test: add pytest suite for API endpoints

- Add tests for /health, /predict (valid, invalid data, missing auth)
- Add conftest.py with mocked pipeline fixture and test payload
- Add pytest.ini with pythonpath config
- Add pytest and pytest-cov dependencies to requirements.txt

pytest.ini

@@ -0,0 +1,2 @@
+[pytest]
+pythonpath = .

requirements.txt

@@ -3,6 +3,7 @@ annotated-types==0.7.0
 anyio==4.12.1
 certifi==2026.2.25
 click==8.3.1
+coverage==7.13.4
 dnspython==2.8.0
 email-validator==2.3.0
 fastapi==0.133.1
@@ -14,18 +15,23 @@ httpcore==1.0.9
 httptools==0.7.1
 httpx==0.28.1
 idna==3.11
+iniconfig==2.3.0
 Jinja2==3.1.6
 joblib==1.5.3
 markdown-it-py==4.0.0
 MarkupSafe==3.0.3
 mdurl==0.1.2
 numpy==2.4.2
+packaging==26.0
 pandas==3.0.1
+pluggy==1.6.0
 pydantic==2.12.5
 pydantic-extra-types==2.11.0
 pydantic-settings==2.13.1
 pydantic_core==2.41.5
 Pygments==2.19.2
+pytest==9.0.2
+pytest-cov==7.0.0
 python-dateutil==2.9.0.post0
 python-dotenv==1.2.1
 python-multipart==0.0.22

tests/conftest.py

@@ -0,0 +1,36 @@
+import pytest
+from unittest.mock import MagicMock, patch
+from fastapi.testclient import TestClient
+from app.main import app
+
+TEST_API_KEY = "test-secret-key"
+
+VALID_PAYLOAD = {
+    "age": 35, "genre": 1, "statut_marital": "Marié(e)",
+    "poste": "Consultant", "domaine_etude": "Infra & Cloud",
+    "niveau_education": 3, "nombre_experiences_precedentes": 2,
+    "annee_experience_totale": 10, "annees_dans_l_entreprise": 5,
+    "annees_dans_le_poste_actuel": 2, "annees_sous_responsable_actuel": 3,
+    "annees_depuis_la_derniere_promotion": 1,
+    "note_evaluation_actuelle": 3, "note_evaluation_precedente": 3,
+    "augmentation_salaire_precedente": 15, "nb_formations_suivies": 2,
+    "nombre_participation_pee": 1,
+    "satisfaction_employee_environnement": 3,
+    "satisfaction_employee_nature_travail": 4,
+    "satisfaction_employee_equipe": 3,
+    "satisfaction_employee_equilibre_pro_perso": 2,
+    "heure_supplementaires": 0, "frequence_deplacement": 1,
+    "distance_domicile_travail": 10, "revenu_mensuel": 5000,
+}
+
+@pytest.fixture(scope="module")
+def client():
+    mock_pipeline = MagicMock()
+    # Simule predict_proba → [[proba_reste, proba_quitte]]
+    # 0.3 < seuil 0.40 → prédiction "Reste"
+    mock_pipeline.predict_proba.return_value = [[0.70, 0.30]]
+
+    with patch("app.main.load_pipeline", return_value=(mock_pipeline, 0.40)), \
+         patch.dict("os.environ", {"API_KEY": TEST_API_KEY}):
+        with TestClient(app) as c:
+            yield c

tests/test_api.py

@@ -0,0 +1,40 @@
+from tests.conftest import VALID_PAYLOAD, TEST_API_KEY
+
+
+# Tester GET /health
+def test_health_check(client):
+    response = client.get("/health")
+    assert response.status_code == 200
+    assert response.json()["status"] == "ok"
+
+
+# Tester POST /predict avec données valides
+def test_predict_valid(client):
+    response = client.post(
+        "/predict",
+        json=VALID_PAYLOAD,
+        headers={"X-API-Key": TEST_API_KEY},
+    )
+    assert response.status_code == 200
+    body = response.json()
+    assert "label" in body
+    assert body["label"] in ("Reste", "Quitte")
+    assert "probabilite" in body
+    assert 0.0 <= body["probabilite"] <= 1.0
+
+
+# Tester POST /predict avec données invalides
+def test_predict_invalid_data(client):
+    invalid_payload = {"age": 999, "genre": 99}  # hors bornes + champs manquants
+    response = client.post(
+        "/predict",
+        json=invalid_payload,
+        headers={"X-API-Key": TEST_API_KEY},
+    )
+    assert response.status_code == 422  # Pydantic validation error
+
+
+# Tester POST /predict sans API Key → 401
+def test_predict_no_api_key(client):
+    response = client.post("/predict", json=VALID_PAYLOAD)
+    assert response.status_code == 401