Python utilities for AWS Lambda functions including but not limited to tracing, logging and custom metric
Project description
Lambda Powertools
A suite of utilities for AWS Lambda Functions that makes tracing with AWS X-Ray, structured logging and creating custom metrics asynchronously easier - Currently available for Python only and compatible with Python >=3.6.
Status: Beta
Features
Tracing
It currently uses AWS X-Ray
- Decorators that capture cold start as annotation, and response and exceptions as metadata
- Run functions locally without code change to disable tracing
- Explicitly disable tracing via env var
POWERTOOLS_TRACE_DISABLED="true"
Logging
- Decorators that capture key fields from Lambda context, cold start and structures logging output as JSON
- Optionally log Lambda request when instructed (disabled by default)
- Enable via
POWERTOOLS_LOGGER_LOG_EVENT="true"
or explicitly via decorator param
- Enable via
- Logs canonical custom metric line to logs that can be consumed asynchronously
Environment variables used across suite of utilities
Environment variable | Description | Default | Utility |
---|---|---|---|
POWERTOOLS_SERVICE_NAME | Sets service name used for tracing namespace, metrics dimensions and structured logging | "service_undefined" | all |
POWERTOOLS_TRACE_DISABLED | Disables tracing | "false" | tracing |
POWERTOOLS_LOGGER_LOG_EVENT | Logs incoming event | "false" | logging |
LOG_LEVEL | Sets logging level | "INFO" | logging |
Usage
Installation
With pip installed, run: pip install aws-lambda-powertools
Tracing
Example SAM template using supported environment variables
Globals:
Function:
Tracing: Active # can also be enabled per function
Environment:
Variables:
POWERTOOLS_SERVICE_NAME: "payment"
POWERTOOLS_TRACE_DISABLED: "false"
Pseudo Python Lambda code
from aws_lambda_powertools.tracing import Tracer
tracer = Tracer()
# tracer = Tracer(service="payment") # can also be explicitly defined
@tracer.capture_method
def collect_payment(charge_id):
# logic
ret = requests.post(PAYMENT_ENDPOINT)
# custom annotation
tracer.put_annotation("PAYMENT_STATUS", "SUCCESS")
return ret
@tracer.capture_lambda_handler
def handler(event, context)
charge_id = event.get('charge_id')
payment = collect_payment(charge_id)
...
Logging
Example SAM template using supported environment variables
Globals:
Function:
Environment:
Variables:
POWERTOOLS_SERVICE_NAME: "payment"
LOG_LEVEL: "INFO"
Pseudo Python Lambda code
from aws_lambda_powertools.logging import logger_setup, logger_inject_lambda_context
logger = logger_setup()
# logger_setup(service="payment") # also accept explicit service name
# logger_setup(level="INFO") # also accept explicit log level
@logger_inject_lambda_context
def handler(event, context)
logger.info("Collecting payment")
...
# You can log entire objects too
logger.info({
"operation": "collect_payment",
"charge_id": event['charge_id']
})
...
Exerpt output in CloudWatch Logs
{
"timestamp":"2019-08-22 18:17:33,774",
"level":"INFO",
"location":"collect.handler:1",
"service":"payment",
"lambda_function_name":"test",
"lambda_function_memory_size":"128",
"lambda_function_arn":"arn:aws:lambda:eu-west-1:12345678910:function:test",
"lambda_request_id":"52fdfc07-2182-154f-163f-5f0f9a621d72",
"cold_start": "true",
"message": "Collecting payment"
}
{
"timestamp":"2019-08-22 18:17:33,774",
"level":"INFO",
"location":"collect.handler:15",
"service":"payment",
"lambda_function_name":"test",
"lambda_function_memory_size":"128",
"lambda_function_arn":"arn:aws:lambda:eu-west-1:12345678910:function:test",
"lambda_request_id":"52fdfc07-2182-154f-163f-5f0f9a621d72",
"cold_start": "true",
"message":{
"operation":"collect_payment",
"charge_id": "ch_AZFlk2345C0"
}
}
Custom Metrics async
This feature requires Custom Metrics SAR App in order to process canonical metric lines in CloudWatch Logs.
If you're starting from scratch, you may want to see a working example, tune to your needs and deploy within your account - Serverless Airline Log Processing Stack
from aws_lambda_powertools.logging import MetricUnit, log_metric
def handler(event, context)
log_metric(name="SuccessfulPayment", unit=MetricUnit.Count, value=10, namespace="MyApplication")
# Optional dimensions
log_metric(name="SuccessfulPayment", unit=MetricUnit.Count, value=10, namespace="MyApplication", customer_id="123-abc", charge_id="abc-123")
# Explicit service name
log_metric(service="paymentTest", name="SuccessfulPayment", namespace="MyApplication".....)
...
Exerpt output in CloudWatch Logs
MONITORING|10|Count|SuccessfulPayment|MyApplication|service="payment
MONITORING|10|Count|SuccessfulPayment|MyApplication|customer_id="123-abc",charge_id="abc-123",service="payment
MONITORING|10|Count|SuccessfulPayment|MyApplication|service="paymentTest
Beta
This library may change its API/methods or environment variables as it receives feedback from customers. Currently looking for ideas in the following areas before making it stable:
- Should Tracer patch all possible imported libraries by default or only AWS SDKs?
- Patching all libraries may have a small performance penalty (~50ms) at cold start
- Alternatively, we could patch only AWS SDK if available and to provide a param to patch multiple
Tracer(modules=("boto3", "requests"))
- Create a Tracer provider to support additional tracing
- Either duck typing or ABC to allow additional tracing providers
TODO
- Enable CI
- Add an example code using powertools
Credits
- Structured logging initial implementation from aws-lambda-logging
- Powertools idea DAZN Powertools
License
This library is licensed under the MIT-0 License. See the LICENSE file.
HISTORY
November 15th, 2019
- Public beta release
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distribution
Built Distribution
Hashes for aws_lambda_powertools-0.3.0.tar.gz
Algorithm | Hash digest | |
---|---|---|
SHA256 | cf3860c0c02a04280d09f60b9f83a7d643a64deb73f3b653b998725b4bce4c24 |
|
MD5 | db6a9d65e9966a93e2b4d4e33c7c2abb |
|
BLAKE2b-256 | 8428bd034587c0427efe1bf6509dda87127fef0f1a5e2f7c5b5e95be376737d9 |
Hashes for aws_lambda_powertools-0.3.0-py2.py3-none-any.whl
Algorithm | Hash digest | |
---|---|---|
SHA256 | 79902be859182fab40a521d02bab6481cfdc6711052a13772b1fed15deaa98fa |
|
MD5 | 55944299f9c5a44a08f1899c4d063ae8 |
|
BLAKE2b-256 | eb0917061d4cb73df1f65e1b7a4837557c9337200df8e15e1033ceb5c5c1a3cf |