R/geo_json_parse.R

In RobertMyles/tidygeoRSS: Tidy GeoRSS

# Parses GeoJSON feeds.
# Feed is transformed to character to be read in by sf.
# Metadata is parsed with jsonlite, both are then combined.
# No tidying is done on 'sf' results, these are commonly extended
# and so can't be known beforehand.
geo_json_parse <- function(response, feed, list, clean_tags, parse_dates) {
  j_parsed <- parse_json(response)
  geocheck <- j_parsed$type == "FeatureCollection"

  if (isTRUE(geocheck)) {
    j_text <- as.character(response)
    sf_result <- read_sf(j_text)
    m <- j_parsed$metadata
    title <- m$title
    if (is.null(title)) title <- feed
    url <- m$url
    gen <- m$generated
    meta <- tibble(
      feed_title = ifelse(!is.null(title), title, def),
      feed_url = ifelse(!is.null(url), url, def),
      time_generated = ifelse(!is.null(gen), gen, def)
    )

    meta <- clean_up(meta, "json", clean_tags, parse_dates)
    entries <- clean_up(sf_result, "json", clean_tags, parse_dates) %>% 
      st_as_sf()

    if (isTRUE(list)) {
      result <- list(meta = meta, entries = entries)
    } else {
      entries$feed_title <- title
      result <- suppressMessages(full_join(meta, entries))
    }
    return(result)
  } else {
    stop(msg)
  }
}