production/tests/test_integration.py

"""
Integration tests for ml-intern production server.

Tests cover:
- Rate limiting across distributed instances
- Circuit breaker state transitions
- Cache hit/miss behavior
- Budget enforcement
- Session isolation
- Health check endpoints
- Graceful shutdown handling
"""

import asyncio
import hashlib
import json
import os
import sys
import time
import uuid
from unittest.mock import AsyncMock, MagicMock, patch

import pytest
import redis.asyncio as aioredis

sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))

from production_server import (
    CircuitBreaker,
    ConcurrencyLimiter,
    CostTracker,
    RedisManager,
    generate_cache_key,
    get_provider_from_model,
    estimate_cost,
    ChatRequest,
)


@pytest.fixture
async def redis_manager():
    manager = MagicMock(spec=RedisManager)
    manager.get_cache = AsyncMock(return_value=None)
    manager.set_cache = AsyncMock()
    manager.delete_cache = AsyncMock()
    async def check_limit(key, rpm):
        return True, 0.0
    manager.check_rate_limit = check_limit
    async def get_circuit(provider):
        return {"state": "closed", "failures": 0, "last_failure": 0}
    manager.get_circuit_state = get_circuit
    async def set_circuit(provider, state):
        pass
    manager.set_circuit_state = set_circuit
    yield manager


@pytest.fixture
def concurrency_limiter():
    return ConcurrencyLimiter(10)


class TestProviderResolution:
    def test_cloud_providers(self):
        assert get_provider_from_model("anthropic/claude-opus-4") == ("anthropic", "anthropic/claude-opus-4")
        assert get_provider_from_model("openai/gpt-5") == ("openai", "openai/gpt-5")
    
    def test_free_tier_providers(self):
        assert get_provider_from_model("groq/llama-3.3-70b") == ("groq", "llama-3.3-70b")
    
    def test_nim_provider(self):
        assert get_provider_from_model("nim/llama-3-8b") == ("nim", "llama-3-8b")
        assert get_provider_from_model("nim/llama-3.1-405b-instruct") == ("nim", "llama-3.1-405b-instruct")
    
    def test_local_providers(self):
        assert get_provider_from_model("ollama/llama3.1") == ("ollama", "llama3.1")
        assert get_provider_from_model("vllm/llama-3-8b") == ("vllm", "llama-3-8b")
        assert get_provider_from_model("llamacpp/llama-3-8b") == ("llamacpp", "llama-3-8b")
        assert get_provider_from_model("lmstudio/llama-3-8b") == ("lmstudio", "llama-3-8b")
        assert get_provider_from_model("mlx/llama-3-8b") == ("mlx", "llama-3-8b")
        assert get_provider_from_model("tgi/llama-3-8b") == ("tgi", "llama-3-8b")
        assert get_provider_from_model("local/my-model") == ("local", "my-model")
    
    def test_default_provider(self):
        assert get_provider_from_model("some-model") == ("huggingface", "some-model")


class TestCostEstimation:
    def test_anthropic_cost(self):
        cost = estimate_cost("anthropic", "claude-opus-4", 1000000, 1000000)
        assert abs(cost - 90.0) < 1
    
    def test_openai_cost(self):
        cost = estimate_cost("openai", "gpt-5", 1000000, 1000000)
        assert abs(cost - 12.5) < 1
    
    def test_free_providers_zero_cost(self):
        for provider in ["groq", "nim", "ollama", "vllm", "llamacpp", "lmstudio", "mlx", "tgi", "local", "huggingface"]:
            cost = estimate_cost(provider, "test-model", 1000000, 1000000)
            assert cost == 0.0, f"Provider {provider} should have zero cost"


class TestCacheKeyGeneration:
    def test_deterministic_keys(self):
        req1 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "Hello"}],
            temperature=0.7,
        )
        req2 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "Hello"}],
            temperature=0.7,
        )
        assert generate_cache_key(req1) == generate_cache_key(req2)
    
    def test_different_content_different_keys(self):
        req1 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "Hello"}],
        )
        req2 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "World"}],
        )
        assert generate_cache_key(req1) != generate_cache_key(req2)
    
    def test_stream_not_in_cache_key(self):
        req1 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "Hello"}],
            stream=False,
        )
        req2 = ChatRequest(
            model="groq/llama-3.3-70b",
            messages=[{"role": "user", "content": "Hello"}],
            stream=True,
        )
        assert generate_cache_key(req1) == generate_cache_key(req2)


class TestCircuitBreaker:
    @pytest.mark.asyncio
    async def test_initially_closed(self, redis_manager):
        cb = CircuitBreaker(redis_manager, "groq")
        assert await cb.can_execute()
    
    @pytest.mark.asyncio
    async def test_opens_after_threshold(self, redis_manager):
        cb = CircuitBreaker(redis_manager, "groq")
        for _ in range(5):
            await cb.record_failure()
        redis_manager.get_circuit_state = AsyncMock(return_value={
            "state": "open",
            "failures": 5,
            "last_failure": time.time(),
        })
        assert not await cb.can_execute()
    
    @pytest.mark.asyncio
    async def test_half_open_after_timeout(self, redis_manager):
        cb = CircuitBreaker(redis_manager, "groq")
        redis_manager.get_circuit_state = AsyncMock(return_value={
            "state": "open",
            "failures": 5,
            "last_failure": time.time() - 120,
        })
        assert await cb.can_execute()
    
    @pytest.mark.asyncio
    async def test_closes_on_success(self, redis_manager):
        cb = CircuitBreaker(redis_manager, "groq")
        redis_manager.get_circuit_state = AsyncMock(return_value={
            "state": "half-open",
            "failures": 0,
            "last_failure": 0,
        })
        await cb.record_success()
        redis_manager.get_circuit_state = AsyncMock(return_value={
            "state": "closed",
            "failures": 0,
            "last_failure": 0,
        })
        assert await cb.can_execute()


class TestBudgetTracking:
    def test_can_spend_within_budget(self):
        tracker = CostTracker("session-1", budget_usd=10.0)
        assert tracker.can_spend(5.0)
    
    def test_cannot_exceed_budget(self):
        tracker = CostTracker("session-1", budget_usd=10.0)
        tracker.spent_usd = 8.0
        assert not tracker.can_spend(3.0)
    
    def test_exact_budget_boundary(self):
        tracker = CostTracker("session-1", budget_usd=10.0)
        tracker.spent_usd = 5.0
        assert tracker.can_spend(5.0)
        assert not tracker.can_spend(5.01)
    
    def test_zero_budget(self):
        tracker = CostTracker("session-1", budget_usd=0.0)
        assert not tracker.can_spend(0.01)


class TestConcurrencyLimiter:
    @pytest.mark.asyncio
    async def test_acquire_release(self):
        limiter = ConcurrencyLimiter(2)
        await limiter.acquire()
        limiter.release()
        assert True
    
    @pytest.mark.asyncio
    async def test_blocks_at_limit(self):
        limiter = ConcurrencyLimiter(1)
        await limiter.acquire()
        task = asyncio.create_task(limiter.acquire())
        await asyncio.sleep(0.1)
        limiter.release()
        await asyncio.wait_for(task, timeout=2.0)


class TestRateLimiting:
    @pytest.mark.asyncio
    async def test_token_bucket_allows_requests(self):
        manager = MagicMock()
        async def mock_check(key, rpm):
            return True, 0.0
        manager.check_rate_limit = mock_check
        allowed, retry = await manager.check_rate_limit("groq:session-1", 40)
        assert allowed
        assert retry == 0.0
    
    @pytest.mark.asyncio
    async def test_token_bucket_denies_when_empty(self):
        manager = MagicMock()
        async def mock_check_denied(key, rpm):
            return False, 1.5
        manager.check_rate_limit = mock_check_denied
        allowed, retry = await manager.check_rate_limit("groq:session-1", 40)
        assert not allowed
        assert retry > 0


class TestEndToEndFlow:
    @pytest.mark.asyncio
    async def test_full_request_flow(self, redis_manager):
        session_id = str(uuid.uuid4())
        provider = "groq"
        model = "llama-3.3-70b-versatile"
        allowed, _ = await redis_manager.check_rate_limit(f"{provider}:{session_id}", 30)
        assert allowed
        tracker = CostTracker(session_id, budget_usd=10.0)
        estimated_cost = estimate_cost(provider, model, 1000, 500)
        assert tracker.can_spend(estimated_cost)
        cb = CircuitBreaker(redis_manager, provider)
        assert await cb.can_execute()
        tracker.record_spend(estimated_cost)
        await cb.record_success()
        assert tracker.spent_usd > 0
        assert tracker.spent_usd <= tracker.budget_usd


if __name__ == "__main__":
    pytest.main([__file__, "-v"])