/the-art-of-readable-code

🎼 Designing and Implementing a “Minute/Hour Counter”

Primary LanguagePython

The art of readable code

This repository contains the last chapter code example from the book "The art of readable code" by Dustin Boswell and Trevor Foucher written in Python.

Each directory contains a different example from the book.

Problem

We need to keep track of how many bytes a web server has transferred over the past minute and over the past hour. Here’s an illustration of how these totals are maintained:

Two dimensions graph of how many bytes a web server has transferred over the past minute and over the past hour.

Running the code

# to run naive solution
uv run python -i naive.py

# to run conveyor belt solution
uv run python -i conveyor_belt.py

# to run time bucket design solution
uv run -i time_bucket_design.py

counter = MinuteHourCounter()
counter.add(10)
counter.add(10)
counter.add(10)

print(counter.minute_count()) # 30
print(counter.hour_count()) # 30

Solution

solution lines of code cost per hour_count memory usage error in hour_count
Naive solution 49 O(#events-per-hour) (~3.6 million) unbounded 1 part per 3600
Conveyor belt 73 O(1) O(#events-per-hour)¹ 1 part per 3600
Time-bucketed 99 O(1) O(#buckets)² 1 part per 60

¹ - In the original c++ code, ~5mb

² - In the original c++ code, ~500 bytes