R/fct_helpers.R

In rsqliteadmin: A GUI to Manage SQLite Databases

# Note: For SQLite, A keyword in single quotes ('') is a string literal
#               and A keyword in double-quotes ("") is an identifier.

## Functions for module create_databases

# Returns the list of databases in folder "directory"
db_list <- function(directory = NULL) {
  if (is.null(directory))
    return(NULL)
  return(list.files(path = directory, pattern = ".db$"))
}

# Creates a new database
create_db <- function(name = NULL, directory = NULL) {
  db_name <- paste0(directory, name, ".db")
  conn <- RSQLite::dbConnect(RSQLite::SQLite(), db_name)
  RSQLite::dbDisconnect(conn)
}

## Functions for module dashboard_structure

# Reference Here: https://stackoverflow.com/a/37595263
convertMenuItem <- function(mi, tabName) {
  mi$children[[1]]$attribs['data-toggle'] = "tab"
  mi$children[[1]]$attribs['data-value'] = tabName
  if (length(mi$attribs$class) > 0 &&
      mi$attribs$class == "treeview") {
    mi$attribs$class = NULL
  }
  mi
}

# Update the database list without tables in the sidebar.
update_sidebar_db <- function(db_list) {
  db_menu <- list()
  for (i in seq_len(length(db_list))) {
    db_menu[[i]] <-
      convertMenuItem(
        shinydashboard::menuItem(
          text = db_list[i],
          tabName = paste0("db_", i),
          icon = icon("database", lib = "font-awesome")
        ),
        paste0("db_", i)
      )
  }
  return(db_menu)
}

# Update the database list with tables in the sidebar.
update_sidebar_table <-
  function(input_sidebar_menu, active_db, db_list) {
    selected_db_index <- strtoi(substr(
      input_sidebar_menu,
      start = 4,
      stop = nchar(input_sidebar_menu)
    ))
    selected_db <- db_list[selected_db_index]
    
    table_list <- RSQLite::dbListTables(active_db)
    
    db_menu <- list()
    for (i in seq_len(length(db_list))) {
      if (db_list[i] == selected_db &&
          !identical(table_list, character(0)))
      {
        db_menu[[i]] <-
          convertMenuItem(
            shinydashboard::menuItem(
              text = db_list[i],
              tabName = paste0("db_", i),
              icon = icon("database", lib = "font-awesome"),
              startExpanded = TRUE,
              lapply(1:length(table_list), function(i) {
                shinydashboard::menuSubItem(text = table_list[i],
                                            tabName = paste0("table_", i),
                                            icon = icon("table", lib = "font-awesome"))
              })
            ),
            paste0("db_", i)
          )
      }
      else{
        db_menu[[i]] <-
          convertMenuItem(
            shinydashboard::menuItem(
              text = db_list[i],
              tabName = paste0("db_", i),
              icon = icon("database", lib = "font-awesome")
            ),
            paste0("db_", i)
          )
      }
    }
    
    return(db_menu)
  }