def test_metrics_spillover(capsys, metric, dimension, namespace, a_hundred_metrics):
my_metrics = Metrics()
my_metrics.add_namespace(**namespace)
my_metrics.add_dimension(**dimension)
for _metric in a_hundred_metrics:
my_metrics.add_metric(**_metric)
@my_metrics.log_metrics
def lambda_handler(evt, handler):
my_metrics.add_metric(**metric)
return True
lambda_handler({}, {})
output = capsys.readouterr().out.strip()
spillover_metrics, single_metric = output.split("\n")
spillover_metrics = json.loads(spillover_metrics)
single_metric = json.loads(single_metric)
expected_single_metric = serialize_single_metric(metric=metric, dimension=dimension, namespace=namespace)
expected_spillover_metrics = serialize_metrics(
metrics=a_hundred_metrics, dimensions=[dimension], namespace=namespace
)
remove_timestamp(metrics=[spillover_metrics, expected_spillover_metrics, single_metric, expected_single_metric])
assert single_metric["_aws"] == expected_single_metric["_aws"]
assert spillover_metrics["_aws"] == expected_spillover_metrics["_aws"]
def test_schema_no_metrics(dimensions, namespace):
my_metrics = Metrics()
my_metrics.add_namespace(**namespace)
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
with pytest.raises(SchemaValidationError):
my_metrics.serialize_metric_set()
def test_metrics_spillover(monkeypatch, capsys, metric, dimension, namespace,
a_hundred_metrics):
# GIVEN Metrics is initialized and we have over a hundred metrics to add
my_metrics = Metrics()
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
# WHEN we add more than 100 metrics
for _metric in a_hundred_metrics:
my_metrics.add_metric(**_metric)
# THEN it should serialize and flush all metrics at the 100th
# and clear all metrics and dimensions from memory
output = json.loads(capsys.readouterr().out.strip())
spillover_metrics = output["_aws"]["CloudWatchMetrics"][0]["Metrics"]
assert my_metrics.metric_set == {}
assert len(spillover_metrics) == 100
# GIVEN we add the 101th metric
# WHEN we already had a Metric class instance
# with an existing dimension set from the previous 100th metric batch
my_metrics.add_metric(**metric)
# THEN serializing the 101th metric should
# create a new EMF object with a single metric in it (101th)
# and contain have the same dimension we previously added
serialized_101th_metric = my_metrics.serialize_metric_set()
expected_101th_metric = serialize_single_metric(metric=metric,
dimension=dimension,
namespace=namespace)
remove_timestamp(metrics=[serialized_101th_metric, expected_101th_metric])
assert serialized_101th_metric["_aws"] == expected_101th_metric["_aws"]
def test_log_metrics_during_exception(capsys, metric, dimension, namespace):
# GIVEN Metrics is initialized
my_metrics = Metrics()
my_metrics.add_metric(**metric)
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
# WHEN log_metrics is used to serialize metrics
# but an error has been raised during handler execution
@my_metrics.log_metrics
def lambda_handler(evt, context):
raise ValueError("Bubble up")
with pytest.raises(ValueError):
lambda_handler({}, {})
output = json.loads(capsys.readouterr().out.strip())
expected = serialize_single_metric(metric=metric,
dimension=dimension,
namespace=namespace)
remove_timestamp(metrics=[output,
expected]) # Timestamp will always be different
# THEN we should log metrics and propagate the exception up
assert expected["_aws"] == output["_aws"]
def test_log_metrics(capsys, metrics, dimensions, namespace):
# GIVEN Metrics is initialized
my_metrics = Metrics()
my_metrics.add_namespace(**namespace)
for metric in metrics:
my_metrics.add_metric(**metric)
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
# WHEN we utilize log_metrics to serialize
# and flush all metrics at the end of a function execution
@my_metrics.log_metrics
def lambda_handler(evt, ctx):
return True
lambda_handler({}, {})
output = json.loads(capsys.readouterr().out.strip())
expected = serialize_metrics(metrics=metrics,
dimensions=dimensions,
namespace=namespace)
remove_timestamp(metrics=[output,
expected]) # Timestamp will always be different
# THEN we should have no exceptions
# and a valid EMF object should've been flushed correctly
assert expected["_aws"] == output["_aws"]
for dimension in dimensions:
assert dimension["name"] in output
def serialize_metrics(metrics: List[Dict], dimensions: List[Dict], namespace: Dict) -> Dict:
""" Helper function to build EMF object from a list of metrics, dimensions """
my_metrics = Metrics()
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
for metric in metrics:
my_metrics.add_metric(**metric)
if len(metrics) != 100:
return my_metrics.serialize_metric_set()
def test_schema_no_metrics(dimensions, namespace):
# GIVEN Metrics is initialized
my_metrics = Metrics()
my_metrics.add_namespace(**namespace)
# WHEN no metrics have been added
# but a namespace and dimensions only
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
# THEN it should fail validation and raise SchemaValidationError
with pytest.raises(SchemaValidationError):
my_metrics.serialize_metric_set()
def test_multiple_metrics(metrics, dimensions, namespace):
my_metrics = Metrics()
for metric in metrics:
my_metrics.add_metric(**metric)
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
output = my_metrics.serialize_metric_set()
expected = serialize_metrics(metrics=metrics, dimensions=dimensions, namespace=namespace)
remove_timestamp(metrics=[output, expected]) # Timestamp will always be different
assert expected["_aws"] == output["_aws"]
def test_log_metrics(capsys, metrics, dimensions, namespace):
my_metrics = Metrics()
my_metrics.add_namespace(**namespace)
for metric in metrics:
my_metrics.add_metric(**metric)
for dimension in dimensions:
my_metrics.add_dimension(**dimension)
@my_metrics.log_metrics
def lambda_handler(evt, handler):
return True
lambda_handler({}, {})
output = json.loads(capsys.readouterr().out.strip())
expected = serialize_metrics(metrics=metrics, dimensions=dimensions, namespace=namespace)
remove_timestamp(metrics=[output, expected]) # Timestamp will always be different
assert expected["_aws"] == output["_aws"]
def test_log_metrics_clear_metrics_after_invocation(metric, dimension,
namespace):
# GIVEN Metrics is initialized
my_metrics = Metrics()
my_metrics.add_metric(**metric)
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
# WHEN log_metrics is used to flush metrics from memory
@my_metrics.log_metrics
def lambda_handler(evt, context):
return True
lambda_handler({}, {})
# THEN metric set should be empty after function has been run
assert my_metrics.metric_set == {}
def test_log_metrics_error_propagation(capsys, metric, dimension, namespace):
# GIVEN Metrics are serialized after handler execution
# WHEN If an error occurs and metrics have been added
# THEN we should log metrics and propagate exception up
my_metrics = Metrics()
my_metrics.add_metric(**metric)
my_metrics.add_dimension(**dimension)
my_metrics.add_namespace(**namespace)
@my_metrics.log_metrics
def lambda_handler(evt, context):
raise ValueError("Bubble up")
with pytest.raises(ValueError):
lambda_handler({}, {})
output = json.loads(capsys.readouterr().out.strip())
expected = serialize_single_metric(metric=metric, dimension=dimension, namespace=namespace)
remove_timestamp(metrics=[output, expected]) # Timestamp will always be different
assert expected["_aws"] == output["_aws"]
import json
import requests
from aws_lambda_powertools.logging import logger_inject_lambda_context, logger_setup
from aws_lambda_powertools.metrics import Metrics, MetricUnit, single_metric
from aws_lambda_powertools.middleware_factory import lambda_handler_decorator
from aws_lambda_powertools.tracing import Tracer
tracer = Tracer()
logger = logger_setup()
metrics = Metrics()
_cold_start = True
metrics.add_dimension(name="operation", value="example")
@lambda_handler_decorator(trace_execution=True)
def my_middleware(handler, event, context, say_hello=False):
if say_hello:
print("========= HELLO PARAM DETECTED =========")
print("========= Logging event before Handler is called =========")
print(event)
ret = handler(event, context)
print("========= Logging response after Handler is called =========")
print(ret)
return ret
@metrics.log_metrics
from aws_lambda_powertools.metrics import Metrics, MetricUnit, single_metric
from aws_lambda_powertools.middleware_factory import lambda_handler_decorator
from aws_lambda_powertools.tracing import Tracer, aiohttp_trace_config
set_package_logger() # Enable package diagnostics (DEBUG log)
# tracer = Tracer() # patches all available modules
tracer = Tracer(patch_modules=(
"aioboto3", "boto3",
"requests")) # ~90-100ms faster in perf depending on set of libs
logger = Logger()
metrics = Metrics()
_cold_start = True
metrics.add_dimension(name="operation",
value="example") # added at cold start only
async def aioboto_task():
async with aioboto3.client("sts") as sts:
account = await sts.get_caller_identity()
return account
async def aiohttp_task():
# You have full access to all xray_recorder methods via `tracer.provider`
# these include thread-safe methods, all context managers, x-ray configuration etc.
# see https://github.com/aws/aws-xray-sdk-python/issues/164
async with tracer.provider.in_subsegment_async("## aiohttp escape hatch"):
async with aiohttp.ClientSession(
trace_configs=[aiohttp_trace_config()]) as session: