Skip to content

Level 3 / Project 13 - Quality Gate Runner

Home: README

Learn Your Way

Read Build Watch Test Review Visualize Try
— This project — — Flashcards — Browser

Estimated time: 55 minutes

Focus

  • simulate lint/test/build gate process

Why this project exists

This project gives you level-appropriate practice in a realistic operations context. Goal: run the baseline, alter behavior, break one assumption, recover safely, and explain the fix.

Run (copy/paste)

Use <repo-root> as the folder containing this repository's README.md.

cd <repo-root>/projects/level-3/13-quality-gate-runner
python project.py project.py
python project.py project.py --json
python project.py project.py --max-lines 100
pytest -q

Expected terminal output

Pipeline: FAIL (5.2ms)
  [PASS] file_exists:project.py: File found
  [PASS] syntax:project.py: No syntax errors
  [FAIL] no_print:project.py: 3 print statement(s) found
  [PASS] size:project.py: 165 lines (limit: 300)
3/4 gates passed
14 passed

Expected artifacts

  • Pipeline results on stdout
  • Passing tests
  • Updated notes.md

Checkpoint: Baseline code runs and all tests pass. Commit your work before continuing.

Alter it (required) — Extension

  1. Add a check_docstrings gate that verifies all functions have docstrings.
  2. Add a --gate flag to run only specific gates.
  3. Add --strict mode where any warning is treated as a failure.

Break it (required) — Core

  1. Run on a non-Python file — do syntax and print checks handle it?
  2. Run on a file that doesn't exist — does the pipeline still report all gates?
  3. Set --max-lines 0 — does the size check handle the edge case?

Fix it (required) — Core

  1. Add file type detection (skip syntax check for non-.py files).
  2. Ensure all gates handle missing files consistently.
  3. Add a --quiet flag that only shows failures.

Checkpoint: All modifications done, tests still pass. Good time to review your changes.

Explain it (teach-back)

  1. What is a "quality gate" in CI/CD and how does this project simulate one?
  2. How does compile() check for syntax errors without running the code?
  3. Why use time.perf_counter() instead of time.time() for timing?
  4. How does the pipeline aggregate individual gate results?

Mastery check

You can move on when you can: - build composable quality gate checks, - use compile() for syntax validation, - aggregate results into a pass/fail pipeline, - time operations with time.perf_counter().

← Prev Home Next →