add support heartbeat to couchdb-changes-stream

services/message-delivery-method-web-push/src/serviceSeqTracker.ts

@@ -1,28 +1,32 @@
 import { serviceDb, type ServiceDoc } from "./dbs";
 
-const SERVICE_DOC_ID = "_local/service:message-delivery-method-web-push";
-
 export class ServiceSeqTracker {
-  private serviceDoc: ServiceDoc;
-
-  async getSince() {
-    this.serviceDoc = await serviceDb.get(SERVICE_DOC_ID).catch((error) => {
+  /**
+   * @param _id
+   * @constructor
+   */
+  static async Init(_id: string) {
+    const serviceDoc = await serviceDb.get(_id).catch((error) => {
       if (error.name === "not_found") {
         return {
-          _id: SERVICE_DOC_ID,
+          _id,
           lastSeq: "0",
         };
       }
       throw error; // Re-throw other errors
     });
+    return new ServiceSeqTracker(serviceDoc);
+  }
 
-    // this.serviceDoc.lastSeq =
-    //   "126-g1AAAACLeJzLYWBgYMpgTmHgzcvPy09JdcjLz8gvLskBCScyJNX___8_K4M50SUXKMCebGlpnmxpiq4Yh_Y8FiDJ0ACk_kNNsQKbYpSakphkYYKuJwsAb2YrPw";
+  private constructor(private serviceDoc: ServiceDoc) {}
 
+  get lastSeq() {
     return this.serviceDoc.lastSeq;
   }
 
   checkNextSeq(seq: number | string) {
+    if (!this.serviceDoc) {
+    }
     const next = parseInt(seq as string, 10);
     const current = parseInt(this.serviceDoc.lastSeq as string, 10);
     if (next < current) {