feat: add health monitoring endpoint

apps/health/tests/test_views.py

@@ -0,0 +1,103 @@
+from __future__ import annotations
+
+import re
+
+import pytest
+
+
+def _mock_checks(monkeypatch, **overrides):
+    payloads = {
+        "db": {"status": "ok", "latency_ms": 1.0},
+        "cache": {"status": "ok", "latency_ms": 1.0},
+        "celery": {"status": "ok"},
+        "backup": {"status": "ok"},
+    }
+    payloads.update(overrides)
+
+    monkeypatch.setattr("apps.health.views.check_db", lambda: payloads["db"])
+    monkeypatch.setattr("apps.health.views.check_cache", lambda: payloads["cache"])
+    monkeypatch.setattr("apps.health.views.check_celery", lambda: payloads["celery"])
+    monkeypatch.setattr("apps.health.views.check_backup", lambda: payloads["backup"])
+
+
+@pytest.mark.django_db
+def test_healthy(client, monkeypatch):
+    _mock_checks(monkeypatch)
+
+    response = client.get("/health/")
+
+    assert response.status_code == 200
+    assert response.json()["status"] == "ok"
+
+
+@pytest.mark.django_db
+def test_degraded_celery(client, monkeypatch):
+    _mock_checks(monkeypatch, celery={"status": "fail", "detail": "broker down"})
+
+    response = client.get("/health/")
+
+    assert response.status_code == 200
+    assert response.json()["status"] == "degraded"
+
+
+@pytest.mark.django_db
+def test_degraded_backup(client, monkeypatch):
+    _mock_checks(monkeypatch, backup={"status": "fail", "detail": "backup missing"})
+
+    response = client.get("/health/")
+
+    assert response.status_code == 200
+    assert response.json()["status"] == "degraded"
+
+
+@pytest.mark.django_db
+def test_unhealthy_db(client, monkeypatch):
+    _mock_checks(monkeypatch, db={"status": "fail", "detail": "db down"})
+
+    response = client.get("/health/")
+
+    assert response.status_code == 503
+    assert response.json()["status"] == "unhealthy"
+
+
+@pytest.mark.django_db
+def test_unhealthy_cache(client, monkeypatch):
+    _mock_checks(monkeypatch, cache={"status": "fail", "detail": "cache down"})
+
+    response = client.get("/health/")
+
+    assert response.status_code == 503
+    assert response.json()["status"] == "unhealthy"
+
+
+@pytest.mark.django_db
+def test_response_shape(client, monkeypatch):
+    _mock_checks(monkeypatch)
+
+    payload = client.get("/health/").json()
+
+    assert set(payload) == {"status", "version", "checks", "timestamp"}
+    assert set(payload["version"]) == {"git_sha", "build"}
+    assert set(payload["checks"]) == {"db", "cache", "celery", "backup"}
+    assert re.fullmatch(r"\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z", payload["timestamp"])
+
+
+@pytest.mark.django_db
+def test_version_fields(client, monkeypatch):
+    _mock_checks(monkeypatch)
+    monkeypatch.setenv("GIT_SHA", "59cc1c4")
+    monkeypatch.setenv("BUILD_ID", "build-20260306-59cc1c4")
+
+    payload = client.get("/health/").json()
+
+    assert payload["version"]["git_sha"]
+    assert payload["version"]["build"]
+
+
+@pytest.mark.django_db
+def test_no_cache_headers(client, monkeypatch):
+    _mock_checks(monkeypatch)
+
+    response = client.get("/health/")
+
+    assert "no-cache" in response["Cache-Control"]