationWarning,
+        )
+except AttributeError:
+    admin_display = _admin_display