Add pytest test files for microservices

- Created test files for GPU service (tests/test_main.py)
- Created test files for Marketplace service (tests/test_main.py)
- Created test files for Trading service (tests/test_main.py)
- Created test files for Governance service (tests/test_main.py)
- Created integration tests for API gateway (tests/test_gateway.py)
- Added pytest dependencies to all service pyproject.toml files
- Created TEST_COVERAGE_REQUIREMENTS.md documenting coverage targets and best practices

This completes Phase 8: Create pytest test files for microservices

apps/api-gateway/pyproject.toml

@@ -13,6 +13,12 @@ dependencies = [
     "aitbc-core",
 ]
 
+[project.optional-dependencies]
+test = [
+    "pytest>=7.4.0",
+    "pytest-asyncio>=0.21.0",
+]
+
 [build-system]
 requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"
@@ -21,3 +27,6 @@ build-backend = "poetry.core.masonry.api"
 packages = [
     { include = "api_gateway", from = "src" }
 ]
+
+[tool.poetry.extras]
+test = ["pytest", "pytest-asyncio"]

apps/api-gateway/tests/__init__.py

@@ -0,0 +1,3 @@
+"""
+API Gateway tests
+"""

apps/api-gateway/tests/test_gateway.py

@@ -0,0 +1,71 @@
+"""
+Test API Gateway routing
+"""
+
+import pytest
+from fastapi.testclient import TestClient
+
+from api_gateway.main import app
+
+
+@pytest.fixture
+def client():
+    """Create test client for API Gateway"""
+    return TestClient(app)
+
+
+def test_gateway_health_check(client):
+    """Test gateway health check endpoint"""
+    response = client.get("/health")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["status"] == "healthy"
+    assert data["service"] == "api-gateway"
+
+
+def test_service_registry(client):
+    """Test service registry endpoint"""
+    response = client.get("/services")
+    assert response.status_code == 200
+    data = response.json()
+    assert "services" in data
+    services = data["services"]
+    assert isinstance(services, list)
+    # Check that GPU service is registered
+    gpu_service = next((s for s in services if s["name"] == "gpu"), None)
+    assert gpu_service is not None
+    assert gpu_service["url"] == "http://localhost:8101"
+    assert "/gpu/*" in gpu_service["routes"]
+
+
+def test_gpu_route_proxy(client):
+    """Test that gateway proxies requests to GPU service"""
+    # This test requires GPU service to be running
+    # In CI, this would be mocked or services would be started
+    response = client.get("/gpu/health")
+    # May fail if service not running, but tests routing logic
+    assert response.status_code in [200, 503]  # 503 if service down
+
+
+def test_marketplace_route_proxy(client):
+    """Test that gateway proxies requests to Marketplace service"""
+    response = client.get("/marketplace/health")
+    assert response.status_code in [200, 503]
+
+
+def test_trading_route_proxy(client):
+    """Test that gateway proxies requests to Trading service"""
+    response = client.get("/trading/health")
+    assert response.status_code in [200, 503]
+
+
+def test_governance_route_proxy(client):
+    """Test that gateway proxies requests to Governance service"""
+    response = client.get("/governance/health")
+    assert response.status_code in [200, 503]
+
+
+def test_unknown_route(client):
+    """Test that unknown routes return 404"""
+    response = client.get("/unknown/path")
+    assert response.status_code == 404