def test_get_lpa_by_sirius_uid_is_proxied_no_cache(self, mock_boto3):
test_id = '700012348745'
mock_sirius_provider = mock.MagicMock()
test_response = Response.factory(ident='700098765432',
code=200,
payload_json=json.dumps(
{'Testing': 'One'}))
mock_sirius_provider.get_lpa_by_sirius_uid.return_value = test_response
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
result = wrapper.get_lpa_by_sirius_uid(test_id)
assert isinstance(result, Response)
assert result is test_response
# Check the request was passed on to the real data provider
mock_sirius_provider.get_lpa_by_sirius_uid.assert_called_once_with(
test_id)
def test_updating_existing_cache_item(self, mock_datetime, mock_boto3):
"""
If an item is already in the cache, only metadata will be updated. i.e. not the payload.
"""
# This is used to determine the expiry timestamp DynamoDB should expect.
zeroed_timestamp = datetime.datetime.fromtimestamp(
0) # Set now().timestamp() to 0
mock_datetime.now.return_value = zeroed_timestamp
# ---
# Response the data provider will return
test_response = Response.factory(ident='700098765432',
code=200,
payload_json=json.dumps(
{'Testing': 'One'}))
mock_sirius_provider = mock.MagicMock()
mock_sirius_provider.get_lpa_by_lpa_online_tool_id.return_value = test_response
# ---
# Cache response. If the new hash matches, it'll be considered an update.
mock_boto3.resource.return_value.Table.return_value.get_item.return_value = {
'Item': {
'payload': json.dumps({'Testing': 'Two'}),
'response_hash':
test_response.response_hash, # Note we ensure the hashes match
'cached': '2019-04-17T20:08:50.349878+00:00',
'response_code': 200,
}
}
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
result = wrapper.get_lpa_by_lpa_online_tool_id(test_response.ident)
assert isinstance(result, Response)
# ---
# Expect only metadata fields.
expression_attribute_values = {
':datatime':
test_response.generated_datetime,
':expires':
math.floor((zeroed_timestamp +
CacheProviderWrapper.CACHE_TTL).timestamp()),
}
mock_boto3.resource.return_value.Table.return_value.update_item.assert_called_once_with(
Key={'id': test_response.ident},
UpdateExpression='SET cached=:datatime, expires=:expires',
ExpressionAttributeValues=expression_attribute_values)
def test_data_provider_exception_upstream_timeout_error(self, mock_boto3):
mock_sirius_provider = mock.MagicMock()
mock_sirius_provider.get_lpa_by_lpa_online_tool_id.side_effect = UpstreamTimeoutError(
)
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
with pytest.raises(UpstreamTimeoutError):
wrapper.get_lpa_by_lpa_online_tool_id('A54236784213')
def test_successful_cache_and_provider_lookup(self, mock_boto3):
mock_sirius_provider = mock.MagicMock()
test_response = Response.factory(ident='700098765432',
code=200,
payload_json=json.dumps(
{'Testing': 'One'}))
# The real provider will return a response. We should see this returned, not the cached version.
mock_sirius_provider.get_lpa_by_sirius_uid.return_value = test_response
# ---
test_id = '700012348745'
payload = {'Testing': 'Two'}
response_hash = 'xxx'
cached = '2019-04-17T20:08:50.349878+00:00'
mock_boto3.resource.return_value.Table.return_value.get_item.return_value = {
'Item': {
'payload': json.dumps(payload),
'response_hash': response_hash,
'cached': cached,
}
}
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
result = wrapper.get_lpa_by_sirius_uid(test_id)
# We should see the response that the cache returned
assert isinstance(result, Response)
# Response should match the one from the real data provider
assert result.ident == test_response.ident
assert result.payload == test_response.payload
assert result.response_hash == test_response.response_hash
assert result.generated_datetime == test_response.generated_datetime
# And not the one from the cache
assert not result.ident == test_id
assert not result.payload == payload
assert not result.response_hash == response_hash
assert not result.generated_datetime == cached
# These should have been called
mock_boto3.resource.return_value.Table.return_value.get_item.assert_called_once(
)
mock_sirius_provider.get_lpa_by_sirius_uid.assert_called_once_with(
test_id)
def test_data_provider_exception_internal_exception_error(
self, mock_boto3):
mock_sirius_provider = mock.MagicMock()
mock_sirius_provider.get_lpa_by_lpa_online_tool_id.side_effect = InternalExceptionError(
)
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
with pytest.raises(InternalExceptionError):
wrapper.get_lpa_by_lpa_online_tool_id('A54236784213')
def test_adding_new_cache_item(self, mock_datetime, mock_boto3):
"""
If an item isn't already in the cache, the whole response should be inserted.
"""
# This is used to determine the expiry timestamp DynamoDB should expect.
zeroed_timestamp = datetime.datetime.fromtimestamp(
0) # Set now().timestamp() to 0
mock_datetime.now.return_value = zeroed_timestamp
# ---
mock_sirius_provider = mock.MagicMock()
test_response = Response.factory(ident='700098765432',
code=200,
payload_json=json.dumps(
{'Testing': 'One'}))
mock_sirius_provider.get_lpa_by_lpa_online_tool_id.return_value = test_response
wrapper = CacheProviderWrapper(mock_sirius_provider)
result = wrapper.get_lpa_by_lpa_online_tool_id(test_response.ident)
assert isinstance(result, Response)
# ---
# Expect all fields.
expression_attribute_values = {
':datatime':
test_response.generated_datetime,
':expires':
math.floor((zeroed_timestamp +
CacheProviderWrapper.CACHE_TTL).timestamp()),
':code':
200,
':hash':
test_response.response_hash,
':payload':
json.dumps(test_response.payload),
}
mock_boto3.resource.return_value.Table.return_value.update_item.assert_called_once_with(
Key={'id': test_response.ident},
UpdateExpression=
'SET cached=:datatime, expires=:expires, response_code=:code, response_hash=:hash, payload=:payload',
ExpressionAttributeValues=expression_attribute_values)
def get_data_provider_with_cache(cls):
if 'DISABLE_DATA_CACHE' in os.environ and os.environ[
'DISABLE_DATA_CACHE'] == 'true':
logging.warning(
'Data caching is disabled; returning data provider without cache'
)
return cls.get_data_provider()
else:
return CacheProviderWrapper(cls.get_data_provider())
def test_failing_data_provider_successful_cache_lookup(self, mock_boto3):
mock_sirius_provider = mock.MagicMock()
# The real data provider returning none will result in the cached version returned
mock_sirius_provider.get_lpa_by_sirius_uid.return_value = None
# ---
test_id = '700012348745'
payload = {'Testing': True}
response_hash = 'xxx'
cached = '2019-04-17T20:08:50.349878+00:00'
code = 200
mock_boto3.resource.return_value.Table.return_value.get_item.return_value = {
'Item': {
'payload': json.dumps(payload),
'response_hash': response_hash,
'cached': cached,
'response_code': code,
}
}
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
result = wrapper.get_lpa_by_sirius_uid(test_id)
# We should see the response that the cache returned
assert isinstance(result, Response)
assert result.ident == test_id
assert result.payload == payload
assert result.response_hash == response_hash
assert result.generated_datetime == cached
assert result.code == code
# This should still have been called
mock_sirius_provider.get_lpa_by_sirius_uid.assert_called_once_with(
test_id)
def test_failing_data_provider_and_unsuccessful_cache_lookup(
self, mock_boto3):
"""
If neither the data provider of the cache can return a result, and exception is thrown.
Note: Even if an LPA is not found, the data provider should still return a valid result.
It returning anything other than a `Response` is an exception.
"""
mock_sirius_provider = mock.MagicMock()
# The real data provider returning none will result in the cached version returned
mock_sirius_provider.get_lpa_by_sirius_uid.return_value = None
# And the cache will also return no result
mock_boto3.resource.return_value.Table.return_value.get_item.return_value = {}
# ---
wrapper = CacheProviderWrapper(mock_sirius_provider)
# No result from the data provider, and nothing in the cache, throws an error exception.
with pytest.raises(ValueError):
wrapper.get_lpa_by_sirius_uid('700012348745')