170 lines
4.6 KiB
Python
170 lines
4.6 KiB
Python
from abc import ABC
|
|
from dataclasses import dataclass
|
|
from datetime import timedelta
|
|
from enum import Enum
|
|
from typing import NotRequired, TypedDict
|
|
|
|
from layercake.dateutils import now, ttl
|
|
from layercake.dynamodb import DynamoDBPersistenceLayer
|
|
from layercake.strutils import md5_hash
|
|
|
|
from config import DEDUP_WINDOW_OFFSET_DAYS
|
|
from schemas import Enrollment
|
|
|
|
Org = TypedDict(
|
|
'Org',
|
|
{
|
|
'org_id': str,
|
|
'name': str,
|
|
},
|
|
)
|
|
|
|
DeduplicationWindow = TypedDict(
|
|
'DeduplicationWindow',
|
|
{
|
|
'offset_days': int,
|
|
},
|
|
)
|
|
|
|
Subscription = TypedDict(
|
|
'Subscription',
|
|
{
|
|
'org_id': str,
|
|
'billing_day': int,
|
|
'billing_period': NotRequired[str],
|
|
},
|
|
)
|
|
|
|
|
|
class Kind(str, Enum):
|
|
ORDER = 'ORDER'
|
|
ENROLLMENT = 'ENROLLMENT'
|
|
|
|
|
|
@dataclass(frozen=True)
|
|
class LinkedEntity(ABC):
|
|
id: str
|
|
kind: Kind
|
|
table_name: str | None = None
|
|
|
|
|
|
class DeduplicationConflictError(Exception):
|
|
def __init__(self, *args):
|
|
super().__init__('Enrollment already exists')
|
|
|
|
|
|
def enroll(
|
|
enrollment: Enrollment,
|
|
*,
|
|
org: Org | None = None,
|
|
subscription: Subscription | None = None,
|
|
linked_entities: frozenset[LinkedEntity] = frozenset(),
|
|
deduplication_window: DeduplicationWindow | None = None,
|
|
persistence_layer: DynamoDBPersistenceLayer,
|
|
) -> bool:
|
|
now_ = now()
|
|
user = enrollment.user
|
|
course = enrollment.course
|
|
lock_hash = md5_hash('%s%s' % (user.id, course.id))
|
|
access_expires_at = now_ + timedelta(days=course.access_period)
|
|
|
|
with persistence_layer.transact_writer() as transact:
|
|
transact.put(
|
|
item={
|
|
'sk': '0',
|
|
'created_at': now_,
|
|
'access_expires_at': access_expires_at,
|
|
**enrollment.model_dump(),
|
|
}
|
|
| ({'subscription_covered': True} if subscription else {})
|
|
| ({'org_id': org['org_id']} if org else {}),
|
|
)
|
|
|
|
# Relationships between this enrollment and its related entities
|
|
for entity in linked_entities:
|
|
# Parent knows the child
|
|
transact.put(
|
|
item={
|
|
'id': entity.id,
|
|
'sk': f'LINKED_ENTITIES#CHILD#ENROLLMENT#{enrollment.id}',
|
|
'created_at': now_,
|
|
},
|
|
cond_expr='attribute_not_exists(sk)',
|
|
table_name=entity.table_name,
|
|
)
|
|
|
|
# Child knows the parent
|
|
transact.put(
|
|
item={
|
|
'id': enrollment.id,
|
|
'sk': f'LINKED_ENTITIES#PARENT#{entity.kind.value}#{entity.id}',
|
|
'created_at': now_,
|
|
},
|
|
cond_expr='attribute_not_exists(sk)',
|
|
)
|
|
|
|
if org:
|
|
transact.put(
|
|
item={
|
|
'id': enrollment.id,
|
|
'sk': 'ORG',
|
|
'created_at': now_,
|
|
}
|
|
| org
|
|
)
|
|
|
|
if subscription:
|
|
transact.put(
|
|
item={
|
|
'id': enrollment.id,
|
|
'sk': 'METADATA#SUBSCRIPTION_COVERED',
|
|
'created_at': now_,
|
|
}
|
|
| subscription,
|
|
)
|
|
|
|
# Prevents the user from enrolling in the same course again until
|
|
# the deduplication window expires or is removed.
|
|
offset_days = (
|
|
int(deduplication_window['offset_days'])
|
|
if deduplication_window
|
|
else DEDUP_WINDOW_OFFSET_DAYS
|
|
)
|
|
dedup_lock_ttl = ttl(
|
|
start_dt=now_,
|
|
days=course.access_period - offset_days,
|
|
)
|
|
transact.put(
|
|
item={
|
|
'id': 'LOCK',
|
|
'sk': lock_hash,
|
|
'enrollment_id': enrollment.id,
|
|
'created_at': now_,
|
|
'ttl': dedup_lock_ttl,
|
|
},
|
|
cond_expr='attribute_not_exists(sk)',
|
|
exc_cls=DeduplicationConflictError,
|
|
)
|
|
transact.put(
|
|
item={
|
|
'id': enrollment.id,
|
|
'sk': 'LOCK',
|
|
'hash': lock_hash,
|
|
'created_at': now_,
|
|
'ttl': dedup_lock_ttl,
|
|
},
|
|
)
|
|
|
|
# The deduplication window can be recalculated based on user settings.
|
|
if deduplication_window:
|
|
transact.put(
|
|
item={
|
|
'id': enrollment.id,
|
|
'sk': 'METADATA#DEDUPLICATION_WINDOW',
|
|
'offset_days': offset_days,
|
|
'created_at': now_,
|
|
},
|
|
)
|
|
|
|
return True
|