More refactoring based on feedback

frontend/src/app/services/preload.service.ts

@@ -0,0 +1,33 @@
+import { Injectable } from '@angular/core';
+import { ElectrsApiService } from '../services/electrs-api.service';
+import { Subject, debounceTime, switchMap } from 'rxjs';
+import { ApiService } from './api.service';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class PreloadService {
+  block$ = new Subject<string>;
+  blockAudit$ = new Subject<string>;
+  debounceTime = 250;
+
+  constructor(
+    private electrsApiService: ElectrsApiService,
+    private apiService: ApiService,
+  ) {
+    this.block$
+      .pipe(
+        debounceTime(this.debounceTime),
+        switchMap((blockHash) => this.electrsApiService.getBlockTransactions$(blockHash))
+      )
+      .subscribe();
+
+    this.blockAudit$
+      .pipe(
+        debounceTime(this.debounceTime),
+        switchMap((blockHash) => this.apiService.getBlockAudit$(blockHash))
+      )
+      .subscribe();
+  }
+
+}