Snippets for remote nginx reload

lualib.conf

# located at /etc/nginx/conf.d/lualib.conf
lua_package_path "/etc/nginx/lualib/?.lua;;";

reload.lua

-- located at /etc/nginx/lualib/reload.lua
local _M = {}

local ffi = require "ffi"
ffi.cdef[[
int32_t getppid();
int kill(int32_t pid, int signal);
]]

SIGHUP = 1

local function getppid()
    return ffi.C.getppid()
end

local function kill(pid, sig)
    return ffi.C.kill(pid, sig)
end

local function reload()
    return kill(getppid(), SIGHUP)
end

_M.reload = reload
return _M

reload_snippet.conf

       location /reload {
            content_by_lua_block {
                local reload = require "reload"
                ngx.say(reload.reload())
            }

setcap.sh

#!/bin/sh
setcap cap_net_bind_service+ep `which nginx`