Description
Use case
Amazon CloudWatch announced support for high resolution metric extraction from structured logs (EMF). Customers can now provide an optional StorageResolution parameter within the EMF specification with a value of 1 or 60 (default) to indicate the desired resolution (in seconds) of the metric.
We should consider adding support for this new optional parameter to Metrics.
The EMF log should have this format:
{
"_aws": {
"CloudWatchMetrics": [
{
"Metrics": [
{
"Name": "Time",
"Unit": "Milliseconds",
"StorageResolution": 60 // <- new key
}
],
...
}
]
},
"Time": 1
}As part of this issue we should also update the API docs, documentation, and unit/integration tests.
Solution/User Experience
from aws_lambda_powertools import Metrics
from aws_lambda_powertools.metrics import MetricUnit, MetricResolution
from aws_lambda_powertools.utilities.typing import LambdaContext
metrics = Metrics()
@metrics.log_metrics # ensures metrics are flushed upon request completion/failure
def lambda_handler(event: dict, context: LambdaContext):
# Publish a metric with standard resolution i.e. StorageResolution = 60
metrics.add_metric(name="SuccessfulBooking", unit=MetricUnit.Count, value=1, resolution=MetricResolution.Standard)
# Publish a metric with high resolution i.e. StorageResolution = 1
metrics.add_metric(name="FailedBooking", unit=MetricUnit.Count, value=1, resolution=MetricResolution.High)
# The last parameter (storage resolution) is optional
metrics.add_metric(name="SuccessfulUpgrade", unit=MetricUnit.Count, value=1)To support the proposal, a new MetricResolution enum should be added:
class MetricResolution(Enum):
Standard = 60
High = 1and changes should be made to the Metrics.add_metric method to allow for a new optional parameter.
Note
The EMF specification states that if a value is not provided, then a default value of 60 is assumed (aka standard resolution). For this reason, if theresolutionparameter is not specified we won't add the resolution.
Alternative solutions
No response
Acknowledgment
- This feature request meets Lambda Powertools Tenets
- Should this be considered in other Lambda Powertools languages? i.e. Java, TypeScript