arr-init/tests/network-namespace.nix

{ pkgs, lib, self }:
pkgs.testers.runNixOSTest {
  name = "arr-init-network-namespace";
  nodes.machine = { pkgs, lib, ... }: {
    imports = [ self.nixosModules.default ];
    system.stateVersion = "24.11";
    virtualisation.memorySize = 2048;
    environment.systemPackages = with pkgs; [ curl jq gnugrep iproute2 ];

    # Create the network namespace with loopback
    systemd.services.create-netns = {
      description = "Create test network namespace";
      wantedBy = [ "multi-user.target" ];
      before = [ "mock-sonarr.service" ];
      serviceConfig = {
        Type = "oneshot";
        RemainAfterExit = true;
        ExecStart = "${pkgs.iproute2}/bin/ip netns add test-ns";
        ExecStartPost = "${pkgs.iproute2}/bin/ip netns exec test-ns ${pkgs.iproute2}/bin/ip link set lo up";
        ExecStop = "${pkgs.iproute2}/bin/ip netns delete test-ns";
      };
    };

    # Mock Servarr API running inside the namespace
    systemd.services.mock-sonarr = let
      mockScript = pkgs.writeScript "mock-sonarr-ns.py" ''
        import json
        from http.server import HTTPServer, BaseHTTPRequestHandler
        from urllib.parse import urlparse

        DOWNLOAD_CLIENTS = []
        ROOT_FOLDERS = []

        class MockArr(BaseHTTPRequestHandler):
            def _respond(self, code=200, body=b"", content_type="application/json"):
                self.send_response(code)
                self.send_header("Content-Type", content_type)
                self.end_headers()
                self.wfile.write(body if isinstance(body, bytes) else body.encode())

            def do_GET(self):
                path = urlparse(self.path).path
                if path == "/api/v3/system/status":
                    self._respond(200, json.dumps({"version": "4.0.0"}).encode())
                elif path == "/api/v3/downloadclient":
                    self._respond(200, json.dumps(DOWNLOAD_CLIENTS).encode())
                elif path == "/api/v3/rootfolder":
                    self._respond(200, json.dumps(ROOT_FOLDERS).encode())
                else:
                    self._respond(200, b"{}")

            def do_POST(self):
                path = urlparse(self.path).path
                content_length = int(self.headers.get("Content-Length", 0))
                body = self.rfile.read(content_length)
                if "/rootfolder" in path:
                    data = json.loads(body)
                    data["id"] = len(ROOT_FOLDERS) + 1
                    ROOT_FOLDERS.append(data)
                    self._respond(201, json.dumps(data).encode())
                else:
                    self._respond(200, b"{}")

            def log_message(self, format, *args):
                pass

        HTTPServer(("0.0.0.0", 8989), MockArr).serve_forever()
      '';
    in {
      description = "Mock Sonarr API in network namespace";
      after = [ "create-netns.service" ];
      requires = [ "create-netns.service" ];
      wantedBy = [ "multi-user.target" ];
      serviceConfig = {
        ExecStart = "${pkgs.python3}/bin/python3 ${mockScript}";
        Type = "simple";
        NetworkNamespacePath = "/run/netns/test-ns";
      };
    };

    # Pre-seed config.xml
    systemd.tmpfiles.rules = [
      "d /var/lib/mock-sonarr 0755 root root -"
      "f /var/lib/mock-sonarr/config.xml 0644 root root - <Config><ApiKey>test-api-key-ns</ApiKey></Config>"
      "d /media/tv 0755 root root -"
    ];

    services.arrInit.sonarr = {
      enable = true;
      serviceName = "mock-sonarr";
      dataDir = "/var/lib/mock-sonarr";
      port = 8989;
      healthChecks = false;
      networkNamespacePath = "/run/netns/test-ns";
      networkNamespaceService = "create-netns";
      rootFolders = [ "/media/tv" ];
    };
  };
  testScript = ''
    start_all()
    machine.wait_for_unit("create-netns.service")
    machine.wait_for_unit("mock-sonarr.service")

    with subtest("Unit has correct namespace configuration"):
        unit_content = machine.succeed("systemctl cat mock-sonarr-init.service")
        assert "NetworkNamespacePath=/run/netns/test-ns" in unit_content, \
            f"Expected NetworkNamespacePath in unit, got:\n{unit_content}"
        assert "create-netns.service" in unit_content, \
            f"Expected create-netns.service dependency in unit, got:\n{unit_content}"

    with subtest("Mock API is reachable only inside namespace"):
        # From the default namespace, the mock should NOT be reachable
        machine.fail("curl -sf --connect-timeout 2 http://127.0.0.1:8989/api/v3/system/status")
        # From inside the namespace, it should be reachable (wait for mock to start listening)
        machine.wait_until_succeeds(
            "ip netns exec test-ns curl -sf http://127.0.0.1:8989/api/v3/system/status "
            "-H 'X-Api-Key: test-api-key-ns'",
            timeout=30,
        )

    with subtest("Init service completes inside namespace"):
        machine.succeed("systemctl restart mock-sonarr-init.service")
        machine.wait_for_unit("mock-sonarr-init.service", timeout=30)
        exit_code = machine.succeed(
            "systemctl show mock-sonarr-init.service --property=ExecMainStatus | cut -d= -f2"
        ).strip()
        assert exit_code == "0", f"Expected exit code 0, got {exit_code}"

    with subtest("Root folder was provisioned via namespace"):
        result = machine.succeed(
            "ip netns exec test-ns curl -sf http://127.0.0.1:8989/api/v3/rootfolder "
            "-H 'X-Api-Key: test-api-key-ns' | jq -e '.[] | select(.path == \"/media/tv\")'"
        )
  '';
}