test_resilience.py

"""Tests for resilience patterns."""

import pytest
from utils.resilience.circuit_breaker import CircuitBreaker, CircuitState
from utils.resilience.retry import retry_with_backoff


def test_circuit_breaker_closed():
    """Test circuit breaker in closed state."""
    breaker = CircuitBreaker(failure_threshold=3)
    
    def success_func():
        return "success"
    
    result = breaker.call(success_func)
    assert result == "success"
    assert breaker.state == CircuitState.CLOSED
    assert breaker.failure_count == 0


def test_circuit_breaker_opens_after_failures():
    """Test circuit breaker opens after threshold failures."""
    breaker = CircuitBreaker(failure_threshold=3)
    
    def failing_func():
        raise Exception("Test failure")
    
    # Fail 3 times to open circuit
    for _ in range(3):
        with pytest.raises(Exception):
            breaker.call(failing_func)
    
    assert breaker.state == CircuitState.OPEN
    assert breaker.failure_count >= 3


def test_retry_with_backoff_success():
    """Test retry succeeds eventually."""
    attempts = []
    
    @retry_with_backoff(max_attempts=3, base_delay=0.1)
    def flaky_func():
        attempts.append(1)
        if len(attempts) < 2:
            raise Exception("Temporary failure")
        return "success"
    
    result = flaky_func()
    assert result == "success"
    assert len(attempts) == 2


def test_retry_with_backoff_exhaustion():
    """Test retry exhausts all attempts."""
    attempts = []
    
    @retry_with_backoff(max_attempts=3, base_delay=0.1)
    def always_fails():
        attempts.append(1)
        raise ValueError("Always fails")
    
    with pytest.raises(ValueError):
        always_fails()
    
    assert len(attempts) == 3