amahi/platform

# Amahi Home Server
# Copyright (C) 2007-2013 Amahi
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License v3
# (29 June 2007), as published in the COPYING file.
#
# 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
# file COPYING for more details.
#
# You should have received a copy of the GNU General Public
# License along with this program; if not, write to the Amahi
# team at http://www.amahi.org/ under "Contact Us."

class Db < ApplicationRecord

    DB_BACKUPS_DIR = "/var/hda/dbs"

    after_create :after_create_hook
    after_destroy :after_destroy_hook

    # stubs for name, password and hostname, in case they need changed later

    def username
        name
    end

    def password
        name
    end

    def hostname
        "localhost"
    end

private

    def after_create_hook
        return unless Rails.env.production?
        c = self.class.connection
        password = name
        user = name
        host = 'localhost'
        c.execute "DROP DATABASE IF EXISTS `#{name}`;" rescue nil
        c.execute "CREATE DATABASE IF NOT EXISTS `#{name}` DEFAULT CHARACTER SET utf8;"
        # FIXME - why do we have to drop the user first in some cases?!?!!??
        c.execute("DROP USER '#{user}'@'#{host}';") rescue nil
        c.execute "CREATE USER '#{user}'@'#{host}' IDENTIFIED BY '#{password}';"
        c.execute "GRANT ALL PRIVILEGES ON `#{name}`.* TO '#{user}'@'#{host}';"
    end

    def after_destroy_hook
        return unless Rails.env.production?
        user = name
        filename = Time.now.strftime("#{DB_BACKUPS_DIR}/%y%m%d-%H%M%S-#{name}.sql.bz2")
        system("mysqldump --add-drop-table -u#{user} -p#{user} #{name} | bzip2 > #{filename}")
        Dir.chdir(DB_BACKUPS_DIR) do
            system("ln -sf #{filename} latest-#{name}.bz2")
        end
        c = self.class.connection
        host = 'localhost'
        c.execute "DROP USER '#{user}'@'#{host}';"
        c.execute "DROP DATABASE IF EXISTS `#{name}`;"
    end
end