def list_user_currencies(user_id: int) -> List[UserCurrencyResponseBody]:
with create_session() as session:
user = session.query(User).get(user_id)
if not user:
abort(404)
return [
UserCurrencyResponseBody.from_orm(currency)
for currency in user.currencies
]
def list_transaction(query: TransactionListQuery) -> List[TransactionResponseBody]:
with create_session() as session:
transactions = (
session.query(Transaction)
.filter(Transaction.id > query.last_id)
.limit(current_app.config['TRANSACTIONS_PER_PAGE'])
)
return [
TransactionResponseBody.from_orm(transaction)
for transaction in transactions
]
def update_currencies() -> None:
with create_session() as session:
currencies = session.query(Currency).all()
for currency in currencies:
currency.selling_rate += randint(-10,
10) * currency.selling_rate / 100
currency.buying_rate += randint(-10,
10) * currency.buying_rate / 100
currency.updated_at = datetime.utcnow()
session.add(currency)
session.commit()
print('Currencies have been updated')
def create_transaction(body: CreateTransactionBody) -> TransactionResponseBody:
with create_session() as session:
# check if ids are valid
user: User = session.query(User).get(body.user_id)
if not user:
abort(404, 'No user with such id')
currency: Currency = session.query(Currency).get(body.currency_id)
if not currency:
abort(400, 'No currency with such id')
if currency.updated_at != body.currency_updated_at:
abort(400, 'Currency timestamp is outdated')
# get user-currency association object
uc = (
session.query(UserCurrency)
.filter(UserCurrency.currency == currency, UserCurrency.user == user)
.first()
)
if not uc:
uc = UserCurrency(user=user, currency=currency)
session.add(uc)
session.flush()
if body.type == TransactionType.BUY:
cost = currency.buying_rate * body.amount
# check if user has enough money
if cost > user.balance:
abort(400, 'Not enough money')
# update balance
uc.amount += body.amount
user.balance -= cost
else: # SELL
profit = currency.selling_rate * body.amount
# check if user has enough currency
if body.amount > uc.amount:
abort(400, 'Not enough currency')
# update balance
uc.amount -= body.amount
user.balance += profit
# create transaction
transaction = Transaction(
amount=body.amount, user=user, currency=currency, type=body.type
)
session.add_all([uc, user, transaction])
session.flush()
return TransactionResponseBody.from_orm(transaction)
def list_user_transactions(
user_id: int,
query: TransactionListQuery) -> List[TransactionResponseBody]:
with create_session() as session:
user = session.query(User).get(user_id)
if not user:
abort(404)
transactions = (session.query(Transaction).filter(
Transaction.user == user).filter(
Transaction.id > query.last_id).limit(
current_app.config['TRANSACTIONS_PER_PAGE']))
return [
TransactionResponseBody.from_orm(transaction)
for transaction in transactions
]
def get_user_currency(user_id: int,
currency_id: int) -> UserCurrencyResponseBody:
with create_session() as session:
user = session.query(User).get(user_id)
if not user:
abort(404)
currency = session.query(Currency).get(currency_id)
if not currency:
abort(404)
uc = (session.query(UserCurrency).filter(
UserCurrency.currency == currency,
UserCurrency.user == user).first())
if uc:
return UserCurrencyResponseBody.from_orm(uc)
return UserCurrencyResponseBody(currency_id=currency_id)
def fill_database() -> None:
with create_session() as session:
user1 = User(balance=Decimal('5435.29'))
user2 = User(balance=Decimal('1000.00'))
currency1 = Currency(
name='Bitcoin',
selling_rate=Decimal('504.54'),
buying_rate=Decimal('632.53'),
)
currency2 = Currency(
name='Ethereum',
selling_rate=Decimal('243.10'),
buying_rate=Decimal('323.84'),
)
currency3 = Currency(
name='Dogecoin',
selling_rate=Decimal('653.09'),
buying_rate=Decimal('542.43'),
)
currency4 = Currency(
name='Litecoin',
selling_rate=Decimal('103.16'),
buying_rate=Decimal('134.64'),
)
currency5 = Currency(name='Ripple',
selling_rate=Decimal('375.28'),
buying_rate=Decimal('465.19'))
user1_currency1 = UserCurrency(user=user1,
currency=currency1,
amount=Decimal('10.58'))
user2_currency2 = UserCurrency(user=user2,
currency=currency2,
amount=Decimal('20.36'))
session.add_all([
user1,
user2,
currency1,
currency2,
currency3,
currency4,
currency5,
user1_currency1,
user2_currency2,
])
session.flush()
def list_currencies() -> List[CurrencyResponseBody]:
with create_session() as session:
currencies = session.query(Currency).all()
return [
CurrencyResponseBody.from_orm(currency) for currency in currencies
]
def create_currency(body: CurrencyRequestBody) -> CurrencyResponseBody:
with create_session() as session:
currency = Currency(**body.dict())
session.add(currency)
session.flush()
return CurrencyResponseBody.from_orm(currency)
def get_currency(currency_id: int) -> CurrencyResponseBody:
with create_session() as session:
currency = session.query(Currency).get(currency_id)
if not currency:
abort(404)
return CurrencyResponseBody.from_orm(currency)
def get_transaction(transaction_id: int) -> TransactionResponseBody:
with create_session() as session:
transaction = session.query(Transaction).get(transaction_id)
if not transaction:
abort(404)
return TransactionResponseBody.from_orm(transaction)
def list_users() -> List[UserResponseBody]:
with create_session() as session:
users = session.query(User).all()
return [UserResponseBody.from_orm(user) for user in users]
def create_user() -> UserResponseBody:
with create_session() as session:
user = User()
session.add(user)
session.flush()
return UserResponseBody.from_orm(user)
def get_user(user_id: int) -> UserResponseBody:
with create_session() as session:
user = session.query(User).get(user_id)
if not user:
abort(404)
return UserResponseBody.from_orm(user)
def session(app):
with create_session() as session:
yield session
