# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1395533721 -3600
# Node ID a1d7a02f19cb3ade6f30d210dc8f5b33f5a15237
# Parent  08edd667312226cdb70052884f9608ea75c71c5e
Added period length restrictions on displayed calendars.

diff -r 08edd6673122 -r a1d7a02f19cb EventAggregatorSupport/View.py
--- a/EventAggregatorSupport/View.py	Sun Mar 23 01:14:04 2014 +0100
+++ b/EventAggregatorSupport/View.py	Sun Mar 23 01:15:21 2014 +0100
@@ -6,6 +6,7 @@
     @license: GNU GPL (v2 or later), see COPYING.txt for details.
 """
 
+from DateSupport import Date
 from EventAggregatorSupport.Filter import getCalendarPeriod, getEventsInPeriod, \
                                           getCoverage, getCoverageScale
 from EventAggregatorSupport.Locations import getMapsPage, getLocationsPage, Location
@@ -140,7 +141,7 @@
 
         self.first = first
         self.last = last
-        self.duration = abs(last - first) + 1
+        self.initDuration()
 
         if self.calendar_name:
 
@@ -156,6 +157,28 @@
             self.previous_set_end = last.update(-self.duration)
             self.next_set_end = last.update(self.duration)
 
+    def initDuration(self):
+
+        "Limit the duration of the calendar to prevent excessive output."
+
+        request = self.page.request
+
+        self.duration = abs(self.last - self.first) + 1
+
+        # Limit to the specified number of units.
+
+        limit = int(getattr(request.cfg, "event_aggregator_max_duration", 20))
+
+        if self.duration > limit:
+            if isinstance(self.first, Date):
+                self.last = self.first.day_update(limit - 1)
+            else:
+                self.last = self.first.month_update(limit - 1)
+
+            self.calendar_start = self.calendar_start or self.first
+            self.calendar_end = self.calendar_end or self.last
+            self.duration = limit
+
     def getIdentifier(self):
 
         "Return a unique identifier to be used to refer to this view."
diff -r 08edd6673122 -r a1d7a02f19cb TO_DO.txt
--- a/TO_DO.txt	Sun Mar 23 01:14:04 2014 +0100
+++ b/TO_DO.txt	Sun Mar 23 01:15:21 2014 +0100
@@ -1,9 +1,3 @@
-View Extents
-------------
-
-It should not be possible for an event to provoke an undesirably large
-calendar extent, thus creating work for the server and for browsers.
-
 Navigation Controls
 -------------------