Gets the metadata associated with a variable held on the server

This function gets the metadata of a variable stored on the server.

ds.metadata(x = NULL, datasources = NULL)

Arguments

x

a character string specifying the name of the object.

datasources

a list of DSConnection-class objects obtained after login. If the datasources argument is not specified the default set of connections will be used: see datashield.connections_default.

Value

ds.metadata returns to the client-side the metadata of associated to an object held at the server.

Details

Server function metadataDS is called examines the attributes associated with the variable which are non-disclosive.

Author

Stuart Wheater, DataSHIELD Development Team

Examples

if (FALSE) { # \dontrun{

  # connecting to the Opal servers

  require('DSI')
  require('DSOpal')
  require('dsBaseClient')

  builder <- DSI::newDSLoginBuilder()
  builder$append(server = "study1", 
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM1", driver = "OpalDriver")
  builder$append(server = "study2", 
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM2", driver = "OpalDriver")
  builder$append(server = "study3",
                 url = "http://192.168.56.100:8080/", 
                 user = "administrator", password = "datashield_test&", 
                 table = "CNSIM.CNSIM3", driver = "OpalDriver")
  logindata <- builder$build()
  
  connections <- DSI::datashield.login(logins = logindata, assign = TRUE, symbol = "D") 
  
  # Example 1: Get the metadata associated with variable 'D'
  ds.metadata(x = 'D$LAB_TSC', datasources = connections)

  # clear the Datashield R sessions and logout
  DSI::datashield.logout(connections)
} # }