convert dot-less CentOS versions to X.999

CentOS Stream doesn't do dot releases, so it always has the major
version in the version_id field of os-release.
Our code, in multiple places, expects versions in the form X.Y and
doesn't cope well when given only X.
The value "999" is taken arbitrarily, with the sole assumption that it
will be always higher than any RHEL release, as CentOS Stream is ahead
of RHEL.

See https://issues.redhat.com/browse/CS-1757 for further discussion and
alternative numbering options.

repos/system_upgrade/common/actors/ipuworkflowconfig/libraries/ipuworkflowconfig.py

@@ -50,12 +50,16 @@ def get_os_release(path):
     try:
         with open(path) as f:
             data = dict(l.strip().split('=', 1) for l in f.readlines() if '=' in l)
+            release_id = data.get('ID', '').strip('"')
+            version_id = data.get('VERSION_ID', '').strip('"')
+            if release_id == 'centos' and '.' not in version_id:
+                version_id = "{}.999".format(version_id)
             return OSRelease(
-                release_id=data.get('ID', '').strip('"'),
+                release_id=release_id,
                 name=data.get('NAME', '').strip('"'),
                 pretty_name=data.get('PRETTY_NAME', '').strip('"'),
                 version=data.get('VERSION', '').strip('"'),
-                version_id=data.get('VERSION_ID', '').strip('"'),
+                version_id=version_id,
                 variant=data.get('VARIANT', '').strip('"') or None,
                 variant_id=data.get('VARIANT_ID', '').strip('"') or None
             )

repos/system_upgrade/common/actors/ipuworkflowconfig/tests/files/os-release-stream8

@@ -0,0 +1,13 @@
+NAME="CentOS Stream"
+VERSION="8"
+ID="centos"
+ID_LIKE="rhel fedora"
+VERSION_ID="8"
+PLATFORM_ID="platform:el8"
+PRETTY_NAME="CentOS Stream 8"
+ANSI_COLOR="0;31"
+CPE_NAME="cpe:/o:centos:centos:8"
+HOME_URL="https://centos.org/"
+BUG_REPORT_URL="https://bugzilla.redhat.com/"
+REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux 8"
+REDHAT_SUPPORT_PRODUCT_VERSION="CentOS Stream"

repos/system_upgrade/common/actors/ipuworkflowconfig/tests/test_ipuworkflowconfig.py

@@ -63,6 +63,17 @@ def test_get_os_release_info(monkeypatch):
         ipuworkflowconfig.get_os_release(os.path.join(CUR_DIR, 'files/non-existent-file'))
 
 
+def test_get_os_release_info_centos_stream(monkeypatch):
+    expected = OSRelease(
+        release_id='centos',
+        name='CentOS Stream',
+        pretty_name='CentOS Stream 8',
+        version='8',
+        version_id='8.999'
+    )
+    assert expected == ipuworkflowconfig.get_os_release(os.path.join(CUR_DIR, 'files/os-release-stream8'))
+
+
 def test_get_booted_kernel(monkeypatch):
     monkeypatch.setattr(ipuworkflowconfig, 'run', lambda x: {'stdout': '4.14.0-100.8.2.el7a.x86_64\n'})
     assert ipuworkflowconfig.get_booted_kernel() == '4.14.0-100.8.2.el7a.x86_64'