Registry / aws / lambda-warmer-py

lambda-warmer-py

library0.6.0pypypiunverified

A Python decorator to keep AWS Lambda functions warm and monitor cold starts. The decorator intercepts warmer invocations (typically from a CloudWatch Event) and returns a no-op response, while measuring cold start duration. Current version 0.6.0. Release cadence is low, last updated in 2020.

aws

pip install lambda-warmer-py

github ↗package ↗

INSTALL

IMPORT

SIG · LAMBDA-WARMER-PY

lambda-warmer-py

awspythonv0.6.0

Install

1.5s avg

Import

—

Disk

16MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.6.0 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.000s · 17.8MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 1.5s · import 0.000s · 18MB

16MB installed

● package 16MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

warmer

✓ from lambdawarmer import warmer

✗ from lambda_warmer import warmer

Decorate your Lambda handler with @warmer to handle warm-up pings and log cold start metrics.

from lambda_warmer import warmer @warmer def handler(event, context): return {'statusCode': 200, 'body': 'Hello World'}

Debug

Known issues

gotchaThe warmer decorator must be applied to the handler function that Lambda calls directly. If you wrap the handler inside another decorator, the warmer may not intercept invocations correctly.

fix

Ensure @warmer is the outermost decorator (closest to the function definition) or applied directly to the raw handler.

affects: all

deprecatedThe library uses boto3 to publish custom metrics to CloudWatch, but this requires IAM permissions (cloudwatch:PutMetricData). Without proper permissions, the decorator silently fails.

fix

Attach an IAM policy granting cloudwatch:PutMetricData to your Lambda execution role, or override the metric publishing logic.

affects: all

Upgrade

Version history

0.6.0latest on PyPI · released Nov 23, 2019

Audit

Dependencies

No dependency data recorded yet.

Agent activity

16 hits · last 30 days

node

Resources

githubhttps://github.com/robhowley/lambda-warmer-py ↗

packagehttps://pypi.org/project/lambda-warmer-py/ ↗