1. A method implemented at least in part by a computer, the method comprising: discovering one or more target data sources from which to obtain data; generating a data structure that indicates chunks of the data to obtain from the one or more target data sources; generating a query from a template, the query including values derived from the data structure, the values serving to indicate a chunk of the data; submitting the query to one or more of the one or more target data sources; receiving a response to the query, the response including the chunk of the data; and storing the chunk of the data in a local data store.