def test_conversion_rate_timeout(app, monkeypatch):
def mock_requests_get_method(*args, **kwargs):
raise requests.exceptions.ConnectTimeout("Connection Timeout")
with app.app_context():
monkeypatch.setattr("requests.get", mock_requests_get_method)
with pytest.raises(requests.exceptions.ConnectTimeout):
ConversionRate.get_conversion_rate("EUR", "PLN")
def test_update_conversion_rates_success(app, monkeypatch):
new_allowed_currencies = ("USD", "EUR")
expected_rates = {
"USD_USD": 1.0,
"USD_EUR": 0.84,
"EUR_USD": 1.19,
"EUR_EUR": 1.0
}
def new_get_conversion_rate(c1, c2):
return expected_rates[f"{c1}_{c2}"]
with app.app_context():
monkeypatch.setattr(
"currency_convertor.currency.models.allowed_currencies",
new_allowed_currencies,
)
monkeypatch.setattr(
"currency_convertor.currency.models.ConversionRate.get_conversion_rate",
new_get_conversion_rate,
)
res = ConversionRate.update_conversion_rates()
assert res["success"] == 1
assert res["data"] == expected_rates
# checking the database
db_res = ConversionRate.query.filter_by(from_currency="EUR",
to_currency="USD",
latest=1).first()
assert db_res.rate == Decimal(str(expected_rates["EUR_USD"]))
def init_db_command():
"""
Clear existing data and create new tables.
"""
init_db()
from currency_convertor.currency.models import ConversionRate
res = ConversionRate.update_conversion_rates()
click.echo("Result of database update:")
click.echo("-------------------------------------")
click.echo(res)
click.echo("Initialized the database.")
def test_conversion_rate_different_currencies(app, monkeypatch):
class Response:
status_code = 200
def json(self):
return {"EUR_PLN": 2.36}
def mock_requests_get_method(*args, **kwargs):
return Response()
with app.app_context():
monkeypatch.setattr("requests.get", mock_requests_get_method)
assert ConversionRate.get_conversion_rate("EUR", "PLN") == 2.36
def convert(from_currency, to_currency, amount):
"""
Main method in case of usage of conversion service.
The format is:
/convert/<string:from_currency>/<string:to_currency>/<amount>
Parameters
----------
from_currency : string
The origin currency
to_currency : string
The destination currency
amout : string
"""
# check if the amount can be converted to float
try:
float(amount)
except ValueError:
return error("The amount has to be numeric", 400)
# check if the currencies are one of the allowed
if from_currency not in allowed_currencies:
return error(
"The origin currency {} is not found! Allowed currencies: {}".
format(from_currency, ",".join(allowed_currencies)),
400,
)
if to_currency not in allowed_currencies:
return error(
"The destination currency {} is not found! Allowed currencies: {}".
format(to_currency, ",".join(allowed_currencies)),
400,
)
# checking the in-memory cache for stored values that are not expired
converted_amount = ConversionRate().convert_amount(from_currency,
to_currency, amount,
cache)
if converted_amount:
# we return the converted amount
return {
"from_currency": from_currency,
"to_currency": to_currency,
"amount": float(amount),
"converted": float(converted_amount),
}
# This error will appear in case of an empty database
return error("No exchange rate was found! Please try again later!", 500)
def test_convert_amount(app):
with app.app_context():
# case when the cache is empty; data is read from the database
converted_amount = ConversionRate().convert_amount(
"EUR", "USD", "1.234", cache)
assert Decimal("1.472755554") == converted_amount
# case when the cache is not empty; data is read from the cache
converted_amount = ConversionRate().convert_amount(
"EUR", "USD", "1.234", cache)
assert Decimal("1.472755554") == converted_amount
# case when there is no conversipon rate in the database, neither in cache; None is reaturned
ConversionRate.query.filter_by(from_currency="EUR",
to_currency="USD",
latest=1).delete()
db.session.commit()
cache.invalidate_all()
converted_amount = ConversionRate().convert_amount(
"EUR", "USD", "1.234", cache)
assert converted_amount is None
def test_update_conversion_rates_fail(app, monkeypatch):
new_allowed_currencies = ("USD", "EUR")
expected_rates = {
"USD_USD": 1.0,
"USD_EUR": 0.33,
"EUR_USD": 1.77,
"EUR_EUR": 1.0
}
def new_get_conversion_rate(c1, c2):
if not (c1 == "EUR" and c2 == "EUR"):
return expected_rates[f"{c1}_{c2}"]
else:
raise requests.exceptions.ConnectionError(
"Connection Error Mock HAHAHA")
with app.app_context():
# checking the database
db_res_before = ConversionRate.query.filter_by(from_currency="EUR",
to_currency="USD",
latest=1).first()
monkeypatch.setattr(
"currency_convertor.currency.models.allowed_currencies",
new_allowed_currencies,
)
monkeypatch.setattr(
"currency_convertor.currency.models.ConversionRate.get_conversion_rate",
new_get_conversion_rate,
)
res = ConversionRate.update_conversion_rates()
assert res["success"] == 0
assert res["data"] == {
"USD_USD": 1.0,
"USD_EUR": 0.33,
"EUR_USD": 1.77
}
assert "error" in res
# checking the database didn't change
db_res_after = ConversionRate.query.filter_by(from_currency="EUR",
to_currency="USD",
latest=1).first()
assert db_res_before.rate == db_res_after.rate
def update():
return ConversionRate.update_conversion_rates()
def test_financial_multiplication(a, b, result):
assert ConversionRate.financial_multiplication(a, b) == result
def test_no_cache_convert_amount(app):
with app.app_context():
# case when the cache is empty; data is read from the database
converted_amount = ConversionRate().convert_amount(
"EUR", "USD", "1.234")
assert Decimal("1.472755554") == converted_amount
def test_conversion_rate_equal_currencies():
res = ConversionRate.get_conversion_rate("USD", "USD")
assert res == 1.0