Optionally rotate old data

Introduces a 'rotation' parameter in config.js that will remove
entries older than n days from the datasets, resulting in a rolling
view of bug activity.

README.rst

@@ -35,3 +35,7 @@ to generate data for. "height" is an optional parameter detailing
 the size of the graph (230 pixels is the default value). "title"
 is an optional parameter for the name of the project in the index
 page.
+
+You can also optionally specify a 'rotation' parameter. Entries older
+than the value (in days) will be removed from the dataset, resulting
+in a rolling view of bug activity.

bugdaystats.py

@@ -41,7 +41,7 @@ def create_files(templatepath, outputpath, projects):
             template.stream(project=project).dump(projectfile)
 
 
-def update_stats(outputpath, project_name):
+def update_stats(outputpath, project_name, rotation):
 
     now = int(time.time())
     records = []
@@ -55,6 +55,10 @@ def update_stats(outputpath, project_name):
         json_data = json.load(data_file)
         data_file.close()
         for record in json_data['records']:
+            if rotation:
+                if (now - record['date']) > (rotation * 24 * 60 * 60):
+                    print "skip"
+                    continue
             records.append(record)
     except IOError:
         pass
@@ -157,6 +161,7 @@ if __name__ == '__main__':
     with open(configpath, 'r') as configfile:
         config = json.load(configfile)
     projects = config['projects']
+    rotation = config.get('rotation')
 
     # Create files in output directory, if needed
     create_files(templatepath, outputpath, projects)
@@ -166,4 +171,4 @@ if __name__ == '__main__':
                                             cachedir)
 
     for p in projects:
-        update_stats(outputpath, p['project'])
+        update_stats(outputpath, p['project'], rotation)

config.js.sample

@@ -9,5 +9,6 @@
         { "project": "swift" },
         { "project": "openstack-manuals", "title": "Manuals" },
         { "project": "tempest" }
-    ]
+    ],
+    "rotation": 2
 }