dns: warn if mail_domain is an IP, instead of checking DNS

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -144,6 +144,9 @@ def dns_cmd_options(parser):
 
 def dns_cmd(args, out):
     """Check DNS entries and optionally generate dns zone file."""
+    if is_valid_ipv4(args.config.mail_domain):
+        print(f"[WARNING] {args.config.mail_domain} is not a domain, skipping DNS checks.")
+        return 0
     ssh_host = args.ssh_host if args.ssh_host else args.config.mail_domain
     sshexec = get_sshexec(ssh_host, verbose=args.verbose)
     tls_cert_mode = args.config.tls_cert_mode

cmdeploy/src/cmdeploy/tests/test_cmdeploy.py

@@ -39,6 +39,14 @@ class TestCmdline:
         out, err = capsys.readouterr()
         assert "deleting config file" in out.lower()
 
+    def test_dns_skip_on_ip(self, capsys, tmp_path, monkeypatch):
+        monkeypatch.delenv("CHATMAIL_INI", raising=False)
+        inipath = tmp_path / "chatmail.ini"
+        assert main(["init", "--config", str(inipath), "1.3.3.7"]) == 0
+        assert main(["dns", "--config", str(inipath)]) == 0
+        out, err = capsys.readouterr()
+        assert out == "[WARNING] 1.3.3.7 is not a domain, skipping DNS checks.\n"
+
 
 def test_www_folder(example_config, tmp_path):
     reporoot = importlib.resources.files(__package__).joinpath("../../../../").resolve()