Fix DB integration quality: dependency injection, idempotent seeding, price precision, and test isolation

app/api/routes.py

@@ -1,16 +1,35 @@
 """API route definitions for NX AI."""
 
-from fastapi import APIRouter
-from pydantic import BaseModel
 import os
-from dotenv import load_dotenv
+import time
+
 import psycopg2
-router = APIRouter()
+from dotenv import load_dotenv
+from fastapi import APIRouter, Depends
+from pydantic import BaseModel
 
+from app import __version__
+
+load_dotenv()
 
 router = APIRouter()
 
 
+def get_db_connection():  # type: ignore[return]
+    """Create and yield a PostgreSQL connection for use as a FastAPI dependency."""
+    conn = psycopg2.connect(
+        host=os.getenv('DB_HOST'),
+        port=os.getenv('DB_PORT', '5432'),
+        dbname=os.getenv('DB_NAME'),
+        user=os.getenv('DB_USER'),
+        password=os.getenv('DB_PASSWORD'),
+    )
+    try:
+        yield conn
+    finally:
+        conn.close()
+
+
 class EchoRequest(BaseModel):
     """Request body for the echo endpoint."""
 
@@ -23,44 +42,32 @@ class EchoResponse(BaseModel):
     echo: str
 
 
-
-import time
-import sys
-from app import __version__
-
 @router.get("/")
-def root() -> dict:
+def root(conn=Depends(get_db_connection)) -> dict:
     """Return a structured welcome message for the API root, including product data."""
-    load_dotenv()
-    conn = psycopg2.connect(
-        host=os.getenv('DB_HOST'),
-        port=os.getenv('DB_PORT', '5432'),
-        dbname=os.getenv('DB_NAME'),
-        user=os.getenv('DB_USER'),
-        password=os.getenv('DB_PASSWORD')
-    )
     cur = conn.cursor()
-    cur.execute('SELECT id, name, description, price, in_stock, created_at FROM product;')
-    products = [
-        {
-            "id": row[0],
-            "name": row[1],
-            "description": row[2],
-            "price": float(row[3]),
-            "in_stock": row[4],
-            "created_at": row[5].isoformat() if row[5] else None
-        }
-        for row in cur.fetchall()
-    ]
-    cur.close()
-    conn.close()
+    try:
+        cur.execute('SELECT id, name, description, price, in_stock, created_at FROM product;')
+        products = [
+            {
+                "id": row[0],
+                "name": row[1],
+                "description": row[2],
+                "price": str(row[3]) if row[3] is not None else None,
+                "in_stock": row[4],
+                "created_at": row[5].isoformat() if row[5] else None,
+            }
+            for row in cur.fetchall()
+        ]
+    finally:
+        cur.close()
     epoch = int(time.time() * 1000)
     meta = {
         "version": __version__,
         "time": time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()),
         "epoch": epoch,
         "severity": "success",
-        "message": f"NX AI says hello. Returned {len(products)} products."
+        "message": f"NX AI says hello. Returned {len(products)} products.",
     }
     return {"meta": meta, "data": products}
 

app/main.py

@@ -2,12 +2,13 @@
 
 from fastapi import FastAPI
 
+from app import __version__
 from app.api.routes import router
 
 app = FastAPI(
     title="NX AI",
     description="Production-ready Python FastAPI app for NX",
-    version="1.0.0",
+    version=__version__,
 )
 
 app.include_router(router)

app/print_products.py

@@ -1,23 +1,29 @@
 import os
-from dotenv import load_dotenv
+
 import psycopg2
+from dotenv import load_dotenv
 
-load_dotenv()
 
-conn = psycopg2.connect(
-    host=os.getenv('DB_HOST'),
-    port=os.getenv('DB_PORT', '5432'),
-    dbname=os.getenv('DB_NAME'),
-    user=os.getenv('DB_USER'),
-    password=os.getenv('DB_PASSWORD')
-)
-cur = conn.cursor()
+def main() -> None:
+    load_dotenv()
 
-cur.execute('SELECT * FROM product;')
-rows = cur.fetchall()
+    conn = psycopg2.connect(
+        host=os.getenv('DB_HOST'),
+        port=os.getenv('DB_PORT', '5432'),
+        dbname=os.getenv('DB_NAME'),
+        user=os.getenv('DB_USER'),
+        password=os.getenv('DB_PASSWORD'),
+    )
+    cur = conn.cursor()
+    try:
+        cur.execute('SELECT * FROM product;')
+        rows = cur.fetchall()
+        for row in rows:
+            print(row)
+    finally:
+        cur.close()
+        conn.close()
 
-for row in rows:
-    print(row)
 
-cur.close()
-conn.close()
+if __name__ == "__main__":
+    main()

app/seed_product_table.py

@@ -1,41 +1,48 @@
 import os
-from dotenv import load_dotenv
+
 import psycopg2
+from dotenv import load_dotenv
+
+
+def main() -> None:
+    load_dotenv()
+
+    conn = psycopg2.connect(
+        host=os.getenv('DB_HOST'),
+        port=os.getenv('DB_PORT', '5432'),
+        dbname=os.getenv('DB_NAME'),
+        user=os.getenv('DB_USER'),
+        password=os.getenv('DB_PASSWORD'),
+    )
+    cur = conn.cursor()
+    try:
+        # Create product table with a unique constraint on name for idempotent seeding
+        cur.execute('''
+        CREATE TABLE IF NOT EXISTS product (
+            id SERIAL PRIMARY KEY,
+            name VARCHAR(100) NOT NULL UNIQUE,
+            description TEXT,
+            price NUMERIC(10, 2) NOT NULL,
+            in_stock BOOLEAN DEFAULT TRUE,
+            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+        );
+        ''')
+
+        # Insert seed data; skip rows whose name already exists
+        cur.execute('''
+        INSERT INTO product (name, description, price, in_stock) VALUES
+            ('Widget', 'A useful widget', 19.99, TRUE),
+            ('Gadget', 'A fancy gadget', 29.99, TRUE),
+            ('Thingamajig', 'An interesting thingamajig', 9.99, FALSE)
+        ON CONFLICT (name) DO NOTHING;
+        ''')
+
+        conn.commit()
+        print("Product table created and seeded.")
+    finally:
+        cur.close()
+        conn.close()
+
 
-load_dotenv()
-
-# Database connection
-conn = psycopg2.connect(
-    host=os.getenv('DB_HOST'),
-    port=os.getenv('DB_PORT', '5432'),
-    dbname=os.getenv('DB_NAME'),
-    user=os.getenv('DB_USER'),
-    password=os.getenv('DB_PASSWORD')
-)
-cur = conn.cursor()
-
-# Create product table
-cur.execute('''
-CREATE TABLE IF NOT EXISTS product (
-    id SERIAL PRIMARY KEY,
-    name VARCHAR(100) NOT NULL,
-    description TEXT,
-    price NUMERIC(10, 2) NOT NULL,
-    in_stock BOOLEAN DEFAULT TRUE,
-    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
-);
-''')
-
-# Insert seed data
-cur.execute('''
-INSERT INTO product (name, description, price, in_stock) VALUES
-    ('Widget', 'A useful widget', 19.99, TRUE),
-    ('Gadget', 'A fancy gadget', 29.99, TRUE),
-    ('Thingamajig', 'An interesting thingamajig', 9.99, FALSE)
-ON CONFLICT DO NOTHING;
-''')
-
-conn.commit()
-cur.close()
-conn.close()
-print("Product table created and seeded.")
+if __name__ == "__main__":
+    main()

app/test_db_connection.py

@@ -1,33 +1,40 @@
-
-from dotenv import load_dotenv
 import os
+import sys
+
 import psycopg2
+from dotenv import load_dotenv
+
+
+def main() -> int:
+    load_dotenv()
+
+    db_host = os.getenv('DB_HOST')
+    db_port = os.getenv('DB_PORT', '5432')
+    db_name = os.getenv('DB_NAME')
+    db_user = os.getenv('DB_USER')
+    db_password = os.getenv('DB_PASSWORD')
+
+    print("Attempting connection with:")
+    print(f"Host: {db_host}")
+    print(f"Port: {db_port}")
+    print(f"Database: {db_name}")
+    print(f"User: {db_user}")
+
+    try:
+        conn = psycopg2.connect(
+            host=db_host,
+            port=db_port,
+            dbname=db_name,
+            user=db_user,
+            password=db_password,
+        )
+        print("Connection successful!")
+        conn.close()
+        return 0
+    except Exception as e:
+        print(f"Connection failed: {e}")
+        return 1
+
 
-# Load .env file
-load_dotenv()
-
-# Load environment variables
-db_host = os.getenv('DB_HOST')
-db_port = os.getenv('DB_PORT', '5432')
-db_name = os.getenv('DB_NAME')
-db_user = os.getenv('DB_USER')
-db_password = os.getenv('DB_PASSWORD')
-
-print("Attempting connection with:")
-print(f"Host: {db_host}")
-print(f"Port: {db_port}")
-print(f"Database: {db_name}")
-print(f"User: {db_user}")
-
-try:
-    conn = psycopg2.connect(
-        host=db_host,
-        port=db_port,
-        dbname=db_name,
-        user=db_user,
-        password=db_password
-    )
-    print("Connection successful!")
-    conn.close()
-except Exception as e:
-    print(f"Connection failed: {e}")
+if __name__ == "__main__":
+    sys.exit(main())

requirements.txt

@@ -2,3 +2,5 @@ fastapi>=0.110.0
 uvicorn[standard]>=0.29.0
 httpx>=0.27.0
 pytest>=8.1.0
+python-dotenv>=1.0.0
+psycopg2-binary>=2.9.0

tests/test_routes.py

@@ -1,12 +1,63 @@
 """Unit and integration tests for NX AI routes."""
 
+from unittest.mock import MagicMock
+
 from fastapi.testclient import TestClient
 
+from app.api.routes import get_db_connection
 from app.main import app
 
 client = TestClient(app)
 
 
+<<<<<<< copilot/sub-pr-7
+def _mock_db_dependency(rows=None):
+    """Return a FastAPI dependency override that yields a mock DB connection."""
+    if rows is None:
+        rows = []
+
+    def override():
+        mock_conn = MagicMock()
+        mock_cursor = MagicMock()
+        mock_conn.cursor.return_value = mock_cursor
+        mock_cursor.fetchall.return_value = rows
+        yield mock_conn
+
+    return override
+
+
+def test_root_returns_product_data() -> None:
+    """GET / should return meta and data with product list."""
+    app.dependency_overrides[get_db_connection] = _mock_db_dependency(rows=[])
+    try:
+        response = client.get("/")
+        assert response.status_code == 200
+        body = response.json()
+        assert "meta" in body
+        assert "data" in body
+        assert body["meta"]["severity"] == "success"
+        assert isinstance(body["data"], list)
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_root_returns_products_from_db() -> None:
+    """GET / should include product rows returned by the database."""
+    from datetime import datetime
+    from decimal import Decimal
+    mock_row = (1, "Widget", "A useful widget", Decimal("19.99"), True, datetime(2024, 1, 1, 0, 0, 0))
+    app.dependency_overrides[get_db_connection] = _mock_db_dependency(rows=[mock_row])
+    try:
+        response = client.get("/")
+        assert response.status_code == 200
+        body = response.json()
+        assert len(body["data"]) == 1
+        assert body["data"][0]["name"] == "Widget"
+        assert body["data"][0]["price"] == "19.99"
+        assert "Returned 1 products" in body["meta"]["message"]
+    finally:
+        app.dependency_overrides.clear()
+=======
 def test_root_returns_welcome_message() -> None:
     """GET / should return a welcome message."""
     response = client.get("/")
@@ -16,6 +67,7 @@ def test_root_returns_welcome_message() -> None:
     assert "data" in json_data
     assert "message" in json_data["meta"]
     assert "NX AI" in json_data["meta"]["message"]
+>>>>>>> staging
 
 
 def test_health_returns_ok() -> None: