feat: add ntfy integration (#2900)

Co-authored-by: Meier Lukas <meierschlumpf@gmail.com>

packages/integrations/src/ntfy/ntfy-integration.ts

@@ -0,0 +1,65 @@
+import { fetchWithTrustedCertificatesAsync } from "@homarr/certificates/server";
+import { ResponseError } from "@homarr/common/server";
+
+import type { IntegrationTestingInput } from "../base/integration";
+import type { TestingResult } from "../base/test-connection/test-connection-service";
+import type { Notification } from "../interfaces/notifications/notification";
+import { NotificationsIntegration } from "../interfaces/notifications/notifications-integration";
+import { ntfyNotificationSchema } from "./ntfy-schema";
+
+export class NTFYIntegration extends NotificationsIntegration {
+  public async testingAsync(input: IntegrationTestingInput): Promise<TestingResult> {
+    await input.fetchAsync(this.url("/v1/account"), { headers: this.getHeaders() });
+    return { success: true };
+  }
+
+  private getTopicURL() {
+    return this.url(`/${encodeURIComponent(super.getSecretValue("topic"))}/json`, { poll: 1 });
+  }
+  private getHeaders() {
+    return this.hasSecretValue("apiKey") ? { Authorization: `Bearer ${super.getSecretValue("apiKey")}` } : {};
+  }
+
+  public async getNotificationsAsync() {
+    const url = this.getTopicURL();
+    const notifications = await Promise.all(
+      (
+        await fetchWithTrustedCertificatesAsync(url, { headers: this.getHeaders() })
+          .then((response) => {
+            if (!response.ok) throw new ResponseError(response);
+            return response.text();
+          })
+          .catch((error) => {
+            if (error instanceof Error) throw error;
+            else {
+              throw new Error("Error communicating with ntfy");
+            }
+          })
+      )
+        // response is provided as individual lines of JSON
+        .split("\n")
+        .map(async (line) => {
+          // ignore empty lines
+          if (line.length === 0) return null;
+
+          const json = JSON.parse(line) as unknown;
+          const parsed = await ntfyNotificationSchema.parseAsync(json);
+          if (parsed.event === "message") return parsed;
+          // ignore non-event messages
+          else return null;
+        }),
+    );
+
+    return notifications
+      .filter((notification) => notification !== null)
+      .map((notification): Notification => {
+        const topicURL = this.url(`/${notification.topic}`);
+        return {
+          id: notification.id,
+          time: new Date(notification.time * 1000),
+          title: notification.title ?? topicURL.hostname + topicURL.pathname,
+          body: notification.message,
+        };
+      });
+  }
+}

packages/integrations/src/ntfy/ntfy-schema.ts

@@ -0,0 +1,12 @@
+import { z } from "zod";
+
+// There are more properties, see: https://docs.ntfy.sh/subscribe/api/#json-message-format
+// Not all properties are required for this use case.
+export const ntfyNotificationSchema = z.object({
+  id: z.string(),
+  time: z.number(),
+  event: z.string(), // we only care about "message"
+  topic: z.string(),
+  title: z.optional(z.string()),
+  message: z.string(),
+});