R/stock.R

In palmargisla/datahub-r: Gets data from Datahub.is

#' Fetches stock historical data from DataHub
#'
#' @param code the code of the interest series
#' @param source_code the source code of the interest series
#' @param query optional, availible list(from = yyyy-mm-dd, to = yyyy-mm-dd)
#'
#' @return dataframe \describe{
#'   \item{code}{interest series code}
#'   \item{source_code}{source code}
#'   \item{date}{series date}
#'   \item{closing_price}{Closing price}
#'   \item{opening_price}{Opening price}
#'   \item{bid_price}{Bid price}
#'   \item{ask_price}{Ask price}
#'   \item{high_price}{High price of the day}
#'   \item{low_price}{Low price of the day}
#'   \item{volume}{Volume traded}
#' }
#'
#' @examples
#' fetch_interest('ICEAIR', 'NASDAQ')
#'
#' @export
fetch_stock <- function(code, source_code, query = list()) {

  # Check input arguments
  collection <- checkmate::makeAssertCollection()
  checkmate::assertString(code, na.ok = FALSE, min.chars = 1, add = collection)
  checkmate::assertString(source_code, na.ok = FALSE, min.chars = 1, add = collection)
  checkmate::assertList(query, add = collection)
  checkmate::reportAssertions(collection)

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/stock/",
    toupper(code),
    "/source/",
    toupper(source_code),
    "/quote")

  # Make API call and parse
  resp <- httr::GET(
    url,
    httr::add_headers("Authorization" = getOption("authentication_key", default = "")),
    httr::accept_json(),
    query = query)

  parsed <- jsonlite::fromJSON(httr::content(resp, "text", encoding = "UTF-8"))

  #* Stop if errors
  if (httr::http_error(resp)) {
    stop(
      sprintf(
        "DataHub API request failed [%s]\n%s\n<%s>",
        httr::status_code(resp),
        parsed$message,
        parsed$errors
      ),
      call. = FALSE
    )
  }

  tryCatch({
    parsed$date = as.Date(parsed$date)
    return(parsed)
  },
  error=function(error_message) {
    return(setNames(data.frame(matrix(ncol = 10, nrow = 0)), c("code", "source_code", "date",
                                                               "closing_price", "opening_price",
                                                               "bid_price", "ask_price",
                                                               "high_price", "low_price", "volume")))
  })
}

#' Fetches all available stocks
#'
#' @return dataframe \describe{
#'   \item{code}{interest code}
#'   \item{name}{interest name}
#'   \item{source_code}{source code}
#'   \item{source_name}{source name, use this for caption}
#'   \item{isin}{isin number}
#'   \item{sector}{sector}
#'   \item{description}{description of this series}
#'   \item{last_update}{date this series was last updated}
#'   \item{usage}{code example on how to call for the dataseries}
#' }
#'
#' @examples
#' fetch_stock_info()
#'
#' @export
fetch_stock_info <- function() {
  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/stock")

  # Make API call and parse
  resp <- httr::GET(
    url,
    httr::add_headers("Authorization" = getOption("authentication_key", default = "")),
    httr::accept_json())

  parsed <- jsonlite::fromJSON(httr::content(resp, "text", encoding = "UTF-8"))

  #* Stop if errors
  if (httr::http_error(resp)) {
    stop(
      sprintf(
        "DataHub API request failed [%s]\n%s\n<%s>",
        httr::status_code(resp),
        parsed$message,
        parsed$errors
      ),
      call. = FALSE
    )
  }

  parsed <- parsed %>%
    select(code, name, source_code, source_name, isin, sector, description, last_update) %>%
    mutate(usage = paste0("fetch_stock('", code, "','", source_code, "')"))

  parsed
}