def test_get_desired_instance_count(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
sqs_client = mock_boto3.client.return_value
sqs_client.get_queue_attributes.side_effect = [
{
'Attributes': {
'ApproximateNumberOfMessages': '400'
}
},
{
'Attributes': {
'ApproximateNumberOfMessages': '350'
}
},
]
sqs_scaler = SqsScaler(**self.input_attrs)
sqs_scaler.statsd_client = Mock()
assert sqs_scaler.get_desired_instance_count() == 2
calls = [
call("testqueue1.queue-length", 400),
call("testqueue2.queue-length", 350),
]
sqs_scaler.statsd_client.incr.assert_has_calls(calls)
def test_get_sqs_throughput_of_tasks_pulled_from_queue(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
cloudwatch_client = mock_boto3.client.return_value
cloudwatch_client.get_metric_statistics.return_value = {
'Datapoints': [
{'Sum': 1500, 'Timestamp': 111111110},
{'Sum': 1600, 'Timestamp': 111111111},
{'Sum': 5500, 'Timestamp': 111111112},
{'Sum': 5300, 'Timestamp': 111111113},
{'Sum': 2100, 'Timestamp': 111111114},
]}
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
assert sqs_scaler._get_sqs_throughput_of_tasks_pulled_from_queue('my-queue') == [1500, 1600, 5500, 5300, 2100]
cloudwatch_client.get_metric_statistics.assert_called_once_with(
Namespace='AWS/SQS',
MetricName='NumberOfMessagesReceived',
Dimensions=[
{
'Name': 'QueueName',
'Value': 'my-queue'
},
],
StartTime=datetime(2018, 3, 15, 15, 5, 0),
EndTime=datetime(2018, 3, 15, 15, 10, 0),
Period=60,
Statistics=['Sum'],
Unit='Count'
)
def test_get_throughput_returns_0_if_no_data(self, mock_boto3, mocker):
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
mocker.patch.object(sqs_scaler, '_get_sqs_throughput', return_value=[])
statsd_mock = mocker.patch.object(sqs_scaler, 'statsd_client')
assert sqs_scaler._get_throughput('my-queue') == 0
statsd_mock.gauge.assert_called_once_with('testmy-queue.queue-throughput', 0)
def test_sqs_client_initialization(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
mock_client = mock_boto3.client
sqs_scaler = SqsScaler(**self.input_attrs)
sqs_scaler.statsd_client = Mock()
assert sqs_scaler.sqs_client is None
sqs_scaler.get_desired_instance_count()
assert sqs_scaler.sqs_client == mock_client.return_value
mock_client.assert_called_with('sqs', region_name='eu-west-1')
def test_get_throughput_uses_max_value(self, mock_boto3, mocker):
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
_get_sqs_throughput_mock = mocker.patch.object(sqs_scaler, '_get_sqs_throughput', return_value=[100, 200, 50])
statsd_mock = mocker.patch.object(sqs_scaler, 'statsd_client')
assert sqs_scaler._get_throughput('my-queue') == 200
# queue prefix "test" pulled from SQS_QUEUE_PREFIX env var
statsd_mock.gauge.assert_called_once_with('testmy-queue.queue-throughput', 50)
_get_sqs_throughput_mock.assert_called_once_with('testmy-queue')
def test_get_desired_instance_count_sums_based_on_queue_length_and_throughput(self, mock_boto3, mocker):
self.input_attrs['queues'] = ['queue1', 'queue2']
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
throughput_mock = mocker.patch.object(sqs_scaler, "_get_desired_instance_count_based_on_queue_throughput")
queue_length_mock = mocker.patch.object(sqs_scaler, "_get_desired_instance_count_based_on_current_queue_length")
throughput_mock.return_value = 2
queue_length_mock.return_value = 3
assert sqs_scaler._get_desired_instance_count() == 5
throughput_mock.assert_called_once()
queue_length_mock.assert_called_once()
def test_get_desired_instance_count_based_on_queue_throughput(self, mock_boto3, mocker):
self.input_attrs['queues'] = ['queue1', 'queue2']
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
_get_throughput_mock = mocker.patch.object(sqs_scaler, '_get_throughput', side_effect=[2000, 800])
# threshold is 1000
assert sqs_scaler._get_desired_instance_count_based_on_queue_throughput() == 3
assert _get_throughput_mock.call_args_list == [
call('queue1'),
call('queue2'),
]
def test_init_sets_queue_threshold_from_allowed_queue_backlog_per_worker_if_threshold_not_set(self, mock_boto3):
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **{
'allowed_queue_backlog_per_worker': 5,
'queues': []
})
assert sqs_scaler.queue_length_threshold == 5
assert sqs_scaler.throughput_threshold == 1000
def test_client_initialization(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
mock_client = mock_boto3.client
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
sqs_scaler.statsd_client = Mock()
assert sqs_scaler.sqs_client is None
assert sqs_scaler.cloudwatch_client is None
sqs_scaler.get_desired_instance_count()
assert sqs_scaler.sqs_client == mock_client.return_value
assert sqs_scaler.cloudwatch_client == mock_client.return_value
calls = [
call('sqs', region_name='eu-west-1'),
call('cloudwatch', region_name='eu-west-1'),
]
for x in calls:
assert x in mock_client.call_args_list
def test_init_sets_throughput_threshold_from_tasks_per_worker_per_minute_if_provided(self, mock_boto3):
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **{
'threshold': 100,
'tasks_per_worker_per_minute': 5,
'queues': []
})
assert sqs_scaler.queue_length_threshold == 100
assert sqs_scaler.throughput_threshold == 5
def test_init_assigns_relevant_values(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
sqs_scaler = SqsScaler(**self.input_attrs)
assert sqs_scaler.min_instances == self.input_attrs['min_instances']
assert sqs_scaler.max_instances == self.input_attrs['max_instances']
assert sqs_scaler.threshold == self.input_attrs['threshold']
assert sqs_scaler.queues == self.input_attrs['queues']
def test_init_assigns_relevant_values(self, mock_boto3):
self.input_attrs['queues'] = ['queue1', 'queue2']
sqs_scaler = SqsScaler(app_name, min_instances, max_instances, **self.input_attrs)
assert sqs_scaler.app_name == app_name
assert sqs_scaler.min_instances == min_instances
assert sqs_scaler.max_instances == max_instances
assert sqs_scaler.queue_length_threshold == self.input_attrs['threshold']
assert sqs_scaler.throughput_threshold == 1000
assert sqs_scaler.queues == self.input_attrs['queues']
def test_init_assigns_relevant_values_non_list_queue(self, mock_boto3):
self.input_attrs['queues'] = 'queue1'
sqs_scaler = SqsScaler(app_name, min_instances, max_instances,
**self.input_attrs)
assert sqs_scaler.queues == ['queue1']