TemplateHelper: Expire metadata cache on FileMonitor event

2 files changed, 15 insertions, 4 deletions

diff --git a/src/lib/Bcfg2/Server/Plugins/TemplateHelper.py b/src/lib/Bcfg2/Server/Plugins/TemplateHelper.py
index cec2de297..09f3130ca 100644
--- a/src/lib/Bcfg2/Server/Plugins/TemplateHelper.py
+++ b/src/lib/Bcfg2/Server/Plugins/TemplateHelper.py
@@ -22,9 +22,10 @@ def safe_module_name(module):
 class HelperModule(Debuggable):
     """ Representation of a TemplateHelper module """
 
-    def __init__(self, name):
+    def __init__(self, name, core):
         Debuggable.__init__(self)
         self.name = name
+        self.core = core
 
         #: The name of the module as used by get_additional_data().
         #: the name of the file with .py stripped off.
@@ -51,6 +52,10 @@ class HelperModule(Debuggable):
         if event and event.code2str() not in ['exists', 'changed', 'created']:
             return
 
+        # expire the metadata cache, because the module might have changed
+        if self.core.metadata_cache_mode in ['cautious', 'aggressive']:
+            self.core.metadata_cache.expire()
+
         try:
             module = imp.load_source(safe_module_name(self._module_name),
                                      self.name)
@@ -107,7 +112,6 @@ class TemplateHelper(Plugin, Connector, DirectoryBacked, TemplateDataProvider):
     __author__ = 'chris.a.st.pierre@gmail.com'
     ignore = re.compile(r'^(\.#.*|.*~|\..*\.(sw[px])|.*\.py[co])$')
     patterns = MODULE_RE
-    __child__ = HelperModule
 
     def __init__(self, core):
         Plugin.__init__(self, core)
@@ -115,6 +119,10 @@ class TemplateHelper(Plugin, Connector, DirectoryBacked, TemplateDataProvider):
         DirectoryBacked.__init__(self, self.data)
         TemplateDataProvider.__init__(self)
 
+        # The HelperModule needs access to the core, so we have to construct
+        # it manually and add the custom argument.
+        self.__child__ = lambda fname: HelperModule(fname, core)
+
     def get_additional_data(self, _):
         return dict([(h._module_name, h)  # pylint: disable=W0212
                      for h in self.entries.values()])
diff --git a/testsuite/Testsrc/Testlib/TestServer/TestPlugins/TestTemplateHelper.py b/testsuite/Testsrc/Testlib/TestServer/TestPlugins/TestTemplateHelper.py
index 128d6cae5..6f5ee18ba 100644
--- a/testsuite/Testsrc/Testlib/TestServer/TestPlugins/TestTemplateHelper.py
+++ b/testsuite/Testsrc/Testlib/TestServer/TestPlugins/TestTemplateHelper.py
@@ -22,10 +22,13 @@ class TestHelperModule(Bcfg2TestCase):
     test_obj = HelperModule
     path = os.path.join(datastore, "test.py")
 
-    def get_obj(self, path=None):
+    def get_obj(self, path=None, core=None):
         if path is None:
             path = self.path
-        return self.test_obj(path)
+        if core is None:
+            core = Mock()
+            core.metadata_cache_mode = 'none'
+        return self.test_obj(path, core)
 
     def test__init(self):
         hm = self.get_obj()