R/auth.R

In hdar: 'REST' API Client for Accessing Data on 'WEkEO HDA V2'

#' @title Auth Class
#'
#' @description
#' Authorization
#'
#' @importFrom R6 R6Class
#' @importFrom magrittr %>%
#' @export
Auth <- R6::R6Class("Auth", # nolint: object_name_linter.
  public = list(

    #' @description
    #' This function initializes a new instance of the `Auth` class with the specified parameters.
    #'
    #' @param user A character string representing the username for authentication.
    #' @param password A character string representing the password for authentication.
    #'
    #' @return An instance of the `Auth` class.
    #' @export
    initialize = function(user = NULL, password = NULL) {
      private$user <- user
      private$password <- password
    },

    #' @description
    #' This function retrieves a previously generated token.
    #'
    #' @return A character string representing the retrieved token.
    #' @export
    token = function() {
      if (is.null(private$token_value)) {
        self$get_token()
      }
      private$token_value
    },

    #' @description
    #' This function generates a unique token for authentication or other purposes.
    #'
    #' @return A character string representing the generated token.
    #' @export
    get_token = function() {
      url <- paste0(private$apiUrl, "/gettoken")

      params <- list(
        "username" = private$user,
        "password" = private$password
      )
      req <- httr2::request(url) %>%
        httr2::req_method("POST") %>%
        httr2::req_body_json(params)

      try(req %>% httr2::req_perform())
      resp <- httr2::last_response()

      if (resp$status_code == 200) {
        resp_body <- resp %>% httr2::resp_body_json()
        private$token_value <- resp_body$access_token
        return(private$token_value)
      }

      private$token_value <- NULL
      stop(resp$detail)
    }
  ),
  private = list(
    apiUrl = "https://gateway.prod.wekeo2.eu/hda-broker",
    token_value = NULL,
    user = NULL,
    password = NULL
  )
)