R/translate_vec.R

In paulcbauer/deeplr: Translate with DeepL

#' Translates a character vector.
#'
#' @return A character vector. If add.source.lang = TRUE a dataframe with an additional
#' column "source_lang".
#'
#' @param dataset A character vector.
#' @param source.lang Source language. Either "detect" or one of "EN", "FR", etc.
#' @param target.lang Target language. One of "EN", "FR", etc.
#' @param add.source.lang A logical. If TRUE adds the preset or detected language for each
#' translation. FALSE (default) adds nothing.
#' @param auth_key Your API key.
#' @param url Url to DeepL API.
#'
#' @examples
#' \dontrun{
#'   dat <- c("La seule facon de savoir ce qui se passe est de perturber le systeme.",
#'            "The whole problem with the world is that fools are always so certain of themselves")
#'
#' # Without language detection and without adding set/detected source language.
#'   translate_vec(dataset = dat,
#'                 source.lang = "EN",
#'                 target.lang = "DE",
#'                 auth_key = "enter you auth key here")
#'
#'   dat <- c("A dog.",
#'            "Un chien.",
#'            "Un perro.",
#'            "Un cane.",
#'            "Een hond.")
#'
#' # With language detection and with adding set/detected source language.
#'   translate_vec(dataset = dat,
#'                 source.lang = "detect",
#'                 target.lang = "DE",
#'                 add.source.lang = TRUE,
#'                 auth_key = "enter you auth key here")
#' }


translate_vec <- function(dataset = NULL,
                      source.lang = "DE",
                      target.lang = "EN",
                      add.source.lang = FALSE,
                      auth_key = NULL,
                      url = "https://api.deepl.com/v2/translate?text="
                      ) {



if(is.null(auth_key)){cat("You need an API key. See https://www.deepl.com/api-contact.html.")}else{


  if(inherits(dataset,"character")==TRUE){
    responses <- NULL
    source_lang <- NULL
    z <- 0
    for(i in dataset){
      svMisc::progress(z, max.value = length(dataset))
      z <- z+1
      i <- stringr::str_replace(gsub("\\s+", "%20", stringr::str_trim(i)), "B", "b")


      # Source language: "detect" vs. "X"
      if(source.lang=="detect"){


        response.i <- httr::GET(paste(url,
                                      i,
                                      "&target_lang=", target.lang,
                                      "&auth_key=", auth_key
                                      , sep = ""))
      }else{
        response.i <- httr::GET(paste(url,
                                      i,
                                      "&source_lang=", source.lang,
                                      "&target_lang=", target.lang,
                                      "&auth_key=", auth_key
                                      , sep = ""))
      }


      respcontent.i <- httr::content(response.i, as="text", encoding = "UTF-8")
      result.i <- jsonlite::fromJSON(respcontent.i)$translations$text
      responses <- c(responses, result.i)


    # Source language: "detect" vs. "X"
      if(source.lang == "detect"){
        source.lang.i <- jsonlite::fromJSON(respcontent.i)$translations$detected_source_language
      }else{
        source.lang.i <- jsonlite::fromJSON(respcontent.i)$translations$detected_source_language
      }
      source_lang <- c(source_lang, source.lang.i)



     }

# OUPUT

    if(add.source.lang == TRUE){
      return(data.frame(cbind(translation = responses, source_lang)))
    }else{
      return(responses)
    }




  }else{
    cat("The input is not a character vector of length > 1.")
  }


} # API KEY

} # End of function