How to implement Basic Authentication in R-plumber?

Question

I have an API built in R-Plumber. I want to add basic authentication to this API(i.e. username and password). How can I do that?

Answer 1

I have figured out how to use the req object provided in R Plumber to implement the Basic Authentication.

We will access Basic Authentication parameters from req$HTTP_AUTHORIZATION, then use base64decode to Decode them into username:password format and then split the string to retrieve the username and password.

Further, write a function to validate whether the user credentials are valid.

# Define the authentication logic

auth_basic <- function(username, password) {
  # Check if the username and password are valid
  valid_credentials <- username == "hello" && password == "user123"
  
  # Return TRUE if the credentials are valid, FALSE otherwise
  return(valid_credentials)
}


#* @get /secured
function(req, res) {
  
  library(base64enc)
  encoded_string <- req$HTTP_AUTHORIZATION  
  encoded_string <- gsub("Basic ", "",encoded_string)
  decoded_string <- rawToChar(base64decode(what = encoded_string))
  username <- strsplit(decoded_string, ":")[[1]][1]
  password <- strsplit(decoded_string, ":")[[1]][2]
  
  cat("decoded string: ", decoded_string, "username: ", username, "password: ", password)
  
  if(is.na(username) | is.na(password)){
    return("credentials not provided")
  }
  
  if(auth_basic(username, password) == FALSE){
    return("invalid credentials")
  }
  
  return("This is a secured endpoint")

}