F

src/shared/api/csrf.ts

@@ -6,17 +6,28 @@ interface CsrfResponse {
 }
 
 let cachedToken: string | null = null
+let inflight: Promise<string> | null = null
 
 export function clearCsrfCache(): void {
   cachedToken = null
+  inflight = null
 }
 
-export async function getCsrfToken(): Promise<string> {
-  if (cachedToken) return cachedToken
-  const res = await fetch(`${API_URL}/csrf/token`, {
-    credentials: 'include',
-  })
-  const data: CsrfResponse = await res.json()
-  cachedToken = data.token
-  return cachedToken
+export function getCsrfToken(): Promise<string> {
+  if (cachedToken) return Promise.resolve(cachedToken)
+  if (inflight) return inflight
+
+  inflight = fetch(`${API_URL}/csrf/token`, { credentials: 'include' })
+    .then((res) => res.json() as Promise<CsrfResponse>)
+    .then((data) => {
+      cachedToken = data.token
+      inflight = null
+      return cachedToken
+    })
+    .catch((err) => {
+      inflight = null
+      throw err
+    })
+
+  return inflight
 }