Testing Patterns

The backend uses pytest to validate internal execution boundaries, route handlers, and data transformation logic.

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1. Test Directory Layout

backend/tests/
├── conftest.py                 # Shared execution fixtures and mocked services
├── test_auth.py                # Asserts password verification and JWT logic
├── test_dashboard_routes.py    # Validates REST payload mapping and SSE stream structure
└── test_security_scrubbing.py  # Tests pre-execution SQL regex sanitization

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2. Core Testing Strategies

A. Isolated Unit Execution

Unit tests run isolated from external network dependencies. Tests replace downstream network calls to MongoDB and LLM API providers with mock objects (unittest.mock) to verify localized logic: - Pydantic Validation: Asserts that malformed edge request payloads raise validation errors before hitting route logic. - SQL Sanitization: Tests the regex scrubbing module against arrays of malicious query injection strings to ensure destructive commands are caught.

B. Route Integration via TestClient

To test route execution and dependency injection, tests use fastapi.testclient.TestClient. This allows simulating full HTTP request cycles directly against the initialized application instance:

from fastapi.testclient import TestClient
from backend.app import app

client = TestClient(app)

def test_unauthenticated_access_rejection():
    """Asserts that unauthenticated requests to protected endpoints return 401."""
    response = client.post("/dashboard/generate", json={"user_prompt": "test", "connection_name": "db"})
    assert response.status_code == 401