2 files changed, 30 insertions, 1 deletions
diff --git a/packages/demobank-ui/src/hooks/backend.ts b/packages/demobank-ui/src/hooks/backend.ts
index 3eaf1f186..851a3fb5b 100644
--- a/packages/demobank-ui/src/hooks/backend.ts
+++ b/packages/demobank-ui/src/hooks/backend.ts
@@ -16,6 +16,7 @@
 
 import { canonicalizeBaseUrl } from "@gnu-taler/taler-util";
 import {
+  ErrorType,
   RequestError,
   useLocalStorage,
 } from "@gnu-taler/web-util/lib/index.browser";
@@ -192,6 +193,33 @@ export function usePublicBackend(): useBackendType {
   };
 }
 
+export function useCredentialsChecker() {
+  const { request } = useApiContext();
+  const baseUrl = getInitialBackendBaseURL();
+  //check against account details endpoint
+  //while sandbox backend doesn't have a login endpoint
+  return async function testLogin(
+    username: string,
+    password: string,
+  ): Promise<{
+    valid: boolean;
+    cause?: ErrorType;
+  }> {
+    try {
+      await request(baseUrl, `access-api/accounts/${username}/`, {
+        basicAuth: { username, password },
+        preventCache: true,
+      });
+      return { valid: true };
+    } catch (error) {
+      if (error instanceof RequestError) {
+        return { valid: false, cause: error.cause.type };
+      }
+      return { valid: false, cause: ErrorType.UNEXPECTED };
+    }
+  };
+}
+
 export function useAuthenticatedBackend(): useBackendType {
   const { state } = useBackendContext();
   const { request: requestHandler } = useApiContext();
diff --git a/packages/demobank-ui/src/hooks/circuit.ts b/packages/demobank-ui/src/hooks/circuit.ts
index 548862d85..137a7aee2 100644
--- a/packages/demobank-ui/src/hooks/circuit.ts
+++ b/packages/demobank-ui/src/hooks/circuit.ts
@@ -288,9 +288,10 @@ export function useRatiosAndFeeConfig(): HttpResponse<
     HttpResponseOk<SandboxBackend.Circuit.Config>,
     RequestError<SandboxBackend.SandboxError>
   >([`circuit-api/config`], fetcher, {
-    refreshInterval: 1000,
+    refreshInterval: 60 * 1000,
     refreshWhenHidden: false,
     revalidateOnFocus: false,
+    revalidateIfStale: false,
     revalidateOnReconnect: false,
     refreshWhenOffline: false,
     errorRetryCount: 0,