ds.listOpals calls the internal DataSHIELD function getOpals() which identifies all Opal objects in the analytic environment.
ds.listOpals calls the internal DataSHIELD function getOpals() which identifies all Opal objects in the analytic environment. If there are no Opal servers in the analytic environment ds.listOpalsIreminds the user that they have to login to a valid set of Opal login objects, if they wish to use DataSHIELD. If there is only one set of Opals, ds.listOpals copies that one set and names the copy 'default.opals'. This default set will then be used by default by all subsequent calls to client-side functions. If there is more than one set of Opals in the analytic environment, ds.listOpals tells the user that they can either explicitly specify the Opals to be used by each client-side function by providing an explicit "datasources=" argument for each call, or can alternatively use the ds.setDefaultOpals function to specify a default set of Opals to be used by all client-side calls unless over-ruled by the 'datasources=' argument.
Lists all of the sets of Opals currently found in the analytic environment and advises the user how best to respond depending whether there are zero, one or multiple Opals detected.
Burton, PR. 28/9/16