R/validate_gids.R

In keberwein/gameday_dev: Tools to Gather Data from Major League Baseball Advanced Media (MLBAM)

#' Internal function to validate gids produced by try_gids.
#' @param gidslist a list of gids.
#' @param league The league to gather gids for. The default is \code{"mlb"}. Other options include \code{"aaa"} and \code{"aa"}.
#' @param ... additional arguments
#' @import foreach
#' @importFrom purrr map map_chr
#' @importFrom stringr str_sub str_length
#' @importFrom data.table data.table setnames rbindlist
#' @import foreach
#' @keywords internal
#' @export

validate_gids <- function(gidslist=NULL, league="mlb", ...) {
    # Rename league because it conflicts with some downloaded xml values.
    lg <- league
    # Create an emply list to hold the results of the loop.
    gidslist_dt=i=str_length=NULL
    root <- "http://gd2.mlb.com/components/game/"
    
    # Get start and end dates from gids.
    gidslist_dt <- data.table::data.table(gidslist) %>% 
        data.table::setnames(old = "gidslist", new = "link")
    
    # Use miniscorboard to validate urls. Set class to mini so we can use the payload function.
    minilist <- gidslist_dt$link %>% purrr::map_chr(~ paste0(., "/miniscoreboard.xml"))
    
    # Do a tryCatch along the dates. If the url exists, get the payload from miniscorboard.
    out <- foreach::foreach(i = seq_along(minilist), .inorder=FALSE) %dopar% {
        file <- tryCatch(xml2::read_xml(minilist[[i]]), error=function(e) NULL)
        if(!is.null(file)){
            mini_nodes <- xml2::xml_find_all(file, "./game")
            mini <- purrr::map_dfr(mini_nodes, function(x) {
                out <- data.frame(t(xml2::xml_attrs(x)), stringsAsFactors=FALSE)
                out
            })
        }
    }
    
    #games <- dplyr::bind_rows(out)
    games <- data.table::rbindlist(out)
    
    gidz <- games %>%
        .[, url := paste0(root, lg, "/", "year_", str_sub(gameday_link, 1, 4), "/", "month_",
                          str_sub(gameday_link, 6, 7), "/", "day_", str_sub(gameday_link, 9, 10), 
                          "/gid_", gameday_link)]
    gidz <- gidz$url
    
    #dplyr::mutate(url = paste0(root, lg, "/", "year_", str_sub(gameday_link, 1, 4), "/", "month_",
    #                                        str_sub(gameday_link, 6, 7), "/", "day_", str_sub(gameday_link, 9, 10), 
    #                                        "/gid_", gameday_link)) %>% 
    #select(url)
    
    # Needs to be a list so payload will read it correct
    gidz <- gidz$url %>% as.list
    
    return(gidz)
}