[thredds] FeatureDatasetFactoryManager, Aggregations, And NetcdfFileCache

• To: "thredds@xxxxxxxxxxxxxxxx" <thredds@xxxxxxxxxxxxxxxx>
• Subject: [thredds] FeatureDatasetFactoryManager, Aggregations, And NetcdfFileCache
• From: Sean Cowan <SCowan@xxxxxxxxxxxxxx>
• Date: Tue, 7 May 2013 17:06:22 -0400

We are running into an odd situation involving the FeatureDatasetFactoryManager 
and aggregate ncml datasets relevant to the NetcdfFileCache. With the cache 
active, subsequent attempts to get an aggregate ncml wrapped by a 
FeatureDataset results in the factory manager being unable to properly 
determine the factory for the aggregation.

We receive the following error on subsequent attempts to load the aggregation 
from the FeatureDatasetFactoryManager:

Table TopScalars/PsuedoStructure(time) featureType Station: lat/lon/time coord 
not found
**Failed to find FeatureDatasetFactory for= wqbawagg datatype=STATION

(we also get the same error for datatype=ANY_POINT; the aggregation being used 
is a time series).
I confirmed with OPENDAP that the coordinates are in the dataset, and as I said 
that the first time loading the aggregation is successful; just the subsequent 
attempts to load it fail.

Here is the example aggregation that was tested with (use SOS access to see the 
exception returned, it is a custom message - not what the manager returns):
http://oos.soest.hawaii.edu/thredds/idd/wqb.html?dataset=WQBAWagg

Turning off the NetcdfFileCache solves the issue, however, we would prefer to 
work with the cache on (having it completely off isn't really an option) .

Any help with this would be greatly appreciated.

-----------
Sean M. Cowan
Software Engineer
RPS ASA
55 Village Square Drive
South Kingstown  RI  02879-8248  USA
Tel: +1 (401) 789-6224 ext 378    Fax: +1 (401) 789-1932