Fast Api mock not working in pipeline attemps to connect to the db

[krivas]

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Example Code

from unittest.mock import MagicMock
import pytest 
from main import app
from routers.contacts import get_db


mock_session=MagicMock()

def override_get_db():
    try:
        yield mock_session
    finally:
        pass

app.dependency_overrides[get_db] =  override_get_db

@pytest.fixture
def mock_db_session():
    return mock_session

Description

I'm getting the error: "Can't connect to MySQL server on 'localhost' in the pipeline but it shouldn't because I'm mocking the connection with magic mock. The tests work perfectly in my local machine but not in the pipeline.

The error: ImportError while loading conftest '/home/runner/work/gitworkflow2/gitworkflow2/backend/tests/conftest.py'. tests/conftest.py:3: in from main import app main.py:11: in Base.metadata.create_all(bind=engine)

E sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'localhost' ([Errno 111] Connection refused)")

My code

from unittest.mock import MagicMock, patch
from data.models import Contact
from fastapi.testclient import TestClient
from routers.contacts import get_db
from main import app


client = TestClient(app)


def test_create_contact(mock_db_session):
    url="/contacts"
    contact={"first_name":"Giovanni",
             "last_name":"Rossi",
             "email":"giovanni@gmail.com",
             "phone_number":"1234567890" ,
             "user_id":1
             }

    response = client.post(url, json=contact)

    assert response.status_code == 201
    data = response.json()
    assert data["first_name"] == "Giovanni"
    assert data["last_name"] == "Rossi"
    assert data["phone_number"] == "1234567890"
    assert data["email"] == "giovanni@gmail.com"


    mock_db_session.add.assert_called_once()
    mock_db_session.commit.assert_called_once()
    mock_db_session.refresh.assert_called_once()

def test_create_without_user_id(mock_db_session):
    url="/contacts"
    contact={"first_name":"Giovanni",
             "last_name":"Rossi",
             "email":"giovanni@gmail.com",
             "phone_number":"1234567890" ,
             }

    response = client.post(url, json=contact)
    assert response.status_code == 422

def test_create_without_phone_number(mock_db_session):
    url="/contacts"
    contact={"first_name":"Giovanni",
             "last_name":"Rossi",
             "email":"giovanni@gmail.com",
             "user_id":1
             }

    response = client.post(url, json=contact)
    assert response.status_code == 422

def test_get_contacts(mock_db_session):

    mock_query = MagicMock()
    mock_query.filter.return_value.all.return_value = [
    {
        "last_name": "Rossi",
        "id": 68,
        "phone_number": "1234567890",
        "email": "giovanni@gmail.com",
        "user_id": 1,
        "first_name": "Giovanni"
    }
    ]

    mock_db_session.query.return_value = mock_query

    app.dependency_overrides[get_db] = lambda:mock_db_session
    response = client.get("/contacts/1")
    assert response.status_code == 200
    assert response.json() == [
    {
        "last_name": "Rossi",
        "id": 68,
        "phone_number": "1234567890",
        "email": "giovanni@gmail.com",
        "user_id": 1,
        "first_name": "Giovanni"
    }
    ]

def test_get_empty_contacts(mock_db_session):

    mock_query = MagicMock()
    mock_query.filter.return_value.all.return_value = []

    mock_db_session.query.return_value = mock_query

    app.dependency_overrides[get_db] = lambda:mock_db_session
    response = client.get("/contacts/1")
    assert response.status_code == 200
    assert response.json() == []

Main:

from fastapi import Depends, FastAPI
from fastapi.middleware.cors import CORSMiddleware
from typing import Annotated
from data.database import engine,SessionLocal
from data.models import Base
from sqlalchemy.orm import Session 
from routers import contacts, users

app = FastAPI()
Base.metadata.create_all(bind=engine)

def get_db():
    db=SessionLocal()
    try:
        yield db
    finally:
        db.close()

db_dependency=Annotated[Session,Depends(get_db)]
# Configure CORS to allow requests from your Angular frontend


origins = ["*"]

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)
app.include_router(contacts.router, prefix="/contacts", tags=["Contacts"])
app.include_router(users.router, prefix="/users", tags=["Users"])

@app.get("/health" ,tags=['Health'])
async def check_health():
    return {"Hello": "World"}

My pipeline

name: CI

on:
  push:
    branches:
      - main  # or the branch you want to trigger the workflow on

jobs:
  build:
    runs-on: ubuntu-latest

    strategy:
      matrix:
        python-version: [3.10.9]

    steps:
    - name: Checkout Repository
      uses: actions/checkout@v2  

    - name: Checkout Repository
      uses: actions/checkout@v2
    
    - name: Set up Python
      uses: actions/setup-python@v2
      with:
        python-version: ${{ matrix.python-version }}
        

        
    - name: Install Dependencies
      working-directory: ./backend
      run: |
        python3 -m venv venv
        source venv/bin/activate
        pip install --upgrade pip
        pip install -r requirements.txt
    - name: Run Tests
      working-directory: ./backend
      run: |
       source venv/bin/activate
       pip install mock
       python -m pytest tests/test_users.py

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.104.1

Pydantic Version

2.4.2

Python Version

3.10.9

Additional Context

No response

[krivas]

The problem was this line of code: Base.metadata.create_all(bind=engine). The mocking was working perfectly. The thing is that in the configuration, that creates all your models in the db. So, that should only be run manually . I modified to be a function for now and it worked perfectly in my pipeline.