intelligence-router/tests/test_router_circuit_breaker.py

"""Tests for circuit breaker + OpenRouter fallback — Issue #6.

Circuit tracks Sidecar failures, falls back to OpenRouter when open,
resets on successful Sidecar interaction.
Uses conftest.py patches for URL mocking.
"""
import asyncio
import pytest
from httpx import Response, ASGITransport, AsyncClient
import respx

import main


class TestCircuitBreaker:
    """Tests for the circuit breaker mechanism."""

    def test_circuit_closed_initially(self):
        """Circuit starts closed (allows Sidecar requests)."""
        assert main._circuit_open is False
        assert main._recovery_attempts == 0

    def test_circuit_opens_after_max_failures(self):
        """Circuit opens after MAX_RECOVERY_ATTEMPTS failures."""
        for i in range(main.MAX_RECOVERY_ATTEMPTS):
            main.circuit_record_failure()
        assert main._circuit_open is True
        assert main._recovery_attempts == main.MAX_RECOVERY_ATTEMPTS

    def test_circuit_resets_on_success(self):
        """Circuit resets after a successful Sidecar interaction."""
        # Fill up recovery attempts to trigger open circuit
        for _ in range(main.MAX_RECOVERY_ATTEMPTS):
            main.circuit_record_failure()
        assert main._circuit_open is True
        main.circuit_reset()
        assert main._circuit_open is False

    def test_circuit_allows_request_when_closed(self):
        """Circuit allows Sidecar request when closed."""
        main.circuit_reset()
        result = asyncio.run(main.circuit_breaker_check())
        assert result is True

    def test_circuit_blocks_when_open(self):
        """Circuit blocks Sidecar request when open."""
        for _ in range(main.MAX_RECOVERY_ATTEMPTS):
            main.circuit_record_failure()
        result = asyncio.run(main.circuit_breaker_check())
        assert result is False


class TestOpenRouterFallback:
    """Tests for OpenRouter as fallback backend."""

    def test_router_uses_openrouter_when_circuit_open(self):
        """When circuit is open, router tries OpenRouter."""
        async def run_test():
            with respx.mock:
                # Sidecar is down
                respx.get("http://localhost:8081/models/status").mock(
                    side_effect=Exception("connection refused")
                )
                # OpenRouter works
                respx.post("https://openrouter.ai/v1/chat/completions").mock(
                    return_value=Response(200, json={"choices": [{"message": {"content": "Hello from OR"}}]})
                )
                transport = ASGITransport(app=main.app)
                async with AsyncClient(transport=transport, base_url="http://test") as ac:
                    resp = await ac.post(
                        "/v1/chat/completions",
                        json={"model": "qwen-3-8b", "messages": [{"role": "user", "content": "hi"}]},
                    )
                assert resp.status_code == 200
                data = resp.json()
                assert data["choices"][0]["message"]["content"] == "Hello from OR"
        asyncio.run(run_test())


class TestDeprecatedHeaderRemoved:
    """Verify x-intelligence-level header is removed."""

    def test_proxy_ignores_intelligence_level_header(self):
        """Router does not route based on x-intelligence-level: High."""
        async def run_test():
            with respx.mock:
                respx.get("http://localhost:8081/models/status").mock(
                    return_value=Response(200, json={"active_profile": "qwen-3-8b", "llama_server_running": True})
                )
                # Should route to Main PC regardless of header
                respx.post("http://localhost:8080/v1/chat/completions").mock(
                    return_value=Response(200, json={"choices": [{"message": {"content": "Hello"}}]})
                )
                transport = ASGITransport(app=main.app)
                async with AsyncClient(transport=transport, base_url="http://test") as ac:
                    resp = await ac.post(
                        "/v1/chat/completions",
                        json={"model": "qwen-3-8b", "messages": [{"role": "user", "content": "hi"}]},
                        headers={"x-intelligence-level": "High"},  # Should be ignored
                    )
                assert resp.status_code == 200
        asyncio.run(run_test())