aredn/files/etc/cron.hourly/check-services

#!/usr/bin/lua
--[[

	Part of AREDN -- Used for creating Amateur Radio Emergency Data Networks
	Copyright (C) 2022-2023 Tim Wilkinson
	See Contributors file for additional contributors

	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 version 3 of the License.

	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 <http://www.gnu.org/licenses/>.

	Additional Terms:

	Additional use restrictions exist on the AREDN(TM) trademark and logo.
		See AREDNLicense.txt for more info.

	Attributions to the AREDN Project must be retained in the source code.
	If importing this code into a new or existing project attribution
	to the AREDN project must be added to the source code.

	You must not misrepresent the origin of the material contained within.

	Modified versions must be modified to attribute to the original source
	and be marked in reasonable ways as differentiate it from the original
	version

--]]

require("uci")
require("aredn.services")

local cursor = uci.cursor()

-- Current nameserver state
local ns = cursor:get_all("olsrd", "nameservice")
if not ns then
    print("Missing nameservice")
    return
end
local cnames = {}
for _, name in ipairs(ns.name)
do
    cnames[name] = true
end
local chosts = {}
for k, v in pairs(ns)
do
    if k:match("^%d+_%d+_%d+_%d+$") then
        chosts[k:gsub("_", ".")] = v
    end
end
local cservices = {}
for _, service in ipairs(ns.service or {})
do
    cservices[service] = true
end

-- Work out the differences between the validated state and the current state
local names, hosts, services = aredn.services.get(true)
local nnames = false
for _, name in ipairs(names)
do
    if cnames[name] then
        cnames[name] = nil
    else
        nnames = true
    end
end
local nhosts = {}
for _, host in ipairs(hosts)
do
    if chosts[host.ip] then
        chosts[host.ip] = nil
    else
        nhosts[host.ip] = host.host
    end
end
local nservices = false
for _, service in ipairs(services)
do
    if cservices[service] then
        cservices[service] = nil
    else
        nservices = true
    end
end

function not_empty(h)
    for _, _ in pairs(h)
    do
        return true
    end
    return false
end

local change = false

-- Apply the changes
if nnames or not_empty(cnames) then
    cursor:set("olsrd", "nameserver", "name", names)
    change = true
end
if not_empty(chosts) or not_empty(nhosts) then
    for k, _ in pairs(chosts)
    do
        cursor:delete("olsrd", "nameserver", k)
    end
    for k, v in pairs(nhosts)
    do
        cursor:set("olsrd", "nameserver", k, v)
    end
    change = true
end
if nservices or not_empty(cservices) then
    cursor:set("olsrd", "nameserver", "service", services)
    change = true
end

-- If services have changed we need to restart olsrd
if change then
    cursor:commit("olsrd")
    print("Change")
    os.execute("/etc/init.d/olsrd restart > /dev/null 2>&1")
else
    print("Unchange")
end