Add flags to allow to restrict DB modifications.

Author: stefanseefeld

roundup/backends/rdbms_common.py

@@ -513,6 +513,9 @@ def update_class(self, spec, old_spec, force=0):
             # no changes
             return 0
 
+        if not self.config.RDBMS_ALLOW_ALTER:
+            raise DatabaseError(_('ALTER operation disallowed: %r -> %r.'%(old_spec, new_spec)))
+
         logger = logging.getLogger('roundup.hyperdb')
         logger.info('update_class %s'%spec.classname)
 
@@ -737,6 +740,10 @@ def drop_multilink_table_indexes(self, classname, ml):
     def create_class(self, spec):
         """ Create a database table according to the given spec.
         """
+
+        if not self.config.RDBMS_ALLOW_CREATE:
+            raise DatabaseError(_('CREATE operation disallowed: "%s".'%spec.classname))
+
         cols, mls = self.create_class_table(spec)
         self.create_journal_table(spec)
 
@@ -749,6 +756,10 @@ def drop_class(self, cn, spec):
 
             Drop the journal and multilink tables too.
         """
+
+        if not self.config.RDBMS_ALLOW_DROP:
+            raise DatabaseError(_('DROP operation disallowed: "%s".'%cn))
+
         properties = spec[1]
         # figure the multilinks
         mls = []

roundup/configuration.py

@@ -610,6 +610,12 @@ def str2value(self, value):
             "Only used in SQLite connections."),
         (IntegerNumberOption, 'cache_size', '100',
             "Size of the node cache (in elements)"),
+        (BooleanOption, "allow_create", "yes",
+            "Setting this option to 'no' protects the database against table creations."),
+        (BooleanOption, "allow_alter", "yes",
+            "Setting this option to 'no' protects the database against table alterations."),
+        (BooleanOption, "allow_drop", "yes",
+            "Setting this option to 'no' protects the database against table drops."),
         (NullableOption, 'template', '',
             "Name of the PostgreSQL template for database creation.\n"
             "For database creation the template used has to match\n"