test: mock dns calls (#1922)

Add fixture to disallow dns lookups by
default in a common utility function.

6 files changed, 36 insertions, 1 deletions

diff --git a/tests/unittests/config/test_apt_source_v3.py b/tests/unittests/config/test_apt_source_v3.py
index 5bb87385..8d7ba5dc 100644
--- a/tests/unittests/config/test_apt_source_v3.py
+++ b/tests/unittests/config/test_apt_source_v3.py
@@ -14,6 +14,8 @@ import tempfile
 from unittest import TestCase, mock
 from unittest.mock import call
 
+import pytest
+
 from cloudinit import gpg, subp, util
 from cloudinit.config import cc_apt_configure
 from tests.unittests import helpers as t_help
@@ -955,6 +957,7 @@ class TestAptSourceConfig(t_help.FilesystemMockingTestCase):
         self.assertEqual(mirrors["PRIMARY"], pmir)
         self.assertEqual(mirrors["SECURITY"], smir)
 
+    @pytest.mark.allow_dns_lookup
     def test_apt_v3_url_resolvable(self):
         """test_apt_v3_url_resolvable - Test resolving urls"""
 
diff --git a/tests/unittests/conftest.py b/tests/unittests/conftest.py
index 1ab17e8b..a3daaf22 100644
--- a/tests/unittests/conftest.py
+++ b/tests/unittests/conftest.py
@@ -2,6 +2,7 @@ import builtins
 import glob
 import os
 from pathlib import Path
+from unittest import mock
 
 import pytest
 
@@ -58,6 +59,21 @@ def fake_filesystem(mocker, tmpdir):
             mocker.patch.object(mod, f, trap_func)
 
 
+@pytest.fixture(autouse=True)
+def disable_dns_lookup(request):
+    if "allow_dns_lookup" in request.keywords:
+        yield
+        return
+
+    def side_effect(args, *other_args, **kwargs):
+        raise AssertionError("Unexpectedly used util.is_resolvable")
+
+    with mock.patch(
+        "cloudinit.util.is_resolvable", side_effect=side_effect, autospec=True
+    ):
+        yield
+
+
 PYTEST_VERSION_TUPLE = tuple(map(int, pytest.__version__.split(".")))
 
 if PYTEST_VERSION_TUPLE < (3, 9, 0):
diff --git a/tests/unittests/sources/test_aliyun.py b/tests/unittests/sources/test_aliyun.py
index 6ceaf8f4..f95923a4 100644
--- a/tests/unittests/sources/test_aliyun.py
+++ b/tests/unittests/sources/test_aliyun.py
@@ -161,8 +161,9 @@ class TestAliYunDatasource(test_helpers.ResponsesTestCase):
             self.default_metadata["hostname"], self.ds.get_hostname().hostname
         )
 
+    @mock.patch("cloudinit.sources.DataSourceEc2.util.is_resolvable")
     @mock.patch("cloudinit.sources.DataSourceAliYun._is_aliyun")
-    def test_with_mock_server(self, m_is_aliyun):
+    def test_with_mock_server(self, m_is_aliyun, m_resolv):
         m_is_aliyun.return_value = True
         self.regist_default_server()
         ret = self.ds.get_data()
diff --git a/tests/unittests/sources/test_ec2.py b/tests/unittests/sources/test_ec2.py
index 4dd7c497..3fe525e3 100644
--- a/tests/unittests/sources/test_ec2.py
+++ b/tests/unittests/sources/test_ec2.py
@@ -5,6 +5,7 @@ import json
 import threading
 from unittest import mock
 
+import pytest
 import requests
 import responses
 
@@ -223,6 +224,12 @@ TAGS_METADATA_2021_03_23: dict = {
 }
 
 
+@pytest.fixture(autouse=True)
+def disable_is_resolvable():
+    with mock.patch("cloudinit.sources.DataSourceEc2.util.is_resolvable"):
+        yield
+
+
 def _register_ssh_keys(rfunc, base_url, keys_data):
     """handle ssh key inconsistencies.
 
diff --git a/tests/unittests/sources/test_openstack.py b/tests/unittests/sources/test_openstack.py
index 8bcecae7..75a0dda1 100644
--- a/tests/unittests/sources/test_openstack.py
+++ b/tests/unittests/sources/test_openstack.py
@@ -10,6 +10,7 @@ import re
 from io import StringIO
 from urllib.parse import urlparse
 
+import pytest
 import responses
 
 from cloudinit import helpers, settings, util
@@ -76,6 +77,12 @@ EC2_VERSIONS = [
 MOCK_PATH = "cloudinit.sources.DataSourceOpenStack."
 
 
+@pytest.fixture(autouse=True)
+def mock_is_resolvable():
+    with mock.patch(f"{MOCK_PATH}util.is_resolvable"):
+        yield
+
+
 # TODO _register_uris should leverage test_ec2.register_mock_metaserver.
 def _register_uris(version, ec2_files, ec2_meta, os_files, *, responses_mock):
     """Registers a set of url patterns into responses that will mimic the
diff --git a/tox.ini b/tox.ini
index dd7973b7..3b668bc0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -318,3 +318,4 @@ markers =
     ubuntu: this test should run on Ubuntu
     unstable: skip this test because it is flakey
     user_data: the user data to be passed to the test instance
+	allow_dns_lookup: disable autochecking for host network configuration