fix: let useSubscription reject when onlyOnce fetchFn fails

Author: cabljac

firebase.json

@@ -18,5 +18,8 @@
   },
   "functions": {
     "predeploy": "npm --prefix \"$RESOURCE_DIR\" run build"
+  },
+  "firestore": {
+    "rules": "./firestore.rules"
   }
-}
+}

firestore.rules

@@ -0,0 +1,7 @@
+service cloud.firestore {
+  match /databases/{database}/documents {
+    match /noread/{document=**} {
+      allow read: if false;
+    }
+  }
+} 

package.json

@@ -59,4 +59,4 @@
     "format": "prettier --write ."
   },
   "dependencies": {}
-}
+}

packages/firestore/__test__/useFirestoreDocument.test.ts

@@ -369,6 +369,37 @@ describe("useFirestoreDocument", () => {
 
       expect(mock2.mock.calls.length).toBe(2);
     });
+
+    test("it should propagate the error when not subscribing", async () => {
+      const hookId = genId();
+      const id = genId();
+      const ref = doc(firestore, "noread", id);
+      const { result, waitFor } = renderHook(
+        () =>
+          useFirestoreDocument(hookId, ref, {
+            subscribe: false,
+          }),
+        {
+          wrapper,
+        }
+      );
+      await waitFor(() => result.current.isError, { timeout: 5000 });
+    });
+    test("it should propagate the error when subscribing", async () => {
+      const hookId = genId();
+      const id = genId();
+      const ref = doc(firestore, "noread", id);
+      const { result, waitFor } = renderHook(
+        () =>
+          useFirestoreDocument(hookId, ref, {
+            subscribe: true,
+          }),
+        {
+          wrapper,
+        }
+      );
+      await waitFor(() => result.current.isError, { timeout: 5000 });
+    });
   });
 
   describe("useFirestoreDocumentData", () => {

packages/utils/src/useSubscription.ts

@@ -51,7 +51,7 @@ type UseSubscriptionOptions<TData, TError, R> = UseQueryOptions<
  * Utility hook to subscribe to events, given a function that returns an observer callback.
  * @param queryKey The react-query queryKey
  * @param subscriptionKey A hashable key to store the subscription
- * @param subscribeFn Returns an unsubscribe function to the event, the argument of subscribeFn is a callback to set data.
+ * @param subscribeFn Returns an unsubscribe function to the event
  * @param options
  * @returns
  */
@@ -89,10 +89,11 @@ export function useSubscription<TData, TError, R = TData>(
   }, []);
 
   let resolvePromise: (data: TData | null) => void = () => null;
-
+  let rejectPromise: (err: any) => void = () => null;
   const result: CancellablePromise<TData | null> = new Promise<TData | null>(
-    (resolve) => {
+    (resolve, reject) => {
       resolvePromise = resolve;
+      rejectPromise = reject;
     }
   );
 
@@ -121,9 +122,9 @@ export function useSubscription<TData, TError, R = TData>(
     }
   } else {
     if (!options.fetchFn) {
-      throw new Error("please specify fetchFn");
+      throw new Error("You must specify fetchFn if using onlyOnce mode.");
     } else {
-      options.fetchFn().then((res: TData) => resolvePromise(res));
+      options.fetchFn().then(resolvePromise).catch(rejectPromise);
     }
   }