[#7257] factor up the common index_id method
diff --git a/Allura/allura/lib/search.py b/Allura/allura/lib/search.py
index 2a80113..89daac4 100644
--- a/Allura/allura/lib/search.py
+++ b/Allura/allura/lib/search.py
@@ -46,7 +46,11 @@
 
         Used for SOLR ID, shortlinks, and possibly elsewhere.
         """
-        raise NotImplementedError
+        id = '%s.%s#%s' % (
+            self.__class__.__module__,
+            self.__class__.__name__,
+            self._id)
+        return id.replace('.', '/')
 
     def index(self):
         """
diff --git a/Allura/allura/model/artifact.py b/Allura/allura/model/artifact.py
index 143c44a..659d04c 100644
--- a/Allura/allura/model/artifact.py
+++ b/Allura/allura/model/artifact.py
@@ -77,7 +77,7 @@
                 log.debug('Not updating mod_date')
             if c.project and not skip_last_updated:
                 c.project.last_updated = datetime.utcnow()
- 
+
     type_s = 'Generic Artifact'
 
     # Artifact base schema
@@ -297,13 +297,6 @@
         else:
             return self.app_config.load()(self.project, self.app_config)
 
-    def index_id(self):
-        id = '%s.%s#%s' % (
-            self.__class__.__module__,
-            self.__class__.__name__,
-            self._id)
-        return id.replace('.', '/')
-
     def index(self):
         project = self.project
         return dict(
diff --git a/Allura/allura/model/project.py b/Allura/allura/model/project.py
index 3182ded..431d986 100644
--- a/Allura/allura/model/project.py
+++ b/Allura/allura/model/project.py
@@ -991,13 +991,6 @@
         else:
             return 'busy'
 
-    def index_id(self):
-        id = '%s.%s#%s' % (
-            self.__class__.__module__,
-            self.__class__.__name__,
-            self._id)
-        return id.replace('.', '/')
-
     def index(self):
         provider = plugin.ProjectRegistrationProvider.get()
         try: