def __enter__(self) -> "AbstractSystemRunner":
"""
Supports running a system object directly as a context manager.
The system is run with the SingleThreadedRunner.
"""
from eventsourcing.system.runner import SingleThreadedRunner
if self.runner:
raise ProgrammingError("System is already running: {}".format(self.runner))
runner = SingleThreadedRunner(
system=self,
use_direct_query_if_available=self.use_direct_query_if_available,
)
runner.start()
self.runner = weakref.ref(runner)
return runner
class TestCargoShippingExample(TestCase):
def setUp(self) -> None:
self.runner = SingleThreadedRunner(
system=System(BookingApplication),
infrastructure_class=SQLAlchemyApplication,
setup_tables=True,
)
self.runner.start()
self.client = LocalClient(self.runner)
def tearDown(self) -> None:
self.runner.close()
def test_admin_can_book_new_cargo(self) -> None:
arrival_deadline = datetime.now() + timedelta(weeks=3)
cargo_id = self.client.book_new_cargo(
origin="NLRTM", destination="USDAL", arrival_deadline=arrival_deadline
)
cargo_details = self.client.get_cargo_details(cargo_id)
self.assertTrue(cargo_details["id"])
self.assertEqual(cargo_details["origin"], "NLRTM")
self.assertEqual(cargo_details["destination"], "USDAL")
self.client.change_destination(cargo_id, destination="AUMEL")
cargo_details = self.client.get_cargo_details(cargo_id)
self.assertEqual(cargo_details["destination"], "AUMEL")
self.assertEqual(cargo_details["arrival_deadline"], arrival_deadline)
def test_scenario_cargo_from_hongkong_to_stockholm(self) -> None:
# Test setup: A cargo should be shipped from Hongkong to Stockholm,
# and it should arrive in no more than two weeks.
origin = "HONGKONG"
destination = "STOCKHOLM"
arrival_deadline = datetime.now() + timedelta(weeks=2)
# Use case 1: booking.
# A new cargo is booked, and the unique tracking id is assigned to the cargo.
tracking_id = self.client.book_new_cargo(origin, destination, arrival_deadline)
# The tracking id can be used to lookup the cargo in the repository.
# Important: The cargo, and thus the domain model, is responsible for
# determining the status of the cargo, whether it is on the right track
# or not and so on. This is core domain logic. Tracking the cargo basically
# amounts to presenting information extracted from the cargo aggregate in a
# suitable way.
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["transport_status"], "NOT_RECEIVED")
self.assertEqual(cargo_details["routing_status"], "NOT_ROUTED")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(cargo_details["estimated_time_of_arrival"], None)
self.assertEqual(cargo_details["next_expected_activity"], None)
# Use case 2: routing.
#
# A number of possible routes for this cargo is requested and may be
# presented to the customer in some way for him/her to choose from.
# Selection could be affected by things like price and time of delivery,
# but this test simply uses an arbitrary selection to mimic that process.
routes_details = self.client.request_possible_routes_for_cargo(tracking_id)
route_details = select_preferred_itinerary(routes_details)
# The cargo is then assigned to the selected route, described by an itinerary.
self.client.assign_route(tracking_id, route_details)
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["transport_status"], "NOT_RECEIVED")
self.assertEqual(cargo_details["routing_status"], "ROUTED")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertTrue(cargo_details["estimated_time_of_arrival"])
self.assertEqual(
cargo_details["next_expected_activity"], ("RECEIVE", "HONGKONG")
)
# Use case 3: handling
# A handling event registration attempt will be formed from parsing
# the data coming in as a handling report either via the web service
# interface or as an uploaded CSV file. The handling event factory
# tries to create a HandlingEvent from the attempt, and if the factory
# decides that this is a plausible handling event, it is stored.
# If the attempt is invalid, for example if no cargo exists for the
# specfied tracking id, the attempt is rejected.
#
# Handling begins: cargo is received in Hongkong.
self.client.register_handling_event(tracking_id, None, "HONGKONG", "RECEIVE")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["transport_status"], "IN_PORT")
self.assertEqual(cargo_details["last_known_location"], "HONGKONG")
self.assertEqual(
cargo_details["next_expected_activity"], ("LOAD", "HONGKONG", "V1")
)
# Load onto voyage V1.
self.client.register_handling_event(tracking_id, "V1", "HONGKONG", "LOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], "V1")
self.assertEqual(cargo_details["last_known_location"], "HONGKONG")
self.assertEqual(cargo_details["transport_status"], "ONBOARD_CARRIER")
self.assertEqual(
cargo_details["next_expected_activity"], ("UNLOAD", "NEWYORK", "V1")
)
# Incorrectly unload in Tokyo.
self.client.register_handling_event(tracking_id, "V1", "TOKYO", "UNLOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], None)
self.assertEqual(cargo_details["last_known_location"], "TOKYO")
self.assertEqual(cargo_details["transport_status"], "IN_PORT")
self.assertEqual(cargo_details["is_misdirected"], True)
self.assertEqual(cargo_details["next_expected_activity"], None)
# Reroute.
routes_details = self.client.request_possible_routes_for_cargo(tracking_id)
route_details = select_preferred_itinerary(routes_details)
self.client.assign_route(tracking_id, route_details)
# Load in Tokyo.
self.client.register_handling_event(tracking_id, "V3", "TOKYO", "LOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], "V3")
self.assertEqual(cargo_details["last_known_location"], "TOKYO")
self.assertEqual(cargo_details["transport_status"], "ONBOARD_CARRIER")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(
cargo_details["next_expected_activity"], ("UNLOAD", "HAMBURG", "V3")
)
# Unload in Hamburg.
self.client.register_handling_event(tracking_id, "V3", "HAMBURG", "UNLOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], None)
self.assertEqual(cargo_details["last_known_location"], "HAMBURG")
self.assertEqual(cargo_details["transport_status"], "IN_PORT")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(
cargo_details["next_expected_activity"], ("LOAD", "HAMBURG", "V4")
)
# Load in Hamburg
self.client.register_handling_event(tracking_id, "V4", "HAMBURG", "LOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], "V4")
self.assertEqual(cargo_details["last_known_location"], "HAMBURG")
self.assertEqual(cargo_details["transport_status"], "ONBOARD_CARRIER")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(
cargo_details["next_expected_activity"], ("UNLOAD", "STOCKHOLM", "V4")
)
# Unload in Stockholm
self.client.register_handling_event(tracking_id, "V4", "STOCKHOLM", "UNLOAD")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], None)
self.assertEqual(cargo_details["last_known_location"], "STOCKHOLM")
self.assertEqual(cargo_details["transport_status"], "IN_PORT")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(
cargo_details["next_expected_activity"], ("CLAIM", "STOCKHOLM")
)
# Finally, cargo is claimed in Stockholm.
self.client.register_handling_event(tracking_id, None, "STOCKHOLM", "CLAIM")
cargo_details = self.client.get_cargo_details(tracking_id)
self.assertEqual(cargo_details["current_voyage_number"], None)
self.assertEqual(cargo_details["last_known_location"], "STOCKHOLM")
self.assertEqual(cargo_details["transport_status"], "CLAIMED")
self.assertEqual(cargo_details["is_misdirected"], False)
self.assertEqual(cargo_details["next_expected_activity"], None)
class TestBankAccountSystem(TestCase):
def setUp(self) -> None:
# Run the system with single threaded runner.
self.runner = SingleThreadedRunner(
BankAccountSystem(infrastructure_class=None))
self.runner.start()
self.commands: Commands = self.runner.get(Commands)
self.sagas: Sagas = self.runner.get(Sagas)
self.accounts: Accounts = self.runner.get(Accounts)
def tearDown(self) -> None:
del self.accounts
del self.sagas
del self.commands
self.runner.close()
del self.runner
def test_deposit_funds_ok(self):
# Create an account.
account_id1 = self.accounts.create_account()
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("0.00"))
# Deposit funds.
transaction_id = self.commands.deposit_funds(account_id1,
Decimal("200.00"))
# Check saga succeeded.
self.assertTrue(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertFalse(self.sagas.get_saga(transaction_id).has_errored)
self.assertFalse(self.sagas.get_saga(transaction_id).errors)
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("200.00"))
def test_deposit_funds_error_account_closed(self):
# Create an account.
account_id1 = self.accounts.create_account()
# Close account.
self.accounts.close_account(account_id1)
# Deposit funds.
transaction_id = self.commands.deposit_funds(account_id1,
Decimal("200.00"))
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
AccountClosedError({"account_id": account_id1}))
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("0.00"))
def test_withdraw_funds_ok(self):
# Create an account and deposit funds.
account_id1 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Withdraw funds.
transaction_id = self.commands.withdraw_funds(account_id1,
Decimal("50.00"))
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("150.00"))
# Check saga succeeded.
self.assertTrue(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertFalse(self.sagas.get_saga(transaction_id).has_errored)
self.assertFalse(self.sagas.get_saga(transaction_id).errors)
def test_withdraw_funds_error_insufficient_funds(self):
# Create an account and deposit funds.
account_id1 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Fail to withdraw funds - insufficient funds.
transaction_id = self.commands.withdraw_funds(account_id1,
Decimal("200.01"))
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
InsufficientFundsError({"account_id": account_id1}))
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("200.00"))
def test_withdraw_funds_error_account_closed(self):
# Create an account and deposit funds.
account_id1 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Close account.
self.accounts.close_account(account_id1)
# Fail to withdraw funds - account closed.
transaction_id = self.commands.withdraw_funds(
debit_account_id=account_id1, amount=Decimal("50.00"))
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
AccountClosedError({"account_id": account_id1}))
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("200.00"))
def test_transfer_funds_ok(self):
# Create two accounts and deposit funds.
account_id1 = self.accounts.create_account()
account_id2 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Transfer funds.
transaction_id = self.commands.transfer_funds(
debit_account_id=account_id1,
credit_account_id=account_id2,
amount=Decimal("50.00"),
)
# Check saga succeeded.
self.assertTrue(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertFalse(self.sagas.get_saga(transaction_id).has_errored)
self.assertFalse(self.sagas.get_saga(transaction_id).errors)
# Check balances.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("150.00"))
self.assertEqual(self.accounts.get_balance(account_id2),
Decimal("50.00"))
def test_transfer_funds_error_insufficient_funds(self):
# Create two accounts and deposit funds.
account_id1 = self.accounts.create_account()
account_id2 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Fail to transfer funds - insufficient funds.
transaction_id = self.commands.transfer_funds(
debit_account_id=account_id1,
credit_account_id=account_id2,
amount=Decimal("1000.00"),
)
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
InsufficientFundsError({"account_id": account_id1}))
# Check balances - should be unchanged.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("200.00"))
self.assertEqual(self.accounts.get_balance(account_id2),
Decimal("0.00"))
def test_transfer_funds_error_debit_account_closed(self):
# Create two accounts and deposit funds.
account_id1 = self.accounts.create_account()
account_id2 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Close account.
self.accounts.close_account(account_id1)
# Fail to transfer funds - account closed.
transaction_id = self.commands.transfer_funds(
debit_account_id=account_id1,
credit_account_id=account_id2,
amount=Decimal("50.00"),
)
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
AccountClosedError({"account_id": account_id1}))
# Check balances - should be unchanged.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("200.00"))
self.assertEqual(self.accounts.get_balance(account_id2),
Decimal("0.00"))
def test_transfer_funds_error_credit_account_closed(self):
# Create two accounts and deposit funds.
account_id1 = self.accounts.create_account()
account_id2 = self.accounts.create_account()
self.commands.deposit_funds(account_id2, Decimal("200.00"))
# Close account.
self.accounts.close_account(account_id1)
# Fail to transfer funds - account closed.
transaction_id = self.commands.transfer_funds(
debit_account_id=account_id2,
credit_account_id=account_id1,
amount=Decimal("50.00"),
)
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
AccountClosedError({"account_id": account_id1}))
# Check balances - should be unchanged.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("0.00"))
self.assertEqual(self.accounts.get_balance(account_id2),
Decimal("200.00"))
def test_overdraft_limit(self):
# Create an account and deposit funds.
account_id1 = self.accounts.create_account()
self.commands.deposit_funds(account_id1, Decimal("200.00"))
# Check overdraft limit.
self.assertEqual(self.accounts.get_overdraft_limit(account_id1),
Decimal("0.00"))
# Set overdraft limit.
self.accounts.set_overdraft_limit(account_id=account_id1,
overdraft_limit=Decimal("500.00"))
# Can't set negative overdraft limit.
with self.assertRaises(AssertionError):
self.accounts.set_overdraft_limit(
account_id=account_id1, overdraft_limit=Decimal("-500.00"))
# Check overdraft limit.
self.assertEqual(self.accounts.get_overdraft_limit(account_id1),
Decimal("500.00"))
# Withdraw funds.
transaction_id = self.commands.withdraw_funds(account_id1,
Decimal("500.00"))
# Check saga succeeded.
self.assertTrue(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertFalse(self.sagas.get_saga(transaction_id).has_errored)
self.assertFalse(self.sagas.get_saga(transaction_id).errors)
# Check balance - should be overdrawn.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("-300.00"))
# Fail to withdraw funds - insufficient funds.
transaction_id = self.commands.withdraw_funds(account_id1,
Decimal("200.01"))
# Check saga errored.
self.assertFalse(self.sagas.get_saga(transaction_id).has_succeeded)
self.assertTrue(self.sagas.get_saga(transaction_id).has_errored)
errors = self.sagas.get_saga(transaction_id).errors
self.assertEqual(len(errors), 1)
self.assertEqual(errors[0],
InsufficientFundsError({"account_id": account_id1}))
# Check balance.
self.assertEqual(self.accounts.get_balance(account_id1),
Decimal("-300.00"))
# Close account.
self.accounts.close_account(account_id1)
# Fail to set overdraft limit - account closed.
with self.assertRaises(AccountClosedError):
self.accounts.set_overdraft_limit(
account_id=account_id1, overdraft_limit=Decimal("5000.00"))