R/01_install_OCR_packages.R

In arete: Automated REtrieval from TExt

#' Update OCR dependencies
#' @description Install python dependencies needed to run the optional OCR utilities in arete.
#' @param envname character. Name or path to the Python virtual environment being used for arete.
#' @param verbose logical. Determines if output should be printed.
#' @param ... Other parameters to pass to the installation function as per the documentation of \code{\link[reticulate]{py_install}}
#' @return NULL. If any packages failed to install, a character listing which.
#' @seealso \code{\link{arete_setup}}
#' @examples 
#' \dontrun{
#' install_OCR_packages("./path/to/venv")
#' }
#' @export
install_OCR_packages <- function(envname = "arete", verbose = TRUE, ...){
  packages <- c(
    "nougat-ocr", "tesseract"
  )
  if (verbose){
    if (Sys.info()["sysname"] == "Linux") {
      message("Please check for additional dependencies @: https://github.com/UB-Mannheim/tesseract/wiki.")
    } else if (Sys.info()["sysname"] == "Windows"){
      message("The installation of a standalone tesseract is currently only supported in Linux.")
    } else {
      message("The installation of a standalone tesseract is currently only supported in Linux.")
    }
  }

  failed = c()
  for (i in packages) {
    
    try_install = tryCatch({
      if (verbose){
        reticulate::py_install(i, envname = envname, method = "auto", ...)
      } else {
        suppressMessages(reticulate::py_install(i, envname = envname, method = "auto", ...))
      }
      try_install = FALSE
    }, error = function(e){
      try_install = TRUE
    })
    
    if (try_install){
      failed = c(failed, i)
    }
  }
  
  if (length(failed) != 0){
    if (verbose){
      message("Error: Python package installation failed for: ", paste(failed, collapse = ", "))
    }
    return(failed)
  } else {
    return(NULL)
  }
}