checkpoint Proctored Exam.

lms/djangoapps/course_blocks/transformers/library_content.py

@@ -2,7 +2,6 @@
 Content Library Transformer, used to filter course structure per user.
 """
 import json
-from courseware.access import _has_access_to_course
 from courseware.models import StudentModule
 from openedx.core.lib.block_cache.transformer import BlockStructureTransformer
 from xmodule.library_content_module import LibraryContentModule
@@ -45,9 +44,6 @@ class ContentLibraryTransformer(BlockStructureTransformer):
 
         Arguments:
             block_structure (BlockStructureCollectedData)
-
-        Returns:
-            dict[UsageKey: dict]
         """
         block_structure.request_xblock_fields('mode')
         block_structure.request_xblock_fields('max_count')

lms/djangoapps/course_blocks/transformers/proctored_exams.py

+"""
+Proctored Exams Transformer
+"""
+
+from django.conf import settings
+
+from edx_proctoring.api import get_attempt_status_summary
+from edx_proctoring.models import ProctoredExamStudentAttemptStatus
+from openedx.core.lib.block_cache.transformer import BlockStructureTransformer
+
+
+class ProctoredExamTransformer(BlockStructureTransformer):
+    """
+    Proctored Exam Transformer Class
+    """
+    VERSION = 1
+
+    @classmethod
+    def collect(cls, block_structure):
+        """
+        Computes any information for each XBlock that's necessary to execute
+        this transformer's transform method.
+
+        Arguments:
+            block_structure (BlockStructureCollectedData)
+        """
+        block_structure.request_xblock_fields('is_proctored_enabled')
+        block_structure.request_xblock_fields('is_practice_exam')
+
+    def transform(self, user_info, block_structure):
+        """
+        Mutates block_structure based on the given user_info.
+        """
+        if not settings.FEATURES.get('ENABLE_PROCTORED_EXAMS', False):
+            return
+
+        for block_key in block_structure.topological_traversal(
+            predicate=lambda block_key: block_key.block_type == 'sequential'
+        ):
+            if (
+                block_structure.get_xblock_field(block_key, 'is_proctored_enabled') or
+                block_structure.get_xblock_field(block_key, 'is_practice_exam')
+            ):
+                # This section is an exam.  All of its sub-blocks should be excluded
+                # unless the user is not a verified student or has declined taking the exam.
+                user_exam_summary = get_attempt_status_summary(
+                    user_info.user.id,
+                    unicode(block_key.course_key),
+                    unicode(block_key),
+                )
+                if user_exam_summary and user_exam_summary['status'] != ProctoredExamStudentAttemptStatus.declined:
+                    for child_key in block_structure.get_children(block_key):
+                        block_structure.remove_block(child_key, keep_descendants=False)