R/get_rstudiolog.R

In jhollist/miscPackage: Package with JWHs Miscellaneous Functions

#' Get RStudio Mirror logs
#' 
#' This function downloads the RStudio CRAN mirror logs for a date range to a 
#' specified folder.  Returns a data frame for all downloaded files
#' 
#' @param date_range
#' @param folder
#' @param missing NOT YET IMPLEMENTED
#' @export
#' @examples
#' \dontrun{
#' x<-get_rstudiolog(c(Sys.Date()-30,Sys.Date()-1),folder='rstudio_logs',missing=TRUE)
#' }
get_rstudiolog <- function(date_range = c(Sys.Date() - 2, Sys.Date() - 1), folder = ".", missing = TRUE) {
    
    # Code modified from http://cran-logs.rstudio.com/
    all_days <- unique(seq(date_range[1], date_range[2], by = "day"))
    year <- as.POSIXlt(all_days)$year + 1900
    files <- paste0(all_days, ".csv.gz")
    urls <- paste0("http://cran-logs.rstudio.com/", year, "/", files)
    
    # Checks for existence of folder, creates if doesn't exist
    if (!file.exists(folder)) {
        dir.create(folder)
    }
    
    # Only get files missing from folder
    if (missing) {
        current_files <- gsub(".gz", "", list.files(folder))
        all_files <- gsub(".gz", "", files)
        miss <- !all_files %in% current_files
        files <- files[miss]
        urls <- urls[miss]
        if (length(urls) == 0) {
            warning("All requested logs have already been downloaded.")
        }
    }
    
    # Download and unzip each log
    if (length(urls) > 0) {
        for (i in 1:length(urls)) {
            filename <- paste0(folder, "/", files[i])
            download.file(urls[i], filename)
            R.utils::gunzip(filename, overwrite = TRUE)
        }
    }
    
    # rbind_all
    xdf <- dplyr::rbind_all(lapply(list.files(folder, full.names = TRUE), function(x) read.csv(x, stringsAsFactors = FALSE)))
    return(xdf)
}