From 94cf8100bada94b2241e64a410859e128c1c6342 Mon Sep 17 00:00:00 2001
From: Bernhard B <bernhard@liftingcoder.com>
Date: Sun, 29 Jun 2025 16:41:38 +0200
Subject: [PATCH] added possibility to call a webhook when a message is
 received

---
 src/client/client.go   |  6 ++++--
 src/client/jsonrpc2.go | 35 ++++++++++++++++++++++++++++++++++-
 src/main.go            |  7 ++++++-
 3 files changed, 44 insertions(+), 4 deletions(-)

diff --git a/src/client/client.go b/src/client/client.go
index a56d956..35077b3 100644
--- a/src/client/client.go
+++ b/src/client/client.go
@@ -370,10 +370,11 @@ type SignalClient struct {
 	signalCliApiConfigPath   string
 	signalCliApiConfig       *utils.SignalCliApiConfig
 	cliClient                *CliClient
+	receiveWebhookUrl        string
 }
 
 func NewSignalClient(signalCliConfig string, attachmentTmpDir string, avatarTmpDir string, signalCliMode SignalCliMode,
-	jsonRpc2ClientConfigPath string, signalCliApiConfigPath string) *SignalClient {
+	jsonRpc2ClientConfigPath string, signalCliApiConfigPath string, receiveWebhookUrl string) *SignalClient {
 	return &SignalClient{
 		signalCliConfig:          signalCliConfig,
 		attachmentTmpDir:         attachmentTmpDir,
@@ -382,6 +383,7 @@ func NewSignalClient(signalCliConfig string, attachmentTmpDir string, avatarTmpD
 		jsonRpc2ClientConfigPath: jsonRpc2ClientConfigPath,
 		jsonRpc2Clients:          make(map[string]*JsonRpc2Client),
 		signalCliApiConfigPath:   signalCliApiConfigPath,
+		receiveWebhookUrl:        receiveWebhookUrl,
 	}
 }
 
@@ -411,7 +413,7 @@ func (s *SignalClient) Init() error {
 				return err
 			}
 
-			go s.jsonRpc2Clients[number].ReceiveData(number) //receive messages in goroutine
+			go s.jsonRpc2Clients[number].ReceiveData(number, s.receiveWebhookUrl) //receive messages in goroutine
 		}
 	} else {
 		s.cliClient = NewCliClient(s.signalCliMode, s.signalCliApiConfig)
diff --git a/src/client/jsonrpc2.go b/src/client/jsonrpc2.go
index 6df5c4b..b2fae23 100644
--- a/src/client/jsonrpc2.go
+++ b/src/client/jsonrpc2.go
@@ -7,6 +7,9 @@ import (
 	"net"
 	"sync"
 	"time"
+	"net/http"
+	"bytes"
+	"strconv"
 
 	"github.com/bbernhard/signal-cli-rest-api/utils"
 	uuid "github.com/gofrs/uuid"
@@ -176,7 +179,30 @@ func (r *JsonRpc2Client) getRaw(command string, account *string, args interface{
 	return string(resp.Result), nil
 }
 
-func (r *JsonRpc2Client) ReceiveData(number string) {
+func postMessageToWebhook(webhookUrl string, data []byte) error {
+	r, err := http.NewRequest("POST", webhookUrl, bytes.NewBuffer(data))
+	if err != nil {
+		return err
+	}
+
+	r.Header.Add("Content-Type", "application/json")
+
+	client := &http.Client{}
+	res, err := client.Do(r)
+	if err != nil {
+		return err
+	}
+
+	defer res.Body.Close()
+
+	log.Info(res.StatusCode)
+	if res.StatusCode != 200 && res.StatusCode != 201 {
+		return errors.New("Unexpected status code returned (" + strconv.Itoa(res.StatusCode) + ")")
+	}
+	return nil
+}
+
+func (r *JsonRpc2Client) ReceiveData(number string, receiveWebhookUrl string) {
 	connbuf := bufio.NewReader(r.conn)
 	for {
 		str, err := connbuf.ReadString('\n')
@@ -190,6 +216,13 @@ func (r *JsonRpc2Client) ReceiveData(number string) {
 		}
 		log.Debug("json-rpc received data: ", str)
 
+		if receiveWebhookUrl != "" {
+			err = postMessageToWebhook(receiveWebhookUrl, []byte(str))
+			if err != nil {
+				log.Error("Couldn't post data to webhook: ", err)
+			}
+		}
+
 		var resp1 JsonRpc2ReceivedMessage
 		json.Unmarshal([]byte(str), &resp1)
 		if resp1.Method == "receive" {
diff --git a/src/main.go b/src/main.go
index 64e1f8d..6398132 100644
--- a/src/main.go
+++ b/src/main.go
@@ -155,9 +155,14 @@ func main() {
 		}
 	}
 
+	webhookUrl := utils.GetEnv("RECEIVE_WEBHOOK_URL", "")
+	if webhookUrl != "" && signalCliMode != client.JsonRpc {
+		log.Fatal("Env variable RECEIVE_WEBHOOK_URL can't be used with mode json-rpc!")
+	}
+
 	jsonRpc2ClientConfigPathPath := *signalCliConfig + "/jsonrpc2.yml"
 	signalCliApiConfigPath := *signalCliConfig + "/api-config.yml"
-	signalClient := client.NewSignalClient(*signalCliConfig, *attachmentTmpDir, *avatarTmpDir, signalCliMode, jsonRpc2ClientConfigPathPath, signalCliApiConfigPath)
+	signalClient := client.NewSignalClient(*signalCliConfig, *attachmentTmpDir, *avatarTmpDir, signalCliMode, jsonRpc2ClientConfigPathPath, signalCliApiConfigPath, webhookUrl)
 	err = signalClient.Init()
 	if err != nil {
 		log.Fatal("Couldn't init Signal Client: ", err.Error())