Detecting Conflicts in Put()

WORK IN PROGRESS

+------------+--------------+--------------+---------------+--------------+------------------+
| LUID       | Comparison With Existing Data                              | No Existing Data |
+            +--------------+--------------+---------------+--------------+                  +
|            | *Newer*      | *Older*      | *Equal*       | *Unknown*    |                  |
+------------+--------------+--------------+---------------+--------------+------------------+
| Known      | Put (1)      | Conflict (2) | Skip (3)      | Conflict (4) | Put (5)          |
+------------+--------------+--------------+---------------+--------------+------------------+
| Unknown    | Conflict (2) | Conflict (2) | Skip (3)      | Conflict (4) | Put (5)          |
+------------+--------------+--------------+---------------+--------------+------------------+

Pseudo-code

   1 def put(self, data, overwrite, LUID=None):
   2     DataProvider.TwoWay.put(self, data, overwrite, LUID)
   3     if overwrite and LUID:
   4         LUID = self._replace_data(LUID, data)
   5     else:
   6         if LUID and self._data_exists(LUID):
   7             oldData = self._get_data(LUID)
   8             comp = data.compare(oldData)
   9             #Possibility 1: If LUID != None (i.e this is a modification/update of a 
  10             #previous sync, and we are newer, the go ahead an put the data
  11             if LUID != None and comp == conduit.datatypes.COMPARISON_NEWER:
  12                 LUID = self._replace_data(LUID, data)
  13             #Possibility 3: We are the same, so return either rid
  14             elif comp == conduit.datatypes.COMPARISON_EQUAL:
  15                 return oldData.get_rid()
  16             #Possibility 2, 4: All that remains are conflicts
  17             else:
  18                 raise Exceptions.SynchronizeConflictError(comp, data, oldData)
  19         else:
  20             #Possibility 5:
  21             LUID = self._put_data(data)
  22 
  23     #now return the rid
  24     if not LUID:
  25         raise Exceptions.SyncronizeError("Error putting/updating data")
  26     else:
  27         return self._get_data(LUID).get_rid()

Projects/Conduit/WritingADataProvider/GeneralPutInstructions (last edited 2013-11-21 21:30:17 by WilliamJonMcCann)