datashield.login: Logs in and assigns variables to R
In datashield/opal: Opal R and Datashield utils

Description Usage Arguments Value Author(s) Examples

This function allows for clients to login to opal servers and (optionaly) assign all the data or specific variables from Opal tables to R dataframes. The assigned dataframes (one for each opal server) are named 'D' (by default).

datashield.login(logins = NULL, assign = FALSE, variables = NULL,
  symbol = "D", directory = "~/.ssh",
  username = getOption("datashield.username"),
  password = getOption("datashield.password"),
  opts = getOption("datashield.opts", list()), restore = NULL,
  tibble = FALSE)

`logins`	A dataframe table that holds login details. This table holds five elements required to login to the servers where the data to analyse is stored. The expected column names are 'server' (the server name), 'url' (the opal url), 'user' (the user name or the certificate file path), 'password' (the user password or the private key file path), 'table' (the fully qualified name of the table in opal), 'options' (the SSL options). An additional column 'identifiers' can be specified for identifiers mapping (from Opal 2.0). See also the documentation of the examplar input table `logindata` for details of the login elements.
`assign`	A boolean which tells whether or not data should be assigned from the opal table to R after login into the server(s).
`variables`	Specific variables to assign. If `assign` is set to FALSE this argument is ignored otherwise the specified variables are assigned to R. If no variables are specified (default) the whole opal's table is assigned.
`symbol`	A character, the name of the dataframe to which the opal's table will be assigned after login into the server(s).
`directory`	A character that indicates the location of the key pairs files (certificate and private key). If the default location is the users '.ssh' directory.
`username`	Default user name to be used in case it is not specified in the logins structure.
`password`	Default user password to be used in case it is not specified in the logins structure.
`opts`	Default SSL options to be used in case it is not specified in the logins structure.
`restore`	The workspace name to restore (optional).
`tibble`	Assign table to a tibble (from tidyverse) instead of a plain data.frame.

object(s) of class opal

Gaye, A.

## Not run: 

#### The below examples illustrate an analysises that use test/simulated data ####

# build your data.frame
server <- c("study1", "study2")
url <- c("https://some.opal.host:8443","https://another.opal.host")
user <- c("user1", "datashield-certificate.pem")
password <- c("user1pwd", "datashield-private.pem")
table <- c("store.Dataset","foo.DS")
options <- c("","c(ssl.verifyhost=2,ssl.verifypeer=1)")
logindata <- data.frame(server,url,user,password,table)

# or load the data.frame that contains the login details
data(logindata)

# Example 1: just login (default)
opals <- datashield.login(logins=logindata)

# Example 2: login and assign the whole dataset
opals <- datashield.login(logins=logindata,assign=TRUE)

# Example 3: login and assign specific variable(s)
myvar <- list("LAB_TSC")
opals <- datashield.login(logins=logindata,assign=TRUE,variables=myvar)

## End(Not run)