[PR #7533/2a5e7c33 backport][stable-8] Add test fqdn_valid (#7567)

Add test fqdn_valid (#7533)

* Add test fqdn_valid

* Add integration test fqdn_valid

* Add changelogs 7533-add-test-fqdn_valid

* Fix changelogs filename 7533-add-test-fqdn_valid.yml

* Add runme.* to install PyPI package fqdn and run the test.

* Remove changelog. New tests are documented by their version_added + short_description.

* Guarded import fqdn.

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update tests/integration/targets/test_fqdn_valid/aliases

Co-authored-by: Felix Fontein <felix@fontein.de>

* Add tests/fqdn_valid.py maintained by vbotka.

* Fix integration. Add explicit collections to test_fqdn_valid

* Fix integration. Remove unused import ansible.errors

* Fix PEP8 E275

* Fix E402 module level import not at top of file.

* Fix E275 missing whitespace after keyword

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/test/fqdn_valid.py

Co-authored-by: Felix Fontein <felix@fontein.de>

---------

Co-authored-by: Felix Fontein <felix@fontein.de>
(cherry picked from commit 2a5e7c33df)

Co-authored-by: Vladimir Botka <vbotka@gmail.com>

plugins/test/fqdn_valid.py

@@ -0,0 +1,103 @@
+# Copyright (c) 2023, Vladimir Botka <vbotka@gmail.com>
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from ansible.errors import AnsibleError
+from ansible.module_utils.six import raise_from
+
+try:
+    from fqdn import FQDN
+except ImportError as imp_exc:
+    ANOTHER_LIBRARY_IMPORT_ERROR = imp_exc
+else:
+    ANOTHER_LIBRARY_IMPORT_ERROR = None
+
+
+DOCUMENTATION = '''
+  name: fqdn_valid
+  short_description: Validates fully-qualified domain names against RFC 1123
+  version_added: 8.1.0
+  author: Vladimir Botka (@vbotka)
+  requirements:
+  - fqdn>=1.5.1 (PyPI)
+  description:
+    - This test validates Fully Qualified Domain Names (FQDNs)
+      conforming to the Internet Engineering Task Force specification
+      RFC 1123 and RFC 952.
+    - The design intent is to validate that a string would be
+      traditionally acceptable as a public Internet hostname to
+      RFC-conforming software, which is a strict subset of the logic
+      in modern web browsers like Mozilla Firefox and Chromium that
+      determines whether make a DNS lookup.
+    - Certificate Authorities like Let's Encrypt run a narrower set of
+      string validation logic to determine validity for issuance. This
+      test is not intended to achieve functional parity with CA
+      issuance.
+    - Single label names are allowed by default (O(min_labels=1)).
+  options:
+    _input:
+      description: Name of the host.
+      type: str
+      required: true
+    min_labels:
+      description: Required minimum of labels, separated by period.
+      default: 1
+      type: int
+      required: false
+    allow_underscores:
+      description: Allow underscore characters.
+      default: false
+      type: bool
+      required: false
+'''
+
+EXAMPLES = '''
+- name: Make sure that hostname is valid
+  ansible.builtin.assert:
+    that: hostname is community.general.fqdn_valid
+
+- name: Make sure that hostname is at least 3 labels long (a.b.c)
+  ansible.builtin.assert:
+    that: hostname is community.general.fqdn_valid(min_labels=3)
+
+- name: Make sure that hostname is at least 2 labels long (a.b). Allow '_'
+  ansible.builtin.assert:
+    that: hostname is community.general.fqdn_valid(min_labels=2, allow_underscores=True)
+'''
+
+RETURN = '''
+  _value:
+    description: Whether the name is valid.
+    type: bool
+'''
+
+
+def fqdn_valid(name, min_labels=1, allow_underscores=False):
+    """
+    Example:
+      - 'srv.example.com' is community.general.fqdn_valid
+      - 'foo_bar.example.com' is community.general.fqdn_valid(allow_underscores=True)
+    """
+
+    if ANOTHER_LIBRARY_IMPORT_ERROR:
+        raise_from(
+            AnsibleError('Python package fqdn must be installed to use this test.'),
+            ANOTHER_LIBRARY_IMPORT_ERROR
+        )
+
+    fobj = FQDN(name, min_labels=min_labels, allow_underscores=allow_underscores)
+    return (fobj.is_valid)
+
+
+class TestModule(object):
+    ''' Ansible test hostname validity.
+        https://pypi.org/project/fqdn/
+    '''
+
+    def tests(self):
+        return {
+            'fqdn_valid': fqdn_valid,
+        }