API1: write datasetUpdateHandler

[cellisco]

code: opendataplus/apps/datasets/dataset_update_handler.js

Main dataset module that evals all datasets defined in the platform to see if then need updating and orchestrates executing the update...

Main generic function that tracks the last time the dataset was checked and the frequency its is supposed to be checked and if it needs to be checked, orchestrates calling the dataset handlers.

• check frequency
• if time to update
  • execute dataset's checkForUpdate module
  • if true
    • execute dataset's "handleDatasetUpdate" module
    • for each document in the dataset
      • if document has not been updated longer than datasetParameter.documentRetentionTime
        • execute dataset's handleExpiredDocuments module for that document