R/api.R

In shunsambongi/domo: DBI for DOMO

new_api_result <- function(content, path, response) {
  structure(
    list(
      content = content,
      path = path,
      response = response
    ),
    class = "domo_api_result"
  )
}

setOldClass("domo_api_result")

api_result <- function(
  response, path = url_path(response), expected_type = "application/json"
) {
  content <- parse_content(response)
  validate_response(response, content)
  validate_type(response, expected_type, content)
  new_api_result(content, path, response)
}

#' @export
print.domo_api_result <- function(x, ...) {
  method <- x$response$request$method
  path <- x$path
  cat_line("<DOMO: {method} {path}>")
  utils::str(x$content)
  invisible(x)
}

domo_api <- function(
  verb, path, ..., expected_type = "application/json", .envir = parent.frame()
) {
  path <- glue::glue(path, .envir = .envir)
  url <- httr::modify_url("https://api.domo.com", path = path)

  user_agent <- httr::user_agent("https://github.com/shunsambongi/domo")
  config <- rlang::dots_list(...)
  do_request <- function() {
    config <- map_if(config, is_token, as_header)
    resp <- rlang::exec(
      httr::VERB, verb = verb, url = url, user_agent, !!!config
    )
    api_result(resp, path, expected_type)
  }

  withRestarts(do_request(), "refreshed" = do_request)
}

validate_type <- function(response, expected_type, content) {
  if (!is.null(expected_type) && httr::http_type(response) != expected_type) {
    rlang::abort(
      message = glue::glue("API did not return {expected_type}"),
      class = "domo_unexpected_type",
      response = response,
      content = content
    )
  }
  invisible(response)
}

validate_response <- function(response, content) {
  if (!httr::http_error(response)) {
    return(invisible(response))
  }

  status_code <- httr::status_code(response)
  description <- content$error_description %||%
    content$message %||%
    "<no description available>"
  msg <- glue::glue(
    "DOMO API request failed [{status_code}]",
    "{description}",
    .sep = "\n"
  )
  rlang::abort(
    message = msg,
    class = "domo_api_error",
    response = response,
    content = content
  )
}

parse_content <- function(response) {
  type <- httr::http_type(response)
  text <- httr::content(response, "text")
  switch(
    type,
    "application/json" = jsonlite::fromJSON(text, simplifyVector = FALSE),
    "application/octet-stream" = text,
    "text/csv" = vroom::vroom(text, delim = ","),
    {
      rlang::abort(
        message = glue::glue("Cannot parse type {type}"),
        class = "domo_unparseable_type",
        response = response,
        content = text
      )
    }
  )
}


# verbs -------------------------------------------------------------------

GET <- function(path, ..., .envir = parent.frame()) {
  domo_api(verb = "GET", path = path, ..., .envir = .envir)
}

PATCH <- function(path, ..., .envir = parent.frame()) {
  domo_api(verb = "PATCH", path = path, ..., .envir = .envir)
}

POST <- function(path, ..., .envir = parent.frame()) {
  domo_api(verb = "POST", path = path, ..., .envir = .envir)
}

PUT <- function(path, ..., .envir = parent.frame()) {
  domo_api(verb = "PUT", path = path, ..., .envir = .envir)
}

DELETE <- function(path, ..., .envir = parent.frame()) {
  domo_api(verb = "DELETE", path = path, ..., .envir = .envir)
}