A suite of utilities for AWS Lambda functions to ease adopting best practices such as tracing, structured logging, custom metrics, and more.
Looking for a quick read through how the core features are used?
Check out this detailed blog post with a practical example.
This project separates core utilities that will be available in other runtimes vs general utilities that might not be available across all runtimes.
- AWS Lambda only. We optimise for AWS Lambda function environments and supported runtimes only. Utilities might work with web frameworks and non-Lambda environments, though they are not officially supported.
- Eases the adoption of best practices. The main priority of the utilities is to facilitate best practices adoption, as defined in the AWS Well-Architected Serverless Lens; all other functionality is optional.
- Keep it lean. Additional dependencies are carefully considered for security and ease of maintenance, and prevent negatively impacting startup time.
- We strive for backwards compatibility. New features and changes should keep backwards compatibility. If a breaking change cannot be avoided, the deprecation and migration process should be clearly defined.
- We work backwards from the community. We aim to strike a balance of what would work best for 80% of customers. Emerging practices are considered and discussed via Requests for Comment (RFCs)
- Idiomatic. Utilities follow programming language idioms and language-specific best practices.
Powertools is available in PyPi. You can use your favourite dependency management tool to install it
Quick hello world example using SAM CLI
Powertools is also available as a Lambda Layer, and it is distributed via the AWS Serverless Application Repository (SAR) to support semantic versioning.
|aws-lambda-powertools-python-layer||arn:aws:serverlessrepo:eu-west-1:057560766410:applications/aws-lambda-powertools-python-layer||Core dependencies only; sufficient for nearly all utilities.|
|aws-lambda-powertools-python-layer-extras||arn:aws:serverlessrepo:eu-west-1:057560766410:applications/aws-lambda-powertools-python-layer-extras||Core plus extra dependencies such as
Layer-extras does not support Python 3.6 runtime. This layer also includes all extra dependencies:
If using SAM, you can include this SAR App as part of your shared Layers stack, and lock to a specific semantic version. Once deployed, it'll be available across the account this is deployed to.
1 2 3 4 5 6 7 8 9 10 11 12 13
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Example of least-privileged IAM permissions to deploy Layer
Credits to mwarkentin for providing the scoped down IAM permissions.
The region and the account id for
GetCfnTemplate are fixed.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
You can fetch available versions via SAR API with:
|Tracing||Decorators and utilities to trace Lambda function handlers, and both synchronous and asynchronous functions|
|Logger||Structured logging made easier, and decorator to enrich structured logging with key Lambda context details|
|Metrics||Custom Metrics created asynchronously via CloudWatch Embedded Metric Format (EMF)|
|Event handler: AppSync||AppSync event handler for Lambda Direct Resolver and Amplify GraphQL Transformer function|
|Event handler: API Gateway and ALB||Amazon API Gateway REST/HTTP API and ALB event handler for Lambda functions invoked using Proxy integration|
|Middleware factory||Decorator factory to create your own middleware to run logic before, and after each Lambda invocation|
|Parameters||Retrieve parameter values from AWS Systems Manager Parameter Store, AWS Secrets Manager, or Amazon DynamoDB, and cache them for a specific amount of time|
|Batch processing||Handle partial failures for AWS SQS batch processing|
|Typing||Static typing classes to speedup development in your IDE|
|Validation||JSON Schema validator for inbound events and responses|
|Event source data classes||Data classes describing the schema of common Lambda event triggers|
|Parser||Data parsing and deep validation using Pydantic|
|Idempotency||Idempotent Lambda handler|
|Feature Flags||A simple rule engine to evaluate when one or multiple features should be enabled depending on the input|
Explicit parameters take precedence over environment variables.
|POWERTOOLS_SERVICE_NAME||Sets service name used for tracing namespace, metrics dimension and structured logging||All||
|POWERTOOLS_METRICS_NAMESPACE||Sets namespace used for metrics||Metrics||
|POWERTOOLS_TRACE_DISABLED||Explicitly disables tracing||Tracing||
|POWERTOOLS_TRACER_CAPTURE_RESPONSE||Captures Lambda or method return as metadata.||Tracing||
|POWERTOOLS_TRACER_CAPTURE_ERROR||Captures Lambda or method exception as metadata.||Tracing||
|POWERTOOLS_TRACE_MIDDLEWARES||Creates sub-segment for each custom middleware||Middleware factory||
|POWERTOOLS_LOGGER_LOG_EVENT||Logs incoming event||Logging||
|POWERTOOLS_LOGGER_SAMPLE_RATE||Debug log sampling||Logging||
|POWERTOOLS_LOG_DEDUPLICATION_DISABLED||Disables log deduplication filter protection to use Pytest Live Log feature||Logging||
|POWERTOOLS_EVENT_HANDLER_DEBUG||Enables debugging mode for event handler||Event Handler||
|LOG_LEVEL||Sets logging level||Logging||
As a best practice, AWS Lambda Powertools logging statements are suppressed. If necessary, you can enable debugging using
1 2 3