Add tool to check XMPP certificate on starttls

Minor refactoring

cmd/xmpp-check/TODO.md

@@ -0,0 +1,3 @@
+# TODO
+
+- Use a config file to define the checks to perform as client on an XMPP server.

cmd/xmpp-check/xmpp-check.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"log"
+	"os"
+
+	"gosrc.io/xmpp"
+)
+
+func main() {
+	args := os.Args[1:]
+
+	if len(args) == 0 {
+		log.Fatal("usage: xmpp-check host[:port] [domain]")
+	}
+
+	var address string
+	var domain string
+	if len(args) >= 1 {
+		address = args[0]
+	}
+
+	if len(args) >= 2 {
+		domain = args[1]
+	}
+
+	runCheck(address, domain)
+}
+
+func runCheck(address, domain string) {
+	client, err := xmpp.NewChecker(address, domain)
+	// client, err := xmpp.NewChecker("mickael.m.in-app.io:5222", "mickael.m.in-app.io")
+
+	if err != nil {
+		log.Fatal("Error: ", err)
+	}
+
+	if err = client.Check(); err != nil {
+		log.Fatal("Failed connection check: ", err)
+	}
+
+	log.Println("All checks passed")
+}