"""Unit coverage for the fail-closed guest-local container engine (#392).""" from __future__ import annotations import unittest from dataclasses import dataclass from pathlib import Path from types import SimpleNamespace from typing import cast from unittest.mock import patch from bot_bottle.backend.macos_container import nested_containers from bot_bottle.backend.macos_container import launch as launch_mod from bot_bottle.backend.macos_container.bottle_plan import MacosContainerBottlePlan class _Bottle: def __init__(self, results: list[SimpleNamespace]) -> None: self.results = results self.commands: list[str] = [] def exec(self, command: str) -> SimpleNamespace: self.commands.append(command) return self.results.pop(0) def _result(returncode: int, *, stdout: str = "", stderr: str = "") -> SimpleNamespace: return SimpleNamespace(returncode=returncode, stdout=stdout, stderr=stderr) @dataclass(frozen=True) class _AgentProvision: image: str @dataclass(frozen=True) class _Spec: image_policy: str = "build" @dataclass(frozen=True) class _Plan: slug: str image: str dockerfile_path: str nested_containers: bool agent_provision: _AgentProvision spec: _Spec = _Spec() def _base_image_only(ref: str) -> bool: """Only the un-derived agent image is cached on the host.""" return not ref.endswith(nested_containers.IMAGE_SUFFIX) def _plan(**kwargs: object) -> MacosContainerBottlePlan: return cast(MacosContainerBottlePlan, cast(object, _Plan(**kwargs))) # type: ignore[arg-type] class TestNestedContainersStart(unittest.TestCase): def test_bootstraps_then_waits_for_guest_local_service(self) -> None: bottle = _Bottle([_result(0), _result(1), _result(0)]) with patch.object(nested_containers.time, "sleep"): nested_containers.start(bottle) self.assertIn("nested-containers-init", bottle.commands[0]) self.assertEqual(2, bottle.commands.count("docker info >/dev/null 2>&1")) def test_bootstrap_failure_is_fatal_without_privilege_fallback(self) -> None: bottle = _Bottle([_result(1, stderr="slirp4netns missing")]) with patch.object(nested_containers, "die", side_effect=RuntimeError) as die: with self.assertRaises(RuntimeError): nested_containers.start(bottle) self.assertIn("slirp4netns missing", die.call_args.args[0]) self.assertEqual(1, len(bottle.commands)) def test_timeout_reports_guest_log(self) -> None: bottle = _Bottle( [_result(0)] + [_result(1) for _ in range(nested_containers.READY_RETRIES)] + [_result(0, stdout="operation not permitted")] ) with patch.object(nested_containers.time, "sleep"), \ patch.object(nested_containers, "die", side_effect=RuntimeError) as die: with self.assertRaises(RuntimeError): nested_containers.start(bottle) self.assertIn("operation not permitted", die.call_args.args[0]) class TestNestedContainersDevices(unittest.TestCase): def test_relaxes_only_the_two_blocked_device_nodes_as_root(self) -> None: calls: list[tuple[str, list[str]]] = [] def record(name: str, argv: list[str]) -> None: calls.append((name, argv)) nested_containers.prepare_guest_devices("bottle-1", record) self.assertEqual(1, len(calls)) name, argv = calls[0] self.assertEqual("bottle-1", name) self.assertIn("chmod 0666 /dev/fuse /dev/net/tun", argv[-1]) class TestNestedContainersImage(unittest.TestCase): def test_layers_tooling_without_changing_base_image(self) -> None: calls: list[tuple[str, str, str]] = [] def build(image: str, context: str, *, dockerfile: str) -> None: calls.append((image, context, dockerfile)) text = Path(dockerfile).read_text(encoding="utf-8") self.assertIn("FROM agent:base", text) self.assertIn("aardvark-dns fuse-overlayfs netavark nftables passt podman", text) self.assertIn("USER node", text) self.assertTrue((Path(context) / "nested-containers-init.sh").is_file()) image = nested_containers.build_image("agent:base", build) self.assertEqual("agent:base-nested-containers", image) self.assertEqual("agent:base-nested-containers", calls[0][0]) def test_installs_the_whole_podman_5_networking_stack(self) -> None: """Each missing piece fails at a different, misleading layer: no pasta and nothing starts; no nft and netavark cannot build the bridge that compose expects; no aardvark-dns and DNS inside nested containers fails while everything else looks healthy. Image pulls keep working throughout, which is what made these read as compat-API bugs.""" seen: list[str] = [] def build(_image: str, _context: str, *, dockerfile: str) -> None: seen.append(Path(dockerfile).read_text(encoding="utf-8")) nested_containers.build_image("agent:base", build) for package in ("podman", "passt", "nftables", "aardvark-dns"): self.assertIn(package, seen[0]) def test_strips_subordinate_ranges_so_podman_avoids_newuidmap(self) -> None: """The single-UID fallback is the entire reason podman works here. A subordinate range would send podman down the newuidmap path, which cannot write a multi-range uid_map without CAP_SYS_ADMIN in an Apple Container guest — the failure that killed the rootless-Docker spike. """ seen: list[str] = [] def build(_image: str, _context: str, *, dockerfile: str) -> None: seen.append(Path(dockerfile).read_text(encoding="utf-8")) nested_containers.build_image("agent:base", build) text = seen[0] self.assertIn("sed -i '/^node:/d' /etc/subuid /etc/subgid", text) self.assertNotIn("subuid", text.replace( "sed -i '/^node:/d' /etc/subuid /etc/subgid", "", )) class TestInitScript(unittest.TestCase): """The bootstrap runs inside the bottle, so its wiring is only checkable here or on a live macOS host.""" def setUp(self) -> None: self.script = ( Path(nested_containers.__file__).with_name("nested-containers-init.sh") .read_text(encoding="utf-8") ) def test_ca_bundle_path_matches_the_backend_constant(self) -> None: from bot_bottle.backend.util import AGENT_CA_BUNDLE self.assertIn(f'CA_BUNDLE="{AGENT_CA_BUNDLE}"', self.script) def test_resolves_the_gateway_address_for_nested_containers(self) -> None: """podman's hosts_file only applies to native `podman run` — the Docker-compat API ignores it, and the agent types `docker`. So the gateway name is resolved here and the *address* goes into the proxy URL; otherwise every nested container dies at "Could not resolve proxy", which reads like broken DNS but is a missing hosts entry.""" self.assertIn('$2 == name { print $1; exit }', self.script) self.assertIn('value.replace(name, ip)', self.script) def test_docker_cli_proxy_config_uses_the_address(self) -> None: """The Docker CLI copies ~/.docker/config.json's proxies block into every container it starts. Being client-side it beats the podman service, so this — not containers.conf — is what decides whether a nested container can reach the proxy.""" block = self.script[self.script.index('"proxies"'):] self.assertIn('"httpProxy": proxy.replace(name, ip)', block) self.assertIn('"httpsProxy": proxy.replace(name, ip)', block) self.assertIn('"noProxy": no_proxy', block) def test_substitutes_the_address_into_the_service_environment(self) -> None: """Covers what the Docker CLI does not stamp: podman's own registry pulls, and containers created through the API by another client.""" launch = self.script[self.script.index("podman system service"):] self.assertNotIn("$GATEWAY_NAME", launch) # substitution precedes it setup = self.script[:self.script.index("podman system service")] self.assertIn("for var in HTTP_PROXY HTTPS_PROXY http_proxy https_proxy", setup) def test_disables_podmans_own_proxy_passthrough(self) -> None: """podman copies the host's proxy vars into every container by default, and that copy overrides the env we set — putting the unresolvable gateway name back and leaving nested containers at "bad address 'bot-bottle-gateway'".""" self.assertIn('"http_proxy=false"', self.script) def test_keeps_the_gateway_name_in_no_proxy(self) -> None: """NO_PROXY is matched against what a client asks for, and code inside a nested container still says bot-bottle-gateway.""" start = self.script.index('for var in ("NO_PROXY"') loop = self.script[start:self.script.index("path = Path(", start)] self.assertIn('entries.append(f"{var}={value}")', loop) self.assertNotIn("replace(name, ip)", loop) self.assertIn('"noProxy": no_proxy', self.script) def test_fails_closed_without_a_gateway_address(self) -> None: self.assertIn('[ -n "$gateway_ip" ] || {', self.script) def test_mounts_and_trusts_the_gateway_ca(self) -> None: """The gateway TLS-intercepts, so without the bundle every HTTPS call from a nested container fails with "unable to get local issuer certificate".""" self.assertIn('volumes=["{ca}:{ca}:ro"]', self.script) for var in ( "SSL_CERT_FILE", "CURL_CA_BUNDLE", "REQUESTS_CA_BUNDLE", "NODE_EXTRA_CA_CERTS", ): self.assertIn(f'f"{var}={{ca}}"', self.script) def test_writes_the_token_bearing_config_unreadable_to_others(self) -> None: """The proxy URL carries the bottle's identity token.""" self.assertIn("path.chmod(0o600)", self.script) class TestGuestEnvironment(unittest.TestCase): def test_disabled_bottle_gets_no_docker_environment(self) -> None: self.assertEqual({}, nested_containers.guest_env(False)) def test_enabled_bottle_uses_only_the_guest_local_socket(self) -> None: env = nested_containers.guest_env(True) self.assertEqual("unix:///tmp/bbp/podman.sock", env["DOCKER_HOST"]) self.assertNotIn("/var/run/docker.sock", " ".join(env.values())) def test_runtime_dir_leaves_room_for_conmons_attach_socket(self) -> None: """podman builds `$XDG_RUNTIME_DIR/libpod/tmp/socket/<64-hex>/attach`, which must fit in sun_path (108 bytes). A descriptive runtime dir blew past it and every attached `docker run` failed with "unable to upgrade to tcp, received 500" while pulls and detached runs looked fine.""" attach = ( nested_containers.guest_env(True)["XDG_RUNTIME_DIR"] + "/libpod/tmp/socket/" + "a" * 64 + "/attach" ) self.assertLessEqual(len(attach), 107, attach) def test_macos_backend_declares_support(self) -> None: from bot_bottle.backend.macos_container.backend import ( MacosContainerBottleBackend, ) self.assertTrue(MacosContainerBottleBackend.supports_nested_containers) class TestBuildOrLoadImages(unittest.TestCase): def test_disabled_bottle_keeps_the_plain_agent_image(self) -> None: plan = _plan( slug="dev-abc", image="agent:base", dockerfile_path="/repo/Dockerfile", nested_containers=False, agent_provision=_AgentProvision("agent:base"), ) with patch.object(launch_mod, "read_committed_image", return_value=None), \ patch.object(launch_mod.container_mod, "build_image"), \ patch.object(launch_mod.nested_containers_mod, "build_image") as derived: images = launch_mod.build_or_load_images(plan) derived.assert_not_called() self.assertEqual("agent:base", images.agent) def test_enabled_bottle_builds_base_then_derived_variant(self) -> None: plan = _plan( slug="dev-abc", image="agent:base", dockerfile_path="/repo/Dockerfile", nested_containers=True, agent_provision=_AgentProvision("agent:base"), ) with patch.object(launch_mod, "read_committed_image", return_value=None), \ patch.object(launch_mod.container_mod, "build_image") as build, \ patch.object( launch_mod.nested_containers_mod, "build_image", return_value="agent:base-nested-containers", ) as derived: images = launch_mod.build_or_load_images(plan) build.assert_called_once_with( "agent:base", launch_mod._REPO_DIR, # pylint: disable=protected-access dockerfile="/repo/Dockerfile", ) derived.assert_called_once_with("agent:base", build) self.assertEqual("agent:base-nested-containers", images.agent) def test_derived_image_layers_onto_a_committed_image(self) -> None: plan = _plan( slug="dev-abc", image="agent:base", dockerfile_path="/repo/Dockerfile", nested_containers=True, agent_provision=_AgentProvision("agent:base"), ) with patch.object( launch_mod, "read_committed_image", return_value="agent:committed", ), \ patch.object(launch_mod.container_mod, "image_exists", return_value=True), \ patch.object(launch_mod.container_mod, "build_image") as build, \ patch.object( launch_mod.nested_containers_mod, "build_image", return_value="agent:committed-nested-containers", ) as derived: images = launch_mod.build_or_load_images(plan) build.assert_not_called() derived.assert_called_once_with("agent:committed", build) self.assertEqual("agent:committed-nested-containers", images.agent) def test_cached_policy_refuses_to_build_the_derived_image(self) -> None: plan = _plan( slug="dev-abc", image="agent:base", dockerfile_path="/repo/Dockerfile", nested_containers=True, agent_provision=_AgentProvision("agent:base"), spec=_Spec(image_policy="cached"), ) with patch.object(launch_mod, "read_committed_image", return_value=None), \ patch.object( launch_mod.container_mod, "image_exists", side_effect=_base_image_only, ), \ patch.object(launch_mod.nested_containers_mod, "build_image") as derived, \ patch.object(launch_mod, "die", side_effect=RuntimeError) as die: with self.assertRaises(RuntimeError): launch_mod.build_or_load_images(plan) derived.assert_not_called() self.assertIn("agent:base-nested-containers", die.call_args.args[0]) if __name__ == "__main__": unittest.main()