lambda-failure-lab

Lab scenarios for Lambda-style failure modes: timeouts, transient retries, and throttling. Includes a small client-side exponential backoff helper for exercising those failures.

Scenarios

• scenarios/timeout — handler that can sleep past a configured timeout
• scenarios/retry — handler that raises a transient error
• scenarios/throttle — handler that simulates 429 / rate-limit responses

The JSON catalog output (python -m scenarios.catalog --format json) now includes scenario_id, description, and tags for each entry so downstream tooling can filter by capability without parsing free-form text.

Client helpers

• clients/backoff.py — exponential backoff retries
• clients/circuit_breaker.py — open the circuit after repeated failures

Client helper

from clients.backoff import retry_with_backoff
from scenarios.retry.handler import TransientError, handler

result = retry_with_backoff(
    lambda: handler({}),
    retries=3,
    retry_on=(TransientError,),
)

Tests

python -m unittest discover -s tests -v

CI

GitHub Actions runs the unit tests on every push and pull request.