Add a fact to select --evacuate or --drain based on your OCP version

Closes #3070

2 files changed, 17 insertions, 0 deletions

diff --git a/roles/openshift_facts/library/openshift_facts.py b/roles/openshift_facts/library/openshift_facts.py
index 6baf9d016..10e30f1c4 100755
--- a/roles/openshift_facts/library/openshift_facts.py
+++ b/roles/openshift_facts/library/openshift_facts.py
@@ -867,6 +867,20 @@ def set_deployment_facts_if_unset(facts):
     return facts
 
 
+def set_evacuate_or_drain_option(facts):
+    """OCP before 1.5/3.5 used '--evacuate'. As of 1.5/3.5 OCP uses
+'--drain'. Let's make that a fact for easy reference later.
+    """
+    if facts['common']['version_gte_3_5_or_1_5']:
+        # New-style
+        facts['common']['evacuate_or_drain'] = '--drain'
+    else:
+        # Old-style
+        facts['common']['evacuate_or_drain'] = '--evacuate'
+
+    return facts
+
+
 def set_version_facts_if_unset(facts):
     """ Set version facts. This currently includes common.version and
         common.version_gte_3_1_or_1_1.
@@ -1898,6 +1912,7 @@ class OpenShiftFacts(object):
         facts = build_controller_args(facts)
         facts = build_api_server_args(facts)
         facts = set_version_facts_if_unset(facts)
+        facts = set_evacuate_or_drain_option(facts)
         facts = set_dnsmasq_facts_if_unset(facts)
         facts = set_manageiq_facts_if_unset(facts)
         facts = set_aggregate_facts(facts)
diff --git a/roles/openshift_node/README.md b/roles/openshift_node/README.md
index 616f44c1d..b69b60c1d 100644
--- a/roles/openshift_node/README.md
+++ b/roles/openshift_node/README.md
@@ -47,6 +47,8 @@ oadm manage-node --drain ${NODE}
 oadm manage-node --schedulable=true ${NODE}
 ````
 
+> If you are using version less than 1.5/3.5 you must replace `--drain` with `--evacuate`.
+
 
 TODO