R/StoreFileExtPipe.R

In bdpar: Big Data Preprocessing Architecture

#
# Bdpar provide a tool to easily build customized data flows to pre-process
# large volumes of information from different sources. To this end, bdpar allows
# to (i) easily use and create new functionalities and (ii) develop new data
# source extractors according to the user needs. Additionally, the package
# provides by default a predefined data flow to extract and preprocess the most
# relevant information (tokens, dates, ... ) from some textual sources (SMS,
# email, tweets, YouTube comments).
#
# Copyright (C) 2020-2022 Sing Group (University of Vigo)
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# this program. If not, see <https://www.gnu.org/licenses/gpl-3.0.html>

#' @title Class to get the file's extension field of an Instance
#'
#' @description Gets the extension of a file. Creates the \strong{extension}
#' property which indicates extension of the file.
#'
#' @section Note:
#' \code{\link{StoreFileExtPipe}} will automatically invalidate the
#' \code{\link{Instance}} if it is not able to find the
#' extension from the path field.
#'
#' @section Inherit:
#' This class inherits from \code{\link{GenericPipe}} and implements the
#' \code{pipe} abstract function.
#'
#' @seealso \code{\link{AbbreviationPipe}}, \code{\link{ContractionPipe}},
#'          \code{\link{File2Pipe}}, \code{\link{FindEmojiPipe}},
#'          \code{\link{FindEmoticonPipe}}, \code{\link{FindHashtagPipe}},
#'          \code{\link{FindUrlPipe}}, \code{\link{FindUserNamePipe}},
#'          \code{\link{GuessDatePipe}}, \code{\link{GuessLanguagePipe}},
#'          \code{\link{Instance}}, \code{\link{InterjectionPipe}},
#'          \code{\link{MeasureLengthPipe}}, \code{\link{GenericPipe}},
#'          \code{\link{ResourceHandler}}, \code{\link{SlangPipe}},
#'          \code{\link{StopWordPipe}}, \code{\link{TargetAssigningPipe}},
#'          \code{\link{TeeCSVPipe}}, \code{\link{ToLowerCasePipe}}
#'
#' @keywords NULL
#'
#' @import R6
#' @export StoreFileExtPipe

StoreFileExtPipe <- R6Class(

  "StoreFileExtPipe",

  inherit = GenericPipe,

  public = list(
    #'
    #' @description Creates a \code{\link{StoreFileExtPipe}} object.
    #'
    #' @param propertyName A \code{\link{character}} value. Name of the property
    #' associated with the \code{\link{GenericPipe}}.
    #' @param alwaysBeforeDeps A \code{\link{list}} value. The dependencies
    #' alwaysBefore (\code{\link{GenericPipe}s} that must be executed before
    #' this one).
    #' @param notAfterDeps A \code{\link{list}} value. The dependencies
    #' notAfter (\code{\link{GenericPipe}s} that cannot be executed after
    #' this one).
    #'
    initialize = function(propertyName = "extension",
                          alwaysBeforeDeps = list(),
                          notAfterDeps = list()) {

      if (!"character" %in% class(propertyName)) {
        bdpar.log(message = paste0("Checking the type of the 'propertyName' variable: ",
                                   class(propertyName)),
                  level = "FATAL",
                  className = class(self)[1],
                  methodName = "initialize")
      }

      if (!"list" %in% class(alwaysBeforeDeps)) {
        bdpar.log(message = paste0("Checking the type of the 'alwaysBeforeDeps' variable: ",
                                   class(alwaysBeforeDeps)),
                  level = "FATAL",
                  className = class(self)[1],
                  methodName = "initialize")
      }

      if (!"list" %in% class(notAfterDeps)) {
        bdpar.log(message = paste0("Checking the type of the 'notAfterDeps' variable: ",
                                   class(notAfterDeps)),
                  level = "FATAL",
                  className = class(self)[1],
                  methodName = "initialize")
      }

      super$initialize(propertyName, alwaysBeforeDeps, notAfterDeps)
    },
    #'
    #' @description Preprocesses the \code{\link{Instance}} to obtain the
    #' extension of \code{\link{Instance}}.
    #'
    #' @param instance A \code{\link{Instance}} value. The \code{\link{Instance}}
    #' to preprocess.
    #'
    #' @return The \code{\link{Instance}} with the modifications that have
    #' occurred in the pipe.
    #'
    pipe = function(instance) {

      if (!"Instance" %in% class(instance)) {
        bdpar.log(message = paste0("Checking the type of the 'instance' variable: ",
                                   class(instance)),
                  level = "FATAL",
                  className = class(self)[1],
                  methodName = "pipe")
      }

      instance$addProperties(self$obtainExtension(instance$getPath()),
                             super$getPropertyName())

      if (instance$getSpecificProperty("extension") %in% "") {

        message <- paste0("The file: ", instance$getPath(), " has not an extension")

        instance$addProperties(message, "reasonToInvalidate")

        bdpar.log(message = message,
                  level = "WARN",
                  className = class(self)[1],
                  methodName = "pipe")

        instance$invalidate()

        return(instance)

      }

      instance
    },
    #'
    #' @description Gets of extension of the path.
    #'
    #' @param path A \code{\link{character}} value. The path of the file to get
    #' the extension.
    #'
    #' @return Extension of the path.
    #'
    #' @import tools
    #'
    obtainExtension = function(path) {

      if (!"character" %in% class(path)) {
        bdpar.log(message = paste0("Checking the type of the 'path' variable: ",
                                   class(path)),
                  level = "FATAL",
                  className = class(self)[1],
                  methodName = "obtainExtension")
      }

      file_ext(path)
    }
  )
)