move pytest settings to pyproject and actually make use of pytest-doc…

…ker-compose for testing locally

pyproject.toml

@@ -51,8 +51,13 @@ dev = [
     "types-mock>=5.1.0",
     "bumpver>=2023.1129",
     "git-cliff>=2.0.4",
+    "tenacity>=8.2.3",
 ]
 
+[tool.pytest.ini_options]
+addopts = "'--docker-compose' './tests/docker-compose.yml' '--docker-compose-no-build' '--use-running-containers'"
+DJANGO_SETTINGS_MODULE = "test_project.settings"
+
 [tool.ruff]
 line-length = 88
 target-version = "py311"

tests/conftest.py

@@ -1 +1,53 @@
-pytest_plugins = ['docker_compose']
+import subprocess
+
+import pytest
+from tenacity import retry, wait_fixed, stop_after_attempt, RetryError
+
+
+pytest_plugins = ["docker_compose"]
+
+
+def pytest_addoption(parser):
+    parser.addoption(
+        "--ci",
+        action="store_true",
+        default=False,
+        help="Run tests as if in a CI environment",
+    )
+
+
+def wait_for_postgres_from_compose(session_scoped_container_getter):
+    """Wait for the postgres container to be ready."""
+    container = session_scoped_container_getter.get("postgres")
+    is_ready = "accepting connections" in container.execute(
+        ["pg_isready", "-h", "localhost", "-U", "postgres"]
+    )
+    assert is_ready
+
+
+def wait_for_postgres_from_ci():
+    """Wait for the postgres service to be ready."""
+    is_ready = (
+        subprocess.run(["pg_isready", "-h", "localhost", "-U", "postgres"]).returncode
+        == 0
+    )
+    assert is_ready
+
+
+@pytest.fixture(scope="session")
+@retry(wait=wait_fixed(2), stop=stop_after_attempt(3))
+def wait_for_postgres(request, session_scoped_container_getter):
+    """Wait for postgres to be ready.
+
+    Chooses a different strategy depending on whether the tests are running with containerized postgres locally
+    or a postgres service in a CI environment.
+    """
+    if request.config.getoption("--ci"):
+        return wait_for_postgres_from_ci()
+    else:
+        return wait_for_postgres_from_compose(session_scoped_container_getter)
+
+
+@pytest.fixture(scope="session")
+def django_db_setup(wait_for_postgres, django_db_setup):
+    pass