backup-db.rb

#!/usr/lib/env ruby
 
# Acquires a shared lock on a SQLite database file and copies it to a backup
#
# usage:  backup-db.rb DBFILE.db
# output: Creates backup copy of database to same directory with "dbbackup #{datetime}" prepended
# author: Paul Malenke (@paulmalenke), Forked from William Benton ([email protected]) at https://gist.github.com/willb/3518892
#
# Public domain.
 
require 'sqlite3'
require 'fileutils'
require 'time'

def set_backup_filename(db_file)
  path = File.dirname(db_file) << "/"
  file = File.basename(db_file)
  file.prepend(Time.now.strftime("dbbackup %Y-%m-%d %I.%M.%S%p "))
  path << file
end
 
def backup_db(db_file, backup_file)
  begin
    db = SQLite3::Database.new(db_file)
 
    db.transaction(:immediate) do |ignored|
      # starting a transaction with ":immediate" means we get a shared lock
      # and thus any db writes (unlikely!) complete before we copy the file
      FileUtils.cp(db_file, backup_file, :preserve=>true)
    end
  ensure
    db.close
  end
end

backup_db(ARGV[0], set_backup_filename(ARGV[0]))