Feature: Web UI notifications of smtpd & POP3 errors (#347)

server/pop3/functions.go

@@ -9,6 +9,7 @@ import (
 	"github.com/axllent/mailpit/internal/auth"
 	"github.com/axllent/mailpit/internal/logger"
 	"github.com/axllent/mailpit/internal/storage"
+	"github.com/axllent/mailpit/server/websockets"
 )
 
 func authUser(username, password string) bool {
@@ -19,6 +20,11 @@ func authUser(username, password string) bool {
 func sendResponse(c net.Conn, m string) {
 	fmt.Fprintf(c, "%s\r\n", m)
 	logger.Log().Debugf("[pop3] response: %s", m)
+
+	if strings.HasPrefix(m, "-ERR ") {
+		sub, _ := strings.CutPrefix(m, "-ERR ")
+		websockets.BroadCastClientError("error", "pop3", c.RemoteAddr().String(), sub)
+	}
 }
 
 // Send a response without debug logging (for data)

server/smtpd/smtpd.go

@@ -14,6 +14,7 @@ import (
 	"github.com/axllent/mailpit/internal/logger"
 	"github.com/axllent/mailpit/internal/stats"
 	"github.com/axllent/mailpit/internal/storage"
+	"github.com/axllent/mailpit/server/websockets"
 	"github.com/lithammer/shortuuid/v4"
 	"github.com/mhale/smtpd"
 )
@@ -22,7 +23,8 @@ var (
 	// DisableReverseDNS allows rDNS to be disabled
 	DisableReverseDNS bool
 
-	errorResponse = regexp.MustCompile(`^[45]\d\d `)
+	warningResponse = regexp.MustCompile(`^4\d\d `)
+	errorResponse   = regexp.MustCompile(`^5\d\d `)
 )
 
 // MailHandler handles the incoming message to store in the database
@@ -237,8 +239,12 @@ func listenAndServe(addr string, handler smtpd.MsgIDHandler, authHandler smtpd.A
 			logger.Log().Debugf("[smtpd] %s (%s) %s", verbLogTranslator(verb), remoteIP, line)
 		},
 		LogWrite: func(remoteIP, verb, line string) {
-			if errorResponse.MatchString(line) {
+			if warningResponse.MatchString(line) {
 				logger.Log().Warnf("[smtpd] %s (%s) %s", verbLogTranslator(verb), remoteIP, line)
+				websockets.BroadCastClientError("warning", "smtpd", remoteIP, line)
+			} else if errorResponse.MatchString(line) {
+				logger.Log().Errorf("[smtpd] %s (%s) %s", verbLogTranslator(verb), remoteIP, line)
+				websockets.BroadCastClientError("error", "smtpd", remoteIP, line)
 			} else {
 				logger.Log().Debugf("[smtpd] %s (%s) %s", verbLogTranslator(verb), remoteIP, line)
 			}

server/ui-src/components/Notifications.vue

@@ -21,6 +21,7 @@ export default {
 			socketBreaks: 0, // to track sockets that continually connect & disconnect, reset every 15s
 			pauseNotifications: false, // prevent spamming
 			version: false,
+			clientErrors: [], // errors received via websocket 
 		}
 	},
 
@@ -39,6 +40,8 @@ export default {
 		mailbox.notificationsSupported = window.isSecureContext
 			&& ("Notification" in window && Notification.permission !== "denied")
 		mailbox.notificationsEnabled = mailbox.notificationsSupported && Notification.permission == "granted"
+
+		this.errorNotificationCron()
 	},
 
 	methods: {
@@ -99,6 +102,9 @@ export default {
 				} else if (response.Type == "truncate") {
 					// broadcast for components
 					this.eventBus.emit("truncate")
+				} else if (response.Type == "error") {
+					// broadcast for components
+					this.addClientError(response.Data)
 				}
 			}
 
@@ -195,12 +201,43 @@ export default {
 				Toast.getOrCreateInstance(el).hide()
 			}
 		},
+
+		addClientError(d) {
+			d.expire = Date.now() + 5000 // expire after 5s
+			this.clientErrors.push(d)
+		},
+
+		errorNotificationCron() {
+			window.setTimeout(() => {
+				this.clientErrors.forEach((err, idx) => {
+					if (err.expire < Date.now()) {
+						this.clientErrors.splice(idx, 1)
+					}
+				})
+				this.errorNotificationCron()
+			}, 1000)
+		}
 	},
 }
 </script>
 
 <template>
 	<div class="toast-container position-fixed bottom-0 end-0 p-3">
+		<div v-for="error in clientErrors" class="toast show" role="alert" aria-live="assertive" aria-atomic="true">
+			<div class="toast-header">
+				<svg class="bd-placeholder-img rounded me-2" width="20" height="20" xmlns="http://www.w3.org/2000/svg"
+					aria-hidden="true" preserveAspectRatio="xMidYMid slice" focusable="false">
+					<rect width="100%" height="100%" :fill="error.Level == 'warning' ? '#ffc107' : '#dc3545'"></rect>
+				</svg>
+				<strong class="me-auto">{{ error.Type }}</strong>
+				<small class="text-body-secondary">{{ error.IP }}</small>
+				<button type="button" class="btn-close" data-bs-dismiss="toast" aria-label="Close"></button>
+			</div>
+			<div class="toast-body">
+				{{ error.Message }}
+			</div>
+		</div>
+
 		<div id="messageToast" class="toast" role="alert" aria-live="assertive" aria-atomic="true">
 			<div class="toast-header" v-if="toastMessage">
 				<i class="bi bi-envelope-exclamation-fill me-2"></i>

server/websockets/hub.go

@@ -90,3 +90,20 @@ func Broadcast(t string, msg interface{}) {
 
 	go func() { MessageHub.Broadcast <- b }()
 }
+
+// BroadCastClientError is a wrapper to broadcast client errors to the web UI
+func BroadCastClientError(severity, errorType, ip, message string) {
+	msg := struct {
+		Level   string
+		Type    string
+		IP      string
+		Message string
+	}{
+		severity,
+		errorType,
+		ip,
+		message,
+	}
+
+	Broadcast("error", msg)
+}