def test(self):
# Open an account.
account = BankAccount.open(
full_name="Alice",
email_address="*****@*****.**",
)
# Credit the account.
account.append_transaction(Decimal("10.00"))
account.append_transaction(Decimal("25.00"))
account.append_transaction(Decimal("30.00"))
transcoder = JSONTranscoder()
transcoder.register(UUIDAsHex())
transcoder.register(DecimalAsStr())
transcoder.register(DatetimeAsISO())
transcoder.register(EmailAddressAsStr())
snapshot_store = EventStore(
mapper=Mapper(transcoder=transcoder),
recorder=SQLiteAggregateRecorder(
SQLiteDatastore(":memory:"),
events_table_name="snapshots",
),
)
snapshot_store.recorder.create_table()
# Clear pending events.
account.collect_events()
# Take a snapshot.
snapshot = Snapshot.take(account)
self.assertNotIn("pending_events", snapshot.state)
# Store snapshot.
snapshot_store.put([snapshot])
# Get snapshot.
snapshots = snapshot_store.get(account.id, desc=True, limit=1)
snapshot = next(snapshots)
assert isinstance(snapshot, Snapshot)
# Reconstruct the bank account.
copy = snapshot.mutate()
assert isinstance(copy, BankAccount)
# Check copy has correct attribute values.
assert copy.id == account.id
assert copy.balance == Decimal("65.00")
def take_snapshot(self, aggregate_id: UUID, version: Optional[int] = None) -> None:
"""
Takes a snapshot of the recorded state of the aggregate,
and puts the snapshot in the snapshot store.
"""
if self.snapshots is None:
raise AssertionError(
"Can't take snapshot without snapshots store. Please "
"set environment variable IS_SNAPSHOTTING_ENABLED to "
"a true value (e.g. 'y')."
)
else:
aggregate = self.repository.get(aggregate_id, version)
snapshot = Snapshot.take(aggregate)
self.snapshots.put([snapshot])