R/install_tika.R

In ropensci/rtika: R Interface to 'Apache Tika'

#' Install or Update the Apache Tika \code{jar}
#'
#' This downloads and installs the Tika App \code{jar} (~60 MB) into a user directory,
#' and verifies the integrity of the file using a checksum.
#' The default settings should work fine.
#'
#' @param version The declared Tika version
#' @param digest The sha512 checksum. Set to an empty string \code{""} to skip the check.
#' @param mirrors A vector of Apache mirror sites. One is picked randomly.
#' @param retries The number of times to try the download.
#' @param url Optional url to a particular location of the tika app. Setting this to any character string overrides downloading from random mirrors.
#'
#' @return Logical if the installation was successful.
#' @examples
#' \donttest{
#' install_tika()
#' }
#' @section Details:
#' The default settings of \code{install_tika()} should typically be left as they are.
#'
#' This function will download the version of the Tika \code{jar} tested to work
#' with this package, and can verify file integrity using a checksum.
#'
#' It will normally download from a random Apache mirror.
#' If the mirror fails,
#' it tries the archive at \code{http://archive.apache.org/dist/tika/}.
#' You can also enter a value for \code{url} directly to override this.
#'
#' It will download into a directory determined
#' by \code{tools::R_user_dir("rtika", which = "data")},
#' specific to the operating system.
#'
#' If \code{tika()} is stopping with an error compalining about the \code{jar},
#' try running \code{install_tika()} again.
#'
#' @section Uninstalling:
#' If you are uninstalling the entire \code{rtika} package
#' and want to remove the Tika App \code{jar} also,
#' run:
#'
#'  \code{unlink(tools::R_user_dir("rtika", which = "data"), recursive = TRUE)}
#'
#' Alternately, navigate to the install folder and delete it manually.
#' It is the file path returned by 
#' \code{tools::R_user_dir("rtika", which = "data")}.
#' The path is OS specific.
#' 
#' @section Distribution:
#' Tika is distributed under the Apache License Version 2.0,
#' which generally permits distribution of the code "Object" without the "Source".
#' The master copy of the Apache Tika source code is held in GIT. 
#' You can fetch (clone) the large source from GitHub ( https://github.com/apache/tika ).
#'
#' @export

install_tika <- function(version = "2.7.0",
                         digest = paste0("7fefbe5570a95900d39193134e8277aec99e5450a8",
                                         "cecbb5787b3d6651ebf735e460ccccddb49bdc2990",
                                         "8a9058fc36e4689aed6da6d63a1cf70ca09ccf26bcca"),
                         mirrors = c(
                           "https://ftp.wayne.edu/apache/tika/",
                           "http://mirrors.ocf.berkeley.edu/apache/tika/",
                           "http://apache.cs.utah.edu/tika/",
                           "http://mirror.cc.columbia.edu/pub/software/apache/tika/"
                         ),
                         retries = 2,
                         url = character()) {
   
     # Get user directory  -------------------
     user_data_dir <-
    normalizePath(
      R_user_dir("rtika", which = "data"),
      mustWork = FALSE
    ) # tools::R_user_dir works on R > 4


  if (!dir.exists(user_data_dir)) {
    dir.create(
      user_data_dir,
      recursive = TRUE,
      showWarnings = FALSE
    )
    if (!file.exists(user_data_dir)) {
      stop("Could not create use directory to download file. Stopping.")
    }
  }

  if (length(url) == 0 || nchar(url) == 0) {
    random_mirror <- sample(mirrors, 1)

    url <- paste0(
      random_mirror,
      paste0( version, "/", "tika-app-", version, ".jar")
    )
  }

  message(
    "Downloading the Tika App .jar version ", version, ' into "',
    user_data_dir,
    '". The file is approximately 60 MB - this may take a while.'
  )

  download <- tika_fetch(
    url,
    download_dir = user_data_dir,
    retries = retries
  )

  if (is.na(download)) {
     message('Could not download the Tika App .jar from mirror "', url, '".
Trying the Apache archive.')

    url <- paste0(
      "http://archive.apache.org/dist/tika/",
      paste0( version, "/", "tika-app-", version, ".jar")
    )

    download <- tika_fetch(
      url,
      download_dir = user_data_dir,
      retries = retries
    )

    if (is.na(download)) {
      stop('Could not download the Tika App .jar from the archive "', url, '". 
Stopping. Try running install_tika() again, setting url to a particular path.')
    }
  }

  path <- file.path(user_data_dir, "tika-app.jar")

  renamed <- file.rename(download, path)

  if (!renamed) {
    stop("Could not rename the temporary download file on this system.
Removing the temporary file and stopping the installation.")
    file.remove(download)
  }

  exists <- tika_jar()

  if (!is.na(exists)) {
    message("The download is successful.")
  } else {
    stop('Stopping. The "tika_jar()" funtion could not find the Tika App .jar')
  }

  if (nchar(digest) > 0) {
    file_integrity <- tika_check(digest)

    if (!file_integrity) {
      stop("The Tika App .jar integrity is bad! It failed the checksum test.
    Removing the file and stopping installation.")
      file.remove(exists)
    } else {
      message("The file integrity is good.")
    }
  }

  writeLines(text = as.character(version), file.path(user_data_dir, "tika-app-version.txt"))

  message("The installation is successful.")
  return(invisible(TRUE))
}