feat: support retryDelay

README.md

@@ -99,9 +99,7 @@ await ofetch('/url', { ignoreResponseError: true })
 
 ## ✔️ Auto Retry
 
-`ofetch` Automatically retries the request if an error happens and if response status code is included in `retryStatusCodes` list.
-
-Default is `1` retry, except for `POST`, `PUT`, `PATCH` and `DELETE` methods ofetch does not retry.
+`ofetch` Automatically retries the request if an error happens and if response status code is included in `retryStatusCodes` list:
 
 **Retry status codes:**
 
@@ -114,9 +112,16 @@ Default is `1` retry, except for `POST`, `PUT`, `PATCH` and `DELETE` methods ofe
 - `503` - Service Unavailable
 - `504` - Gateway Timeout
 
+You can specifcy amount of retires and delay between them using `retry` and `retryDelay` options.
+
+Default for `retry` is `1` retry, except for `POST`, `PUT`, `PATCH` and `DELETE` methods ofetch does not retry.
+
+Default for `retryDelay` is zero ms.
+
 ```ts
 await ofetch('http://google.com/404', {
-  retry: 3
+  retry: 3,
+  retryDelay: 500 // ms
 })
 ```
 

src/fetch.ts

@@ -46,6 +46,9 @@ export interface FetchOptions<R extends ResponseType = ResponseType>
   response?: boolean;
   retry?: number | false;
 
+  /** Delay between retries in milliseconds. */
+  retryDelay?: number;
+
   onRequest?(context: FetchContext): Promise<void> | void;
   onRequestError?(
     context: FetchContext & { error: Error }
@@ -86,7 +89,7 @@ const retryStatusCodes = new Set([
 export function createFetch(globalOptions: CreateFetchOptions): $Fetch {
   const { fetch, Headers } = globalOptions;
 
-  function onError(context: FetchContext): Promise<FetchResponse<any>> {
+  async function onError(context: FetchContext): Promise<FetchResponse<any>> {
     // Is Abort
     // If it is an active abort, it will not retry automatically.
     // https://developer.mozilla.org/en-US/docs/Web/API/DOMException#error_names
@@ -103,6 +106,10 @@ export function createFetch(globalOptions: CreateFetchOptions): $Fetch {
 
       const responseCode = (context.response && context.response.status) || 500;
       if (retries > 0 && retryStatusCodes.has(responseCode)) {
+        const retryDelay = context.options.retryDelay || 0;
+        if (retryDelay > 0) {
+          await new Promise((resolve) => setTimeout(resolve, retryDelay));
+        }
         return $fetchRaw(context.request, {
           ...context.options,
           retry: retries - 1,

test/index.test.ts

@@ -61,7 +61,12 @@ describe("ofetch", () => {
         eventHandler(() =>
           createError({ status: 403, statusMessage: "Forbidden" })
         )
+      )
+      .use(
+        "/408",
+        eventHandler(() => createError({ status: 408 }))
       );
+
     listener = await listen(toNodeListener(app));
   });
 
@@ -135,7 +140,7 @@ describe("ofetch", () => {
       const { headers } = await $fetch(getURL("post"), {
         method: "POST",
         body: { num: 42 },
-        headers: sentHeaders,
+        headers: sentHeaders as HeadersInit,
       });
       expect(headers).to.include({ "x-header": "1" });
       expect(headers).to.include({ accept: "application/json" });
@@ -196,6 +201,20 @@ describe("ofetch", () => {
     expect(error.request).to.equal(getURL("404"));
   });
 
+  it("retry with delay", async () => {
+    const slow = $fetch<string>(getURL("408"), {
+      retry: 2,
+      retryDelay: 100,
+    }).catch(() => "slow");
+    const fast = $fetch<string>(getURL("408"), {
+      retry: 2,
+      retryDelay: 1,
+    }).catch(() => "fast");
+
+    const race = await Promise.race([slow, fast]);
+    expect(race).to.equal("fast");
+  });
+
   it("abort with retry", () => {
     const controller = new AbortController();
     async function abortHandle() {