Converts a server-side R object into a character class

Converts the input object into a character class. This function is based on the native R function as.character.

ds.asCharacter(x.name = NULL, newobj = NULL, datasources = NULL)

Arguments

x.name

a character string providing the name of the input object to be coerced to class character.

newobj

a character string that provides the name for the output object that is stored on the data servers. Default ascharacter.newobj.

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.asCharacter returns the object converted into a class character that is written to the server-side. Also, two validity messages are returned to the client-side indicating the name of the newobj which has been created in each data source and if it is in a valid form.

Details

Server function called: asCharacterDS

Author

DataSHIELD Development Team

Examples

if (FALSE) { # \dontrun{
  ## Version 6, for version 5 see the Wiki
  
  # 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") 
  
  # Converting the R object into a class character
  ds.asCharacter(x.name = "D$LAB_TSC",
                 newobj = "char.obj",
                 datasources = connections[1]) #only the first Opal server is used ("study1")
                 
  # Clear the Datashield R sessions and logout                 
  datashield.logout(connections) 
  
} # }