From e5d00cfa23d443fca526eedb495fecdc872b32c2 Mon Sep 17 00:00:00 2001
From: Lukas Werner <lukas.m.werner@outlook.com>
Date: Wed, 29 Apr 2026 12:52:37 -0700
Subject: [PATCH] feat: add notification function

---
 config_example.lua    |  5 +++++
 dns.d.lua             |  1 +
 lua-libraries/http.go | 44 +++++++++++++++++++++++++++++++++++++++++++
 lua.go                |  9 +++++++++
 process_cloudflare.go |  1 +
 5 files changed, 60 insertions(+)

diff --git a/config_example.lua b/config_example.lua
index 4e20db6..4589d4a 100644
--- a/config_example.lua
+++ b/config_example.lua
@@ -20,5 +20,10 @@ dns.get_ipv4 = function()
 	return ""
 end
 
+dns.notify = function(domain, old, new)
+	local message = domain .. "has new ip: " .. new
+	http.post("https://ntfy.sh/test-topic-dynamic-dns", message)
+end
+
 -- Interval to update the DNS records
 dns.interval = 4 * time.duration.hour
diff --git a/dns.d.lua b/dns.d.lua
index 0f06382..73c212f 100644
--- a/dns.d.lua
+++ b/dns.d.lua
@@ -4,6 +4,7 @@
 ---@field cloudflare table
 ---@field interval number
 ---@field get_ipv4 function
+---@field notify function
 dns = {}
 
 
diff --git a/lua-libraries/http.go b/lua-libraries/http.go
index 12d6fdd..7ad07eb 100644
--- a/lua-libraries/http.go
+++ b/lua-libraries/http.go
@@ -1,6 +1,7 @@
 package lualibraries
 
 import (
+	"bytes"
 	"io"
 	"net/http"
 
@@ -47,6 +48,49 @@ var httpFunctions = []lua.RegistryFunction{
 
 		return 2
 	}},
+
+	{Name: "post", Function: func(l *lua.State) int {
+		url := lua.CheckString(l, 1)
+		body_content := lua.CheckString(l, 2)
+
+		body := bytes.NewBufferString(body_content)
+
+		req, err := http.NewRequest("POST", url, body)
+		if err != nil {
+			lua.Errorf(l, "unable to build new request: %s", err.Error())
+			return 0
+		}
+
+		if !l.IsNil(3) {
+			headers, err := util.PullStringTable(l, 3)
+			if err != nil {
+				lua.Errorf(l, "unable to acces headers table: %s", err.Error())
+				return 0
+			}
+			for key, value := range headers {
+				req.Header.Set(key, value)
+			}
+		}
+
+		resp, err := http.DefaultClient.Do(req)
+		if err != nil {
+			l.PushString("")
+			l.PushInteger(400)
+			return 2
+		}
+		defer resp.Body.Close()
+		b, err := io.ReadAll(resp.Body)
+		if err != nil {
+			l.PushString("")
+			l.PushInteger(400)
+			return 2
+		}
+
+		l.PushString(string(b))
+		l.PushInteger(resp.StatusCode)
+		return 2
+
+	}},
 }
 
 func LoadHTTP(l *lua.State, global bool) {
diff --git a/lua.go b/lua.go
index c4137e8..e6da0f5 100644
--- a/lua.go
+++ b/lua.go
@@ -36,6 +36,15 @@ func FetchConfigIPv4(l *lua.State) (string, error) {
 	return ip, nil
 }
 
+func Notify(l *lua.State, domain string, oldIP string, newIP string) {
+	l.Global("dns")
+	l.Field(-1, "notify")
+	l.PushString(domain)
+	l.PushString(oldIP)
+	l.PushString(newIP)
+	l.Call(2, 0)
+}
+
 func GetConfigInterval(l *lua.State) time.Duration {
 	l.Global("dns")
 	l.Field(-1, "interval")
diff --git a/process_cloudflare.go b/process_cloudflare.go
index 5b8a9b8..bea2fc7 100644
--- a/process_cloudflare.go
+++ b/process_cloudflare.go
@@ -82,6 +82,7 @@ func startCloudflareConfig(ctx context.Context, l *lua.State, config map[string]
 							log.Printf("error changing record for %s: %s\n", record.Name, err.Error())
 							continue
 						}
+						Notify(l, record.Name, record.Content, ipv4Address)
 						records[i].Content = res.Content
 					}
 				}
-- 
2.51.2