shinyauthr

The package provides two main modules consisting of a UI component and a Server component:

1. Login Module: loginUI() and loginServer() handle user credentials.
2. Logout Module: logoutUI() and logoutServer() handle session termination.

The credentials object

When loginServer() is called, it returns a reactive list containing two elements:

• user_auth: A boolean (TRUE if authenticated, FALSE otherwise).
• info: A row of data from your provided data frame associated with the authenticated user (or NULL if not authenticated).

Workflow Pattern

• Use req(credentials()$user_auth) inside your reactives, renders, and observers to ensure code only executes after a successful login.
• The logoutServer() module should be passed a reactive trigger based on the user_auth status to automatically show/hide the logout button.

# Minimal usage pattern
credentials <- shinyauthr::loginServer(
  id = "login",
  data = user_base,
  user_col = user,
  pwd_col = password,
  log_out = reactive(logout_init())
)

logout_init <- shinyauthr::logoutServer(
  id = "logout",
  active = reactive(credentials()$user_auth)
)

To avoid repeated logins, you can implement cookie-based authentication by providing cookie_setter and cookie_getter functions to loginServer().

Requirements:

1. cookie_setter: A function accepting (user, sessionid) that saves the session to a persistent store (e.g., a database).
2. cookie_getter: A function that returns a data.frame containing valid user and sessionid columns.

loginServer parameters for cookies:

• cookie_logins: Set to TRUE.
• sessionid_col: The name of the column in your data containing session IDs.
• cookie_getter: Your custom getter function.
• cookie_setter: Your custom setter function.

# Example setup for cookie-based login
credentials <- shinyauthr::loginServer(
  id = "login",
  data = user_base,
  user_col = user,
  pwd_col = password,
  cookie_logins = TRUE,
  sessionid_col = sessionid,
  cookie_getter = get_sessionids_from_db,
  cookie_setter = add_sessionid_to_db,
  log_out = reactive(logout_init())
)

To add authentication, define a data frame containing user credentials, add the loginUI and logoutUI to your UI, and initialize the loginServer and logoutServer in your server function.

library(shiny)

# 1. Define user data
user_base <- tibble::tibble(
  user = c("user1", "user2"),
  password = c("pass1", "pass2"),
  permissions = c("admin", "standard"),
  name = c("User One", "User Two")
)

ui <- fluidPage(
  div(class = "pull-right", shinyauthr::logoutUI(id = "logout")),
  shinyauthr::loginUI(id = "login"),
  tableOutput("user_table")
)

server <- function(input, output, session) {
  # 2. Initialize login server
  credentials <- shinyauthr::loginServer(
    id = "login",
    data = user_base,
    user_col = user,
    pwd_col = password,
    log_out = reactive(logout_init())
  )

  # 3. Initialize logout server
  logout_init <- shinyauthr::logoutServer(
    id = "logout",
    active = reactive(credentials()$user_auth)
  )

  # 4. Use credentials to protect content
  output$user_table <- renderTable({
    req(credentials()$user_auth)
    credentials()$info
  })
}

shinyApp(ui = ui, server = server)