fix distribution fact for SLES4SAP (#71559)

b6b238a fixed the SLES4SAP detection, which was at this time ok.
Sadly Suse changed with SLES 15 the /etc/os-release file, so the above
change will no longer work.

This commit updates the SLES4SAP detection regarding
https://www.suse.com/support/kb/doc/?id=000019341.

The symlink realpath is matched with endswith, because in SLES 12+ the
link target is SLES_SAP.prod, but in SLES 11 the link target is
SUSE_SLES_SAP.prod.

changelogs/fragments/71559-fix-distribution-fact-sles4sap.yaml

@@ -0,0 +1,2 @@
+bugfixes:
+  - facts - fix distribution fact for SLES4SAP (https://github.com/ansible/ansible/pull/71559).

lib/ansible/module_utils/facts/system/distribution.py

@@ -271,10 +271,6 @@ class DistributionFiles:
                     else:
                         release = "0"  # no minor number, so it is the first release
                     suse_facts['distribution_release'] = release
-                # Starting with SLES4SAP12 SP3 NAME reports 'SLES' instead of 'SLES_SAP'
-                # According to SuSe Support (SR101182877871) we should use the CPE_NAME to detect SLES4SAP
-                if re.search("^CPE_NAME=.*sles_sap.*$", line):
-                    suse_facts['distribution'] = 'SLES_SAP'
         elif path == '/etc/SuSE-release':
             if 'open' in data.lower():
                 data = data.splitlines()
@@ -297,6 +293,10 @@ class DistributionFiles:
                         suse_facts['distribution_release'] = release.group(1)
                         suse_facts['distribution_version'] = collected_facts['distribution_version'] + '.' + release.group(1)
 
+        # See https://www.suse.com/support/kb/doc/?id=000019341 for SLES for SAP
+        if os.path.islink('/etc/products.d/baseproduct') and os.path.realpath('/etc/products.d/baseproduct').endswith('SLES_SAP.prod'):
+            suse_facts['distribution'] = 'SLES_SAP'
+
         return True, suse_facts
 
     def parse_distribution_file_Debian(self, name, data, path, collected_facts):

test/units/module_utils/facts/system/distribution/fixtures/sles4sap_12_sp2.json

@@ -1,24 +0,0 @@
-{
-    "name": "SLES4SAP 12 SP2",
-    "input": {
-        "/etc/SuSE-release": "SUSE Linux Enterprise Server 12 (x86_64)\nVERSION = 12\nPATCHLEVEL = 2\n# This file is deprecated and will be removed in a future service pack or release.\n# Please check /etc/os-release for details about this release.",
-        "/etc/os-release": "NAME=\"SLES_SAP\"\nVERSION=\"12-SP2\"\nVERSION_ID=\"12.2\"\nPRETTY_NAME=\"SUSE Linux Enterprise Server for SAP Applications 12 SP2\"\nID=\"sles_sap\"\nANSI_COLOR=\"0;32\"\nCPE_NAME=\"cpe:/o:suse:sles_sap:12:sp2\""
-    },
-    "platform.dist": ["SuSE", "12", "x86_64"],
-    "distro": {
-        "codename": "",
-        "id": "sles",
-        "name": "SUSE Linux Enterprise Server",
-        "version": "12.2",
-        "version_best": "12.2",
-        "os_release_info": {},
-        "lsb_release_info": {}
-    },
-    "result": {
-        "distribution": "SLES_SAP",
-        "distribution_major_version": "12",
-        "distribution_release": "2",
-        "os_family": "Suse",
-        "distribution_version": "12.2"
-    }
-}

test/units/module_utils/facts/system/distribution/fixtures/sles4sap_12_sp3.json

@@ -1,24 +0,0 @@
-{
-    "name": "SLES4SAP 12 SP3",
-    "input": {
-        "/etc/SuSE-release": "SUSE Linux Enterprise Server 12 (x86_64)VERSION = 12PATCHLEVEL = 3\n# This file is deprecated and will be removed in a future service pack or release.\n# Please check /etc/os-release for details about this release.",
-        "/etc/os-release": "NAME=\"SLES\"\nVERSION=\"12-SP3\"\nVERSION_ID=\"12.3\"\nPRETTY_NAME=\"SUSE Linux Enterprise Server 12 SP3\"\nID=\"sles\"\nANSI_COLOR=\"0;32\"\nCPE_NAME=\"cpe:/o:suse:sles_sap:12:sp3\""
-    },
-    "platform.dist": ["SuSE", "12", "x86_64"],
-    "distro": {
-        "codename": "",
-        "id": "sles",
-        "name": "SUSE Linux Enterprise Server",
-        "version": "12.3",
-        "version_best": "12.3",
-        "os_release_info": {},
-        "lsb_release_info": {}
-    },
-    "result": {
-        "distribution": "SLES_SAP",
-        "distribution_major_version": "12",
-        "distribution_release": "3",
-        "os_family": "Suse",
-        "distribution_version": "12.3"
-    }
-}

test/units/module_utils/facts/system/distribution/test_distribution_sles4sap.py

@@ -0,0 +1,33 @@
+# -*- coding: utf-8 -*-
+# Copyright: (c) 2020 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+import pytest
+
+from ansible.module_utils.facts.system.distribution import DistributionFiles
+
+
+@pytest.mark.parametrize('realpath', ('SUSE_SLES_SAP.prod', 'SLES_SAP.prod'))
+def test_distribution_sles4sap_suse_sles_sap(mock_module, mocker, realpath):
+    mocker.patch('os.path.islink', return_value=True)
+    mocker.patch('os.path.realpath', return_value='/etc/products.d/' + realpath)
+
+    test_input = {
+        'name': 'SUSE',
+        'path': '',
+        'data': 'suse',
+        'collected_facts': None,
+    }
+
+    test_result = (
+        True,
+        {
+            'distribution': 'SLES_SAP',
+        }
+    )
+
+    distribution = DistributionFiles(module=mock_module())
+    assert test_result == distribution.parse_distribution_file_SUSE(**test_input)