R Programming By Example

Encapsulating multiple databases with a storage layer

Now that we have developed our Database interface and our CSVFiles implementation of such an interface, we are ready to develop the next layer of abstraction, our Storage class. It will be implemented with R6.

As you can see, the Storage constructor implemented in the initialize function receives a settings object which will be the full centralized settings file we have been mentioning and will use the storage/read, storage/write, and storage/table_names parts to create various database instances through the use of the database_factory() function we explained before. In the case of the read_db attribute, it will be a single Database implementation that will be used to read data. In the ...