fix slots

enrollments-events/app/events/allocate_slots.py

@@ -0,0 +1,101 @@
+from dataclasses import asdict, dataclass
+from uuid import uuid4
+
+from aws_lambda_powertools import Logger
+from aws_lambda_powertools.utilities.data_classes import (
+    EventBridgeEvent,
+    event_source,
+)
+from aws_lambda_powertools.utilities.typing import LambdaContext
+from layercake.dateutils import now
+from layercake.dynamodb import (
+    DynamoDBPersistenceLayer,
+    KeyChain,
+    KeyPair,
+    SortKey,
+    TransactKey,
+)
+
+from boto3clients import dynamodb_client
+from config import COURSE_TABLE, ENROLLMENT_TABLE, ORDER_TABLE
+
+logger = Logger(__name__)
+order_layer = DynamoDBPersistenceLayer(ORDER_TABLE, dynamodb_client)
+course_layer = DynamoDBPersistenceLayer(COURSE_TABLE, dynamodb_client)
+enrollment_layer = DynamoDBPersistenceLayer(ENROLLMENT_TABLE, dynamodb_client)
+
+
+@event_source(data_class=EventBridgeEvent)
+@logger.inject_lambda_context
+def lambda_handler(event: EventBridgeEvent, context: LambdaContext) -> bool:
+    new_image = event.detail['new_image']
+    now_ = now()
+    order_id = new_image['id']
+    order = order_layer.collection.get_items(
+        TransactKey(order_id) + SortKey('0') + SortKey('items', path_spec='items'),
+    )
+    tenant_id = order['tenant_id']
+    items = {
+        item['id']: int(item['quantity'])
+        for item in order['items']
+        # Ignore items with non-positive unit price;
+        # negative values are treated as discounts
+        if item['unit_price'] > 0
+    }
+
+    courses = _get_courses(set(items.keys()))
+    slots = tuple(course for course in courses for _ in range(items.get(course.id, 0)))
+    logger.info('Course slots generated', slots=slots)
+
+    with enrollment_layer.transact_writer() as transact:
+        for slot in slots:
+            transact.put(
+                item={
+                    'id': f'vacancies#{tenant_id}',
+                    'sk': f'{order_id}#{uuid4()}',
+                    # Post-migration: uncomment the follow lines
+                    # 'id': f'slots#org#{tenant_id}',
+                    # 'sk': f'order#{order_id}#enrollment#{uuid4()}',
+                    'course': asdict(slot),
+                    'created_at': now_,
+                },
+                cond_expr='attribute_not_exists(sk)',
+            )
+
+    return order_layer.update_item(
+        key=KeyPair(new_image['id'], new_image['sk']),
+        update_expr='SET #status = :status, updated_at = :updated_at',
+        expr_attr_names={
+            '#status': 'status',
+        },
+        expr_attr_values={
+            ':status': 'SUCCESS',
+            ':updated_at': now_,
+        },
+        cond_expr='attribute_exists(sk)',
+    )
+
+
+@dataclass(frozen=True)
+class Course:
+    id: str
+    name: str
+    time_in_days: int
+
+
+def _get_courses(ids: set) -> tuple[Course, ...]:
+    pairs = tuple(KeyPair(idx, '0') for idx in ids)
+    result = course_layer.collection.get_items(
+        KeyChain(pairs),
+        flatten_top=False,
+    )
+    courses = tuple(
+        Course(
+            id=idx,
+            name=obj['name'],
+            time_in_days=int(obj['access_period']),
+        )
+        for idx, obj in result.items()
+    )
+
+    return courses

enrollments-events/app/events/stopgap/enroll.py

@@ -24,11 +24,6 @@ logger = Logger(__name__)
 enrollment_layer = DynamoDBPersistenceLayer(ENROLLMENT_TABLE, dynamodb_client)
 
 
-class DeduplicationConflictError(Exception):
-    def __init__(self, *args):
-        super().__init__('Enrollment already exists')
-
-
 @event_source(data_class=EventBridgeEvent)
 @logger.inject_lambda_context
 def lambda_handler(event: EventBridgeEvent, context: LambdaContext) -> bool: