From 1b8aa423a63f53936cbcdfe9a5f6201088383227 Mon Sep 17 00:00:00 2001
From: Simon Li <spli@dundee.ac.uk>
Date: Fri, 23 Sep 2016 18:20:41 +0100
Subject: [PATCH] Return non-zero error code if no hosts match

This is useful when running ansible-playbook automatically, since failure to mat
ch a host may mean there's an incorrect hostname or groupname somewhere
---
 ansible/ansible.cfg                           |  3 ++
 .../callback/error_if_no_hosts_match.py       | 39 +++++++++++++++++++
 2 files changed, 42 insertions(+)
 create mode 100644 ansible/plugins/callback/error_if_no_hosts_match.py

diff --git a/ansible/ansible.cfg b/ansible/ansible.cfg
index 62a1ef2cb..e7b3f64ac 100644
--- a/ansible/ansible.cfg
+++ b/ansible/ansible.cfg
@@ -26,6 +26,9 @@ inventory_ignore_extensions = ~, .orig, .bak, .ini, .retry, .pyc, .pyo, .html, .
 # Helps determine what's running slowly
 callback_whitelist = profile_tasks
 
+# Additional plugins
+callback_plugins = ./plugins/callback
+
 # Performance options
 [ssh_connection]
 pipelining = True
diff --git a/ansible/plugins/callback/error_if_no_hosts_match.py b/ansible/plugins/callback/error_if_no_hosts_match.py
new file mode 100644
index 000000000..554ffba5b
--- /dev/null
+++ b/ansible/plugins/callback/error_if_no_hosts_match.py
@@ -0,0 +1,39 @@
+# https://gist.github.com/jjshoe/ace3070906e5bc5cc432
+# https://github.com/ansible/ansible/pull/14742
+# https://github.com/ansible/ansible/issues/14693
+
+# Make coding more python3-ish
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+import os
+import time
+import sys
+
+from ansible.plugins.callback import CallbackBase
+
+
+class CallbackModule(CallbackBase):
+    """
+    This callback module exits with non-zero if no hosts match
+    """
+    CALLBACK_VERSION = 2.0
+    CALLBACK_TYPE = 'aggregate'
+    CALLBACK_NAME = 'no_hosts_match_exit_non_zero'
+    CALLBACK_NEEDS_WHITELIST = False
+
+    def __init__(self):
+        super(CallbackModule, self).__init__()
+
+    def playbook_on_stats(self, stats):
+        found_stats = False
+
+        for key in ['ok', 'failures', 'dark', 'changed', 'skipped']:
+            if len(getattr(stats, key)) > 0:
+                found_stats = True
+                break
+
+        if found_stats == False:
+            print('ERROR: No hosts matched')
+            sys.exit(10)