feat(notifications): add Telegram notification channel (#2753)

Add Telegram as a new notification type, allowing users to receive
monitor alerts via a Telegram bot.

Configuration requires:
- Bot token (obtained from @BotFather)
- Chat ID (user, group, or channel)

Changes:
- TelegramProvider: sends HTML-formatted messages via Telegram Bot API
- NotificationsService: route telegram type to TelegramProvider
- Notification model/types: add 'telegram' to NotificationChannel enum
- Server validation: telegram schema (accessToken + address/chat_id)
- Client Types/Validation: telegram schema with accessToken + address
- useNotificationForm: handle telegram defaults
- Notifications create page: render Telegram config UI
- en.json: add telegram i18n keys

client/src/Hooks/useNotificationForm.ts

@@ -17,11 +17,18 @@ export const useNotificationForm = ({ data = null }: UseNotificationFormOptions
 						roomId: data.roomId || "",
 						accessToken: data.accessToken || "",
 					}
-				: {
-						type: (data?.type || "email") as Exclude<Notification["type"], "matrix">,
-						notificationName: data?.notificationName || "",
-						address: data?.address || "",
-					};
+				: data?.type === "telegram"
+					? {
+							type: "telegram" as const,
+							notificationName: data.notificationName || "",
+							address: data.address || "",
+							accessToken: data.accessToken || "",
+						}
+					: {
+							type: (data?.type || "email") as Exclude<Notification["type"], "matrix" | "telegram">,
+							notificationName: data?.notificationName || "",
+							address: data?.address || "",
+						};
 
 		return { schema: notificationSchema, defaults };
 	}, [data]);

client/src/Pages/Notifications/create/index.tsx

@@ -147,7 +147,7 @@ const NotificationsCreatePage = () => {
 					/>
 				}
 			/>
-			{watchedType !== "matrix" && (
+			{watchedType !== "matrix" && watchedType !== "telegram" && (
 				<ConfigBox
 					title={addressConfig.title}
 					subtitle={addressConfig.description}
@@ -171,6 +171,48 @@ const NotificationsCreatePage = () => {
 					}
 				/>
 			)}
+			{watchedType === "telegram" && (
+				<ConfigBox
+					title={t("pages.notifications.form.telegram.title")}
+					subtitle={t("pages.notifications.form.telegram.description")}
+					rightContent={
+						<Stack spacing={theme.spacing(8)}>
+							<Controller
+								name="accessToken"
+								control={control}
+								defaultValue={defaults.accessToken}
+								render={({ field, fieldState }) => (
+									<TextField
+										{...field}
+										type="text"
+										fieldLabel={t("pages.notifications.form.telegram.optionBotToken")}
+										placeholder={t("pages.notifications.form.telegram.placeholderBotToken")}
+										fullWidth
+										error={!!fieldState.error}
+										helperText={fieldState.error?.message ?? ""}
+									/>
+								)}
+							/>
+							<Controller
+								name="address"
+								control={control}
+								defaultValue={defaults.address}
+								render={({ field, fieldState }) => (
+									<TextField
+										{...field}
+										type="text"
+										fieldLabel={t("pages.notifications.form.telegram.optionChatId")}
+										placeholder={t("pages.notifications.form.telegram.placeholderChatId")}
+										fullWidth
+										error={!!fieldState.error}
+										helperText={fieldState.error?.message ?? ""}
+									/>
+								)}
+							/>
+						</Stack>
+					}
+				/>
+			)}
 			{watchedType === "matrix" && (
 				<ConfigBox
 					title={t("pages.notifications.form.matrix.title")}

client/src/Types/Notification.ts

@@ -6,6 +6,7 @@ export const NotificationChannels = [
 	"pager_duty",
 	"matrix",
 	"teams",
+	"telegram",
 ] as const;
 export type NotificationChannel = (typeof NotificationChannels)[number];
 

client/src/Validation/notifications.ts

@@ -50,6 +50,12 @@ const teamsSchema = baseSchema.extend({
 	address: z.string().min(1, "Webhook URL is required").url("Please enter a valid URL"),
 });
 
+const telegramSchema = baseSchema.extend({
+	type: z.literal("telegram"),
+	address: z.string().min(1, "Chat ID is required"),
+	accessToken: z.string().min(1, "Bot token is required"),
+});
+
 export const notificationSchema = z.discriminatedUnion("type", [
 	emailSchema,
 	slackSchema,
@@ -58,6 +64,7 @@ export const notificationSchema = z.discriminatedUnion("type", [
 	pagerDutySchema,
 	matrixSchema,
 	teamsSchema,
+	telegramSchema,
 ]);
 
 export type NotificationFormData = z.infer<typeof notificationSchema>;

server/src/config/services.ts

@@ -28,6 +28,7 @@ import {
 	PagerDutyProvider,
 	MatrixProvider,
 	TeamsProvider,
+	TelegramProvider,
 	// Interfaces
 	INetworkService,
 	IEmailService,
@@ -230,6 +231,7 @@ export const initializeServices = async ({
 	const pagerDutyProvider = new PagerDutyProvider(logger);
 	const matrixProvider = new MatrixProvider(logger);
 	const teamsProvider = new TeamsProvider(logger);
+	const telegramProvider = new TelegramProvider(logger);
 
 	const notificationsService = new NotificationsService(
 		notificationsRepository,
@@ -241,6 +243,7 @@ export const initializeServices = async ({
 		pagerDutyProvider,
 		matrixProvider,
 		teamsProvider,
+		telegramProvider,
 		settingsService,
 		logger,
 		notificationMessageBuilder

server/src/db/models/Notification.ts

@@ -25,7 +25,7 @@ const NotificationSchema = new Schema<NotificationDocument>(
 		},
 		type: {
 			type: String,
-			enum: ["email", "slack", "discord", "webhook", "pager_duty", "matrix", "teams"] as NotificationChannel[],
+			enum: ["email", "slack", "discord", "webhook", "pager_duty", "matrix", "teams", "telegram"] as NotificationChannel[],
 			required: true,
 		},
 		notificationName: {

server/src/service/index.ts

@@ -29,6 +29,7 @@ export * from "@/service/infrastructure/notificationProviders/pagerduty.js";
 export * from "@/service/infrastructure/notificationProviders/slack.js";
 export * from "@/service/infrastructure/notificationProviders/teams.js";
 export * from "@/service/infrastructure/notificationProviders/webhook.js";
+export * from "@/service/infrastructure/notificationProviders/telegram.js";
 
 // System services
 export * from "@/service/system/settingsService.js";

server/src/service/infrastructure/notificationProviders/telegram.ts

@@ -0,0 +1,109 @@
+const SERVICE_NAME = "TelegramProvider";
+import type { Notification } from "@/types/index.js";
+import { INotificationProvider } from "@/service/index.js";
+import type { NotificationMessage } from "@/types/notificationMessage.js";
+import { getTestMessage } from "@/service/infrastructure/notificationProviders/utils.js";
+import got, { HTTPError } from "got";
+import { ILogger } from "@/utils/logger.js";
+
+export class TelegramProvider implements INotificationProvider {
+	private logger: ILogger;
+
+	constructor(logger: ILogger) {
+		this.logger = logger;
+	}
+
+	async sendTestAlert(notification: Partial<Notification>): Promise<boolean> {
+		if (!notification.address || !notification.accessToken) {
+			return false;
+		}
+
+		try {
+			await got.post(`https://api.telegram.org/bot${notification.accessToken}/sendMessage`, {
+				json: {
+					chat_id: notification.address,
+					text: getTestMessage(),
+					parse_mode: "HTML",
+				},
+			});
+			return true;
+		} catch (error) {
+			const err = error as HTTPError;
+			this.logger.warn({
+				message: "Telegram test alert failed",
+				service: SERVICE_NAME,
+				method: "sendTestAlert",
+				stack: err?.stack,
+			});
+			return false;
+		}
+	}
+
+	async sendMessage(notification: Notification, message: NotificationMessage): Promise<boolean> {
+		if (!notification.address || !notification.accessToken) {
+			return false;
+		}
+
+		const text = this.buildTelegramText(message);
+
+		try {
+			await got.post(`https://api.telegram.org/bot${notification.accessToken}/sendMessage`, {
+				json: {
+					chat_id: notification.address,
+					text,
+					parse_mode: "HTML",
+				},
+			});
+			this.logger.info({
+				message: "Telegram notification sent",
+				service: SERVICE_NAME,
+				method: "sendMessage",
+			});
+			return true;
+		} catch (error) {
+			const err = error as HTTPError;
+			this.logger.warn({
+				message: "Telegram alert failed",
+				service: SERVICE_NAME,
+				method: "sendMessage",
+				stack: err?.stack,
+			});
+			return false;
+		}
+	}
+
+	private buildTelegramText(message: NotificationMessage): string {
+		const lines: string[] = [];
+
+		lines.push(`<b>${message.content.title}</b>`);
+		lines.push(message.content.summary);
+		lines.push("");
+
+		lines.push("<b>Monitor Details:</b>");
+		lines.push(`• Name: ${message.monitor.name}`);
+		lines.push(`• URL: ${message.monitor.url}`);
+		lines.push(`• Type: ${message.monitor.type}`);
+		lines.push(`• Status: ${message.monitor.status}`);
+
+		if (message.content.details && message.content.details.length > 0) {
+			lines.push("");
+			lines.push("<b>Additional Information:</b>");
+			message.content.details.forEach((detail) => lines.push(`• ${detail}`));
+		}
+
+		if (message.content.thresholds && message.content.thresholds.length > 0) {
+			lines.push("");
+			lines.push("<b>Threshold Breaches:</b>");
+			message.content.thresholds.forEach((breach) => {
+				lines.push(`• ${breach.metric.toUpperCase()}: ${breach.formattedValue} (threshold: ${breach.threshold}${breach.unit})`);
+			});
+		}
+
+		if (message.content.incident) {
+			lines.push("");
+			lines.push(`<a href="${message.clientHost}/infrastructure/${message.monitor.id}">View Incident</a>`);
+		}
+
+		return lines.join("\n");
+	}
+}

server/src/service/infrastructure/notificationsService.ts

@@ -33,6 +33,7 @@ export class NotificationsService implements INotificationsService {
 	private pagerDutyProvider: INotificationProvider;
 	private matrixProvider: INotificationProvider;
 	private teamsProvider: INotificationProvider;
+	private telegramProvider: INotificationProvider;
 	private logger: ILogger;
 	private settingsService: ISettingsService;
 	private notificationMessageBuilder: INotificationMessageBuilder;
@@ -47,6 +48,7 @@ export class NotificationsService implements INotificationsService {
 		pagerDutyProvider: INotificationProvider,
 		matrixProvider: INotificationProvider,
 		teamsProvider: INotificationProvider,
+		telegramProvider: INotificationProvider,
 		settingsService: ISettingsService,
 		logger: ILogger,
 		notificationMessageBuilder: INotificationMessageBuilder
@@ -60,6 +62,7 @@ export class NotificationsService implements INotificationsService {
 		this.pagerDutyProvider = pagerDutyProvider;
 		this.matrixProvider = matrixProvider;
 		this.teamsProvider = teamsProvider;
+		this.telegramProvider = telegramProvider;
 		this.settingsService = settingsService;
 		this.logger = logger;
 		this.notificationMessageBuilder = notificationMessageBuilder;
@@ -97,6 +100,8 @@ export class NotificationsService implements INotificationsService {
 				return await this.emailProvider.sendMessage!(notification, notificationMessage);
 			case "teams":
 				return await this.teamsProvider.sendMessage!(notification, notificationMessage);
+			case "telegram":
+				return await this.telegramProvider.sendMessage!(notification, notificationMessage);
 			default:
 				this.logger.warn({
 					message: `Unknown notification type: ${notification.type}`,
@@ -157,6 +162,8 @@ export class NotificationsService implements INotificationsService {
 				return await this.webhookProvider.sendTestAlert(notification);
 			case "teams":
 				return await this.teamsProvider.sendTestAlert(notification);
+			case "telegram":
+				return await this.telegramProvider.sendTestAlert(notification);
 			default:
 				return false;
 		}

server/src/types/notification.ts

@@ -1,4 +1,4 @@
-export const NotificationChannels = ["email", "slack", "discord", "webhook", "pager_duty", "matrix", "teams"] as const;
+export const NotificationChannels = ["email", "slack", "discord", "webhook", "pager_duty", "matrix", "teams", "telegram"] as const;
 export type NotificationChannel = (typeof NotificationChannels)[number];
 
 export interface Notification {

server/src/validation/notificationValidation.ts

@@ -65,6 +65,13 @@ export const createNotificationBodyValidation = z.discriminatedUnion("type", [
 		type: z.literal("teams"),
 		address: z.url({ message: "Please enter a valid Webhook URL" }),
 	}),
+	// Telegram notification
+	z.object({
+		notificationName: z.string().min(1, "Notification name is required"),
+		type: z.literal("telegram"),
+		address: z.string().min(1, "Chat ID is required"),
+		accessToken: z.string().min(1, "Bot token is required"),
+	}),
 ]);
 
 export const testNotificationBodyValidation = createNotificationBodyValidation;