Returns a data frame of selected information on all packages on CRAN

getCRANPackages.R

#' @description Returns a list of all packages on CRAN
#' @param columns_list A character vector of field names to return from package DESCRIPTION files
#' @return A data frame containing all packages on CRAN
#' @details Function modified from StackOverflow answer at \url{https://stackoverflow.com/a/11561793}.
#' @importFrom magrittr %>%
#' @importFrom tibble as.tibble
#' @importFrom dplyr select_
getCRANPackages <- function(columns_list = c("Package", "Title", "Version", "Date", "Published", "URL")) {
  contrib.url(getOption("repos")["CRAN"], "source") 
  description <- sprintf("%s/web/packages/packages.rds", 
                         getOption("repos")["CRAN"])
  con <- if(substring(description, 1L, 7L) == "file://") {
    file(description, "rb")
  } else {
    url(description, "rb")
  }
  on.exit(close(con))
  db <- readRDS(gzcon(con))
  rownames(db) <- NULL
  
  db <- db %>% as.tibble() %>% 
    select_(.dots = columns_list)
  return(db)
}