From 18d46d2c4a58a76b4bfc436f04a94677b5f84f87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kope=C4=8Dek?= <martin.kopecek@smallhill.cz>
Date: Mon, 29 Apr 2024 17:47:23 +0000
Subject: [PATCH] feat: add retryRequest function

---
 frontend/src/app/services/api.service.ts | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/frontend/src/app/services/api.service.ts b/frontend/src/app/services/api.service.ts
index c53b9811..16efa516 100644
--- a/frontend/src/app/services/api.service.ts
+++ b/frontend/src/app/services/api.service.ts
@@ -1,7 +1,7 @@
 import { Injectable } from "@angular/core";
 import axios, { AxiosError, AxiosResponse } from "axios";
-import { BehaviorSubject } from "rxjs";
-import { map } from "rxjs/operators";
+import { BehaviorSubject, defer, fromEvent } from "rxjs";
+import { filter, map, repeat, retry } from "rxjs/operators";
 import { appConfig } from "src/config";
 import { environment } from "src/environments/environment";
 import { Logger } from "src/logger";
@@ -24,6 +24,23 @@ export type ApiError = AxiosError;
 
 axios.defaults.withCredentials = true;
 
+interface RetryRequestOptions {
+  maxRetries?: number;
+  onFocus?: boolean;
+}
+
+const tabFocusEvent = fromEvent(document, "visibilitychange").pipe(
+  filter(() => document.visibilityState === "visible"),
+);
+
+export function retryRequest<T, D>(request: () => Promise<AxiosResponse<T, D>>, options: RetryRequestOptions = {}) {
+  let o = defer(() => request());
+  if (options.maxRetries) o = o.pipe(retry(options.maxRetries));
+  if (options.onFocus) o = o.pipe(repeat({ delay: () => tabFocusEvent }));
+
+  return o;
+}
+
 @Injectable({
   providedIn: "root",
 })