R/dbR6Parent_initialize.R

In leandroroser/dbR6: Databases Manipulation with the dbR6 Class

#' dbR6Parent_initialize__
#'@keywords internal

dbR6Parent_initialize <- function(...)  {

  # if file is xxx.sqlite, remove the .sqlite part
  if(length(grep(".sqlite$", filename, ignore.case = TRUE)) != 0) {
    filename <- gsub(".sqlite$", "", filename, ignore.case = TRUE)
  }

  # return_value = TRUE if an existing database is read from disk.
  # This is an indicator to detect if exists previous metadata
  return_value <- FALSE

  # automatically add file type
  if(filename != ":memory:") {
    if(length(grep("/", filename)) == 0) {
    parent_dir <- getwd()
    data_name <- file.path(getwd(), paste0(filename, ".sqlite"))
    metadata_name <-  file.path(getwd(), paste0(filename, ".json.gz"))

    } else {

      parent_dir <- normalizePath(gsub("(.*)(/.*?)$", "\\1", filename),
                                  mustWork = TRUE)
      data_name <- paste0(filename, ".sqlite")
      metadata_name <-  paste0(filename, ".json.gz")
    }

    dir_content <- normalizePath(dir(path = parent_dir,
      full.names = TRUE), mustWork = TRUE)

    if(overwrite) {
      if(length(grep(data_name, dir_content)) > 0) {
        suppressMessages(file.remove(data_name))
        message("Overwriting database...")
      } else {
        message("Creating new database...\n")
      }
      return_value <- FALSE
      file.create(data_name)
      file.create(metadata_name)
    } else {
      if(length(grep(data_name, dir_content)) > 0) {
        message(paste0("Connecting with existing database: ", data_name, "\n"))
        if(!file.exists(metadata_name)) {
          warning("No metadata found for sqlite object. Creating new metadata...\n")
          file.create(metadata_name)
        }
        return_value <- TRUE
      } else {
        message("Creating new database...\n")
        file.create(data_name)
        file.create(metadata_name)
        return_value <- FALSE
      }
    }

  } else {

    if(overwrite) {
      stop("A file must be selected when overwrite is TRUE\n")
    }

    data_name <- ":memory:"
    metadata_name <- ":memory:"
  }

  # if(data_name != ":memory:") {
  #   data_name <- normalizePath(data_name)
  #   metadata_name <- normalizePath(metadata_name)
  # }



  private$where <- new.env(parent = emptyenv(), hash = FALSE)
  private$where$data <- RSQLite::dbConnect(RSQLite::SQLite(), data_name)
  private$path <- list(data = data_name, metadata = metadata_name)

  if(filename == ":memory:") {
    message("Database created in memory\n")
  } else {
    message(paste0("Database located in: ", data_name))
  }

  return_value
}