R/realestate.R

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

#' Fetches all available area names for properties
#'
#' @return dataframe \describe{
#'   \item{area_name}{Area name}
#' }
#'
#' @examples
#'
#' fetch_property_area_name()
#'
#' @export
fetch_property_area_name <- function() {

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/property/area_name")

  # 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"))

  check_error(resp)

  tryCatch({
    return(parsed)
  },
  error=function(error_message) {
    return(data.frame())
  })
}



#' Fetches all available house types for properties
#'
#' @return dataframe \describe{
#'   \item{house_type}{House type}
#' }
#'
#' @examples
#'
#' fetch_property_house_type()
#'
#' @export
fetch_property_house_type <- function() {

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/property/house_type")

  # 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"))

  check_error(resp)

  tryCatch({
    return(parsed)
  },
  error=function(error_message) {
    return(data.frame())
  })
}


#' Fetches all available postal codes for properties
#'
#' @return dataframe \describe{
#'   \item{postal_code}{Postal code}
#' }
#'
#' @examples
#'
#' fetch_property_postal_code()
#'
#' @export
fetch_property_postal_code <- function() {

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/property/postal_code")

  # 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"))

  check_error(resp)

  tryCatch({
    return(parsed)
  },
  error=function(error_message) {
    return(data.frame())
  })
}


#' Title
#'
#' @param area_name
#' @param street_name
#'
#' @return dataframe \describe{
#'   \item{property_id}{Unique identifier for property, !!can change between days!!}
#'   \item{street_name}{Street name}
#'   \item{area_name}{Area name}
#'   \item{postal_code}{Postal code}
#'   \item{house_type}{House type}
#'   \item{square_meters}{Sqare meters m2}
#'   \item{year_built}{Year the property was build}
#'   \item{rooms}{Total number of rooms}
#'   \item{bathrooms}{Number of bathrooms}
#'   \item{bedrooms}{Number of bedrooms}
#'   \item{price}{Price in kr.}
#'   \item{date}{Date advertised}
#' }
#'
#' @examples
#' fetch_property_sale_aggregate('house_type.area_name', area_name = 'hafnarfjörður')
#'
#' @export
fetch_property_sale_aggregate <- function(by = c('area_name', 'house_type', 'postal_code', 'house_type.area_name', 'house_type.postal_code',
                                                  'house_type.area_name.postal_code', 'house_type.area_name.year_built'),
                                          area_name = '',
                                          house_type = c('fjölbýlishús', 'einbýlishús', 'par/raðhús', 'hæð'),
                                          frequency = c('day', 'week', 'month', NULL),
                                          from = '2017-10-01', to = NULL) {

  # Check input arguments
  collection <- checkmate::makeAssertCollection()
  checkmate::assertString(by, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::assertString(area_name, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::reportAssertions(collection)

  if (!is.null(house_type)) house_type <- match.arg(house_type)
  frequency <- match.arg(frequency)
  by <- match.arg(by)


  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    paste0("/property/sale/", gsub('.', '/', by, fixed = T)))

  # Make API call and parse
  resp <- httr::GET(
    url,
    httr::add_headers("Authorization" = getOption("authentication_key", default = "")),
    httr::accept_json(),
    query = list(house_type = tolower(house_type),
                 area_name = tolower(area_name),
                 frequency = tolower(frequency),
                 from = from,
                 to = to))

  check_error(resp)

  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 <- unnest(parsed)
    parsed$date <- as.Date(parsed$date)
    return(parsed)
  },
  error=function(error_message) {
    return(setNames(data.frame(matrix(ncol = 12, nrow = 0)),
                    c("house_type", "area_name", "year_built", "postal_code",
                      "date", "price", "stddev_price",
                      "sqm_price", "stddev_sqm_price",
                      "sqm", "stddev_sqm", "total")))
  })
}




#' Title
#'
#' @param area_name
#' @param street_name
#'
#' @return dataframe \describe{
#'   \item{property_id}{Unique identifier for property, !!can change between days!!}
#'   \item{street_name}{Street name}
#'   \item{area_name}{Area name}
#'   \item{postal_code}{Postal code}
#'   \item{house_type}{House type}
#'   \item{square_meters}{Sqare meters m2}
#'   \item{year_built}{Year the property was build}
#'   \item{rooms}{Total number of rooms}
#'   \item{bathrooms}{Number of bathrooms}
#'   \item{bedrooms}{Number of bedrooms}
#'   \item{price}{Price in kr.}
#'   \item{date}{Date advertised}
#' }
#'
#' @examples
#' fetch_property_sale(area_name = 'hafnarfjörður')
#'
#' @export
fetch_property_sale <- function(area_name = '', street_name = '') {

  # Check input arguments
  collection <- checkmate::makeAssertCollection()
  checkmate::assertString(area_name, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::assertString(street_name, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::reportAssertions(collection)

  if (area_name == '' && street_name == '') {
    stop(
      sprintf(
        "Either area_name or street_name must be filled."
      ),
      call. = FALSE
    )
  }

  if (street_name != '' && nchar(street_name) < 3) {
    stop(
      sprintf(
        "street_name must contain a string longer than 2."
      ),
      call. = FALSE
    )
  }

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/property/sale/")

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

  check_error(resp)

  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 <- unnest(parsed)
    parsed$date <- as.Date(parsed$date)
    return(parsed)
  },
  error=function(error_message) {
    return(setNames(data.frame(matrix(ncol = 11, nrow = 0)), c("property_id", "street_name", "area_name", "postal_code", "house_type", "square_meters", "rooms", "bedrooms", "bathrooms", "price", "date")))
  })
}




#' Title
#'
#' @param area_name
#' @param street_name
#'
#' @return dataframe \describe{
#'   \item{property_id}{Unique identifier for property, !!can change between days!!}
#'   \item{street_name}{Street name}
#'   \item{area_name}{Area name}
#'   \item{postal_code}{Postal code}
#'   \item{house_type}{House type}
#'   \item{square_meters}{Sqare meters m2}
#'   \item{year_built}{Year the property was build}
#'   \item{rooms}{Total number of rooms}
#'   \item{bathrooms}{Number of bathrooms}
#'   \item{bedrooms}{Number of bedrooms}
#'   \item{price}{Rent price in kr.}
#'   \item{date}{Date advertised}
#' }
#'
#' @examples
#' fetch_property_rent(area_name = 'hafnarfjörður')
#'
#' @export
fetch_property_rent <- function(area_name = '', street_name = '') {

  # Check input arguments
  collection <- checkmate::makeAssertCollection()
  checkmate::assertString(area_name, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::assertString(street_name, na.ok = FALSE, min.chars = 0, add = collection)
  checkmate::reportAssertions(collection)

  if (area_name == '' && street_name == '') {
    stop(
      sprintf(
        "Either area_name or street_name must be filled."
      ),
      call. = FALSE
    )
  }

  if (street_name != '' && nchar(street_name) < 3) {
    stop(
      sprintf(
        "street_name must contain a string longer than 2."
      ),
      call. = FALSE
    )
  }

  # Create url
  url <- paste0(
    getOption("base_path", default = "https://api.datahub.is"),
    "/property/rent/")

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

  check_error(resp)

  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 <- unnest(parsed)
    parsed$date <- as.Date(parsed$date)
    return(parsed)
  },
  error=function(error_message) {
    return(setNames(data.frame(matrix(ncol = 11, nrow = 0)), c("property_id", "street_name", "area_name", "postal_code", "house_type", "square_meters", "rooms", "bedrooms", "bathrooms", "price", "date")))
  })
}