1 files changed, 94 insertions, 0 deletions
diff --git a/src/lib/Bcfg2/Server/Lint/TemplateHelper.py b/src/lib/Bcfg2/Server/Lint/TemplateHelper.py
new file mode 100644
index 000000000..fbd5a2893
--- /dev/null
+++ b/src/lib/Bcfg2/Server/Lint/TemplateHelper.py
@@ -0,0 +1,94 @@
+""" ``bcfg2-lint`` plugin for :ref:`TemplateHelper
+<server-plugins-connectors-templatehelper>` """
+
+import sys
+import imp
+from Bcfg2.Server.Lint import ServerPlugin
+from Bcfg2.Server.Plugins.TemplateHelper import HelperModule, MODULE_RE, \
+    safe_module_name
+
+
+class TemplateHelper(ServerPlugin):
+    """ ``bcfg2-lint`` plugin to ensure that all :ref:`TemplateHelper
+    <server-plugins-connectors-templatehelper>` modules are valid.
+    This can check for:
+
+    * A TemplateHelper module that cannot be imported due to syntax or
+      other compile-time errors;
+    * A TemplateHelper module that does not have an ``__export__``
+      attribute, or whose ``__export__`` is not a list;
+    * Bogus symbols listed in ``__export__``, including symbols that
+      don't exist, that are reserved, or that start with underscores.
+    """
+
+    def __init__(self, *args, **kwargs):
+        ServerPlugin.__init__(self, *args, **kwargs)
+        self.reserved_keywords = dir(HelperModule("foo.py"))
+        self.reserved_defaults = \
+            self.core.plugins['TemplateHelper'].reserved_defaults
+
+    def Run(self):
+        for helper in self.core.plugins['TemplateHelper'].entries.values():
+            if self.HandlesFile(helper.name):
+                self.check_helper(helper.name)
+
+    def check_helper(self, helper):
+        """ Check a single helper module.
+
+        :param helper: The filename of the helper module
+        :type helper: string
+        """
+        module_name = MODULE_RE.search(helper).group(1)
+
+        try:
+            module = imp.load_source(safe_module_name(module_name), helper)
+        except:  # pylint: disable=W0702
+            err = sys.exc_info()[1]
+            self.LintError("templatehelper-import-error",
+                           "Failed to import %s: %s" %
+                           (helper, err))
+            return
+
+        if not hasattr(module, "__export__"):
+            self.LintError("templatehelper-no-export",
+                           "%s has no __export__ list" % helper)
+            return
+        elif not isinstance(module.__export__, list):
+            self.LintError("templatehelper-nonlist-export",
+                           "__export__ is not a list in %s" % helper)
+            return
+
+        for sym in module.__export__:
+            if not hasattr(module, sym):
+                self.LintError("templatehelper-nonexistent-export",
+                               "%s: exported symbol %s does not exist" %
+                               (helper, sym))
+            elif sym in self.reserved_keywords:
+                self.LintError("templatehelper-reserved-export",
+                               "%s: exported symbol %s is reserved" %
+                               (helper, sym))
+            elif sym.startswith("_"):
+                self.LintError("templatehelper-underscore-export",
+                               "%s: exported symbol %s starts with underscore"
+                               % (helper, sym))
+            if sym in getattr(module, "__default__", []):
+                self.LintError("templatehelper-export-and-default",
+                               "%s: %s is listed in both __default__ and "
+                               "__export__" % (helper, sym))
+
+        for sym in getattr(module, "__default__", []):
+            if sym in self.reserved_defaults:
+                self.LintError("templatehelper-reserved-default",
+                               "%s: default symbol %s is reserved" %
+                               (helper, sym))
+
+    @classmethod
+    def Errors(cls):
+        return {"templatehelper-import-error": "error",
+                "templatehelper-no-export": "error",
+                "templatehelper-nonlist-export": "error",
+                "templatehelper-nonexistent-export": "error",
+                "templatehelper-reserved-export": "error",
+                "templatehelper-reserved-default": "error",
+                "templatehelper-underscore-export": "warning",
+                "templatehelper-export-and-default": "warning"}