Python: Simple JSON Structured Logging

Hello! If you're setting up JSON logging in AWS lambda, check out this instead. You need some extra code to prevent duplicate log messages. Recently, I've been switching to logs structured as JSON. Using the sample command in my pattern for production-ready Python scripts, that means we replace delimited-strings like these: With JSON objects like … Continue reading Python: Simple JSON Structured Logging

Lambda: Building Python 3 Packages

Hello! This is a guide for building lambda zip packages with pip dependencies in Python 3. It expands the AWS guide to: Build your code if it's either a single-file Python module or a pip-installable Python package (e.g. contains a setup.py). Track pip dependencies for single-file Python modules in the standard requirements.txt file. Show the file … Continue reading Lambda: Building Python 3 Packages

CloudWatch Logs Structured as JSON with Python Lambda Functions

Hello! If you're setting up JSON logging in a script and instead of a lambda function, check out this instead. The pattern is a little simpler. Recently, I've been switching to logs structured as JSON. That means output like this: Instead of this: This way, your log processor can reference keys in a JSON object … Continue reading CloudWatch Logs Structured as JSON with Python Lambda Functions

Simplifying Messy Conditions: Adaptive Models

Hello! Today we're getting into the thorns of programming. Beware cactus. 🌵 Years ago I found Martin Fowler's article on Adaptive Models. Adaptive models let you replace nests of conditions with a declaration of actions. That pattern has helped clean up my DevOps code a ton of times. Fowler is a better programmer than me. His … Continue reading Simplifying Messy Conditions: Adaptive Models

Python DevOps Code Error Checking: Lint with Pyflakes

Hello! For those unfamiliar with linting (static analysis), read Dan Bader's introduction. There are several linters for Python, but when I'm doing DevOps I use Pyflakes. I love the opening sentence of its design principals: Pyflakes makes a simple promise: it will never complain about style, and it will try very, very hard to never … Continue reading Python DevOps Code Error Checking: Lint with Pyflakes

CodePipeline: Python AWS Lambda Functions Without Timeouts

Hello! Today we're going to cover how to add Python AWS lambda functions to CodePipeline, and specifically how to do that without getting stuck in timeout loops you can't cancel. Copy/pastable code first, details below. Replace the two highlighted lines with the code you actually need to run in the pipeline. The commented raise is … Continue reading CodePipeline: Python AWS Lambda Functions Without Timeouts

Boto3 Best Practices: Assert to Stop Silent Failures

Good morning! Today's post covers a pattern I use to increase my confidence that my infrastructure code is working. It turns silent errors into loud ones. I've handled plenty of code that runs without errors but still ends up doing the wrong thing, so I'm never really sure if it's safe to go to sleep … Continue reading Boto3 Best Practices: Assert to Stop Silent Failures