R/util.R

In yutannihilation/wunderlistr: R interface to Wunderlist API

# Utilities

wndr_api <- function(verb, path, id = NULL, ...) {
  if (!is.null(id)) path <- build_path_with_id(path, id)

  res <- httr::VERB(verb = verb,
             url = "https://a.wunderlist.com/",
             config = httr::add_headers(
               `X-Client-ID` = wndr_key,
               `X-Access-Token` = wndr_access_token()
             ),
             path = path,
             ...,
             encode = "json")

  httr::stop_for_status(res)

  if (!httr::has_content(res)) return(NULL)

  # If the resonse is JSON format, parse it by ourselve with simplifying options.
  if (res$headers$`content-type` == "application/json") {
    body <- httr::content(res, as = "text", encoding = "UTF-8")
    jsonlite::fromJSON(body, simplifyVector = TRUE)
  } else {
    httr::content(res)
  }

}


wndr_delete_common <- function(id, revision, path) {
  wndr_api(verb = "DELETE",
           path = path,
           id   = id,
           query = list(
             revision = revision
           ))
}

wndr_get_by_id_or_list_or_task <- function(id, task_id, list_id, path, ...) {
  query <- create_scalar_list(id      = id,
                              task_id = task_id,
                              list_id = list_id)
  # add additional parameters
  other_query <- purrr::compact(list(...))
  query <- modifyList(query, other_query)

  if (!is.null(id)) {
    wndr_api(verb = "GET",
             path = path,
             id   = id)
  } else {
    wndr_api(verb = "GET",
             path = path,
             query = query)
  }
}

build_path_with_id <- function(path, id) {
  if (!purrr::is_scalar_numeric(id) && !purrr::is_scalar_character(id)) {
    stop("id must be a single numeric or character")
  }

  paste(path, id, sep = "/")
}

# Returns a scalar list when only one parameter is not NULL
#
# e.g.) crate_scalar_list(a = 1, b = NULL) -> OK
#       crate_scalar_list(a = 1, b = 2) -> NG
#       crate_scalar_list(a = NULL, b = NULL) -> NG
create_scalar_list <- function(...) {
  params <- list(...)
  compact_list <- purrr::compact(params)

  if (!purrr::is_scalar_list(compact_list)) {
    param_names <- names(params)
    last_index <- length(param_names)
    stop(sprintf("Please specify either one of %s or %s",
                 paste(param_names[-last_index], collapse = ", "), param_names[last_index]))
  }

  return(compact_list)
}