Merge ~nick-moffitt/content-cache-charm:hack-around-upgrade-bug into content-cache-charm:master

[Nick Moffitt]

Apply workaround for https://github.com/cmars/nrpe-external-master-interface/issues/12

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Stuart Bishop (stub)]

Ok, since this was tested, but would have been more correct in a @hook('upgrade-charm') handler.

review: Approve

[Nick Moffitt (nick-moffitt)]

It actually is in @@ -25,6 +25,14 @@ def upgrade_charm(): so we're all good here.

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision f9ea69395561e59898f7fe9d54d8097bf2965b04

diff --git a/reactive/content_cache.py b/reactive/content_cache.py
index e137694..934563d 100644
--- a/reactive/content_cache.py
+++ b/reactive/content_cache.py
@@ -25,6 +25,14 @@ def upgrade_charm():
     reactive.clear_flag('content_cache.nginx.configured')
     reactive.clear_flag('nagios-nrpe.configured')
 
+    # Work around for
+    # https://github.com/cmars/nrpe-external-master-interface/issues/12
+    n = reactive.endpoint_from_name('nrpe-external-master')
+    if n is None:
+        hookenv.log('no nrpe-external-master relation to force')
+    else:
+        reactive.set_flag('nrpe-external-master.available')
+
 
 @reactive.when_not('content_cache.installed')
 def install():