From 1eca8a84b42f126909839d8c640887c846f94424 Mon Sep 17 00:00:00 2001
From: Martin Dosch <spam-debian-salsa@mdosch.de>
Date: Sat, 28 Jul 2018 21:38:48 +0200
Subject: [PATCH] Added check if bot is still joined to MUC.

---
 feed-to-muc.go | 65 +++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 56 insertions(+), 9 deletions(-)

diff --git a/feed-to-muc.go b/feed-to-muc.go
index 437ecb5..f220013 100644
--- a/feed-to-muc.go
+++ b/feed-to-muc.go
@@ -12,6 +12,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/chilts/sid"
 	"github.com/mattn/go-xmpp"
 )
 
@@ -108,14 +109,12 @@ func main() {
 		Debug:    false,
 	}
 
+	// Connect to server.
 	client, err = options.NewClient()
 	if err != nil {
 		log.Fatal(err)
 	}
 
-	// Starting goroutine to ping the server every 30 seconds.
-	go ping(client, config.ServerAddress, config.BotJid)
-
 	// Join the MUC
 	mucStatus, err := client.JoinMUCNoHistory(config.Muc, config.MucNick)
 	if err != nil {
@@ -127,11 +126,13 @@ func main() {
 		os.Exit(mucStatus)
 	}
 
+	// Starting goroutine to ping the server every 30 seconds.
+	go pingServer(client, config.ServerAddress, config.BotJid)
+
+	// Starting goroutine to ping the MUC every 30 seconds.
+	go pingMUC(client, config.BotJid, config.Muc, config.MucNick)
+
 	for {
-		_, err := client.Recv()
-		if err != nil {
-			log.Fatal(err)
-		}
 
 		for i := 0; i < len(config.Feeds); i++ {
 			output, err := getArticles(config.Feeds[i], config.MaxArticles)
@@ -151,13 +152,59 @@ func main() {
 	}
 }
 
-// Send a ping every 30 seconds to check if the server is still available.
-func ping(client *xmpp.Client, server string, botJid string) {
+// Send a ping every 30 seconds after last successful ping to check if the MUC is still available.
+func pingMUC(client *xmpp.Client, botJid string, Muc string, MucNick string) {
 	for {
 		time.Sleep(30 * time.Second)
+
+		// Send ping to own MUC participant to check we are still joined.
+		id, err := client.RawInformation(botJid, Muc+"/"+MucNick, sid.Id(), "get", "<ping xmlns='urn:xmpp:ping'/>")
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		pingSent := time.Now()
+		pingReceived := false
+
+		// Check for result IQ as long as there was no reply yet.
+		for (time.Since(pingSent).Seconds() < 10.0) && (pingReceived == false) {
+			// Receive Stanzas.
+			stanza, err := client.Recv()
+			if err != nil {
+				log.Fatal(err)
+			}
+
+			// Check IQs for type result and UID.
+			switch v := stanza.(type) {
+			case xmpp.IQ:
+				if (v.Type == "error") && (v.ID == id) {
+					log.Fatal("MUC not available.")
+				}
+				if (v.Type == "result") && (v.ID == id) {
+					pingReceived = true
+				}
+				break
+			default:
+				break
+			}
+		}
+		// Quit if no ping reply was received.
+		if pingReceived == false {
+			log.Fatal("MUC not available.")
+		}
+	}
+}
+
+// Send a ping to the server every 30 seconds to check if the connection is still alive.
+func pingServer(client *xmpp.Client, server string, botJid string) {
+	for {
+		time.Sleep(30 * time.Second)
+
+		// Send ping to server to check if connection still exists.
 		err := client.PingC2S(botJid, strings.Split(server, ":")[0])
 		if err != nil {
 			log.Fatal(err)
 		}
 	}
+
 }