1 files changed, 25 insertions, 1 deletions
diff --git a/packages/taler-util/src/http-client/utils.ts b/packages/taler-util/src/http-client/utils.ts
index d6623cf00..c579cd852 100644
--- a/packages/taler-util/src/http-client/utils.ts
+++ b/packages/taler-util/src/http-client/utils.ts
@@ -18,7 +18,7 @@
  * Imports.
  */
 import { base64FromArrayBuffer } from "../base64.js";
-import { stringToBytes } from "../taler-crypto.js";
+import { encodeCrock, getRandomBytes, stringToBytes } from "../taler-crypto.js";
 import { AccessToken, LongPollParams, PaginationParams } from "./types.js";
 
 /**
@@ -90,3 +90,27 @@ export interface CacheEvictor<T> {
 export const nullEvictor: CacheEvictor<unknown> = {
   notifySuccess: () => Promise.resolve(),
 };
+
+export class IdempotencyRetry {
+  public readonly uid: string;
+  public readonly timesLeft: number;
+  public readonly maxTries: number;
+
+  private constructor(timesLeft: number, maxTimesLeft: number) {
+    this.timesLeft = timesLeft;
+    this.maxTries = maxTimesLeft;
+    this.uid = encodeCrock(getRandomBytes(32))
+  }
+  
+  static tryFiveTimes() {
+    return new IdempotencyRetry(5, 5)
+  }
+
+  next(): IdempotencyRetry | undefined {
+    const left = this.timesLeft -1
+    if (left <= 0) {
+      return undefined
+    }
+    return new IdempotencyRetry(left, this.maxTries);
+  }
+}