feat(database): add converter option to useObjectValue hooks

README.md

@@ -129,6 +129,8 @@ const [objectValue, loading, error] = useObjectValue(query);
 Params:
 
 -   `query`: Realtime Database query
+-   `options`: Options to configure how the object is fetched
+    -   `converter`: Function to extract the desired data from the DataSnapshot. Similar to Firestore converters. Default: `snap.val()`.
 
 Returns:
 
@@ -147,6 +149,8 @@ const [objectValue, loading, error] = useObjectValueOnce(query);
 Params:
 
 -   `query`: Realtime Database query
+-   `options`: Options to configure how the object is fetched
+    -   `converter`: Function to extract the desired data from the DataSnapshot. Similar to Firestore converters. Default: `snap.val()`.
 
 Returns:
 

src/database/useObjectValue.ts

@@ -1,24 +1,37 @@
-import { onValue, Query } from "firebase/database";
+import { DataSnapshot, onValue, Query } from "firebase/database";
 import { useCallback } from "react";
 import { ValueHookResult } from "../common";
 import { useListen, UseListenOnChange } from "../internal/useListen";
 import { isQueryEqual } from "./internal";
 
 export type UseObjectValueResult<Value = unknown> = ValueHookResult<Value, Error>;
 
+export type UseObjectValueConverter<Value> = (snap: DataSnapshot) => Value;
+
+export interface UseObjectValueOptions<Value> {
+    converter?: UseObjectValueConverter<Value>;
+}
+
 /**
  * Returns and updates the DataSnapshot of the Realtime Database query
  *
  * @template {Value} Type of the object value
  * @param {Query | undefined | null} query Realtime Database query
+ * @param {?UseObjectValueOptions} options Options to configure how the object is fetched
+ * * `converter`: Function to extract the desired data from the DataSnapshot. Similar to Firestore converters. Default: `snap.val()`.
  * @returns {UseObjectValueResult} User, loading state, and error
  * * value: Object value; `undefined` if query is currently being fetched, or an error occurred
  * * loading: `true` while fetching the query; `false` if the query was fetched successfully or an error occurred
  * * error: `undefined` if no error occurred
  */
-export function useObjectValue<Value = unknown>(query: Query | undefined | null): UseObjectValueResult<Value> {
+export function useObjectValue<Value = unknown>(
+    query: Query | undefined | null,
+    options?: UseObjectValueOptions<Value>
+): UseObjectValueResult<Value> {
+    const { converter = (snap: DataSnapshot) => snap.val() } = options ?? {};
+
     const onChange: UseListenOnChange<Value, Error, Query> = useCallback(
-        (stableQuery, next, error) => onValue(stableQuery, (snap) => next(snap.val()), error),
+        (stableQuery, next, error) => onValue(stableQuery, (snap) => next(converter(snap)), error),
         []
     );
 

src/database/useObjectValueOnce.ts

@@ -1,25 +1,39 @@
-import { get, Query } from "firebase/database";
+import { DataSnapshot, get, Query } from "firebase/database";
 import { useCallback } from "react";
 import { ValueHookResult } from "../common";
 import { useOnce } from "../internal/useOnce";
 import { isQueryEqual } from "./internal";
 
 export type UseObjectValueOnceResult<Value = unknown> = ValueHookResult<Value, Error>;
 
+export type UseObjectValueOnceConverter<Value> = (snap: DataSnapshot) => Value;
+
+export interface UseObjectValueOnceOptions<Value> {
+    converter?: UseObjectValueOnceConverter<Value>;
+}
+
 /**
  * Returns the DataSnapshot of the Realtime Database query. Does not update the DataSnapshot once initially fetched
  *
  * @template {Value} Type of the object value
  * @param {Query | undefined | null} query Realtime Database query
+ * @param {?UseObjectValueOnceOptions} options Options to configure how the object is fetched
+ * * `converter`: Function to extract the desired data from the DataSnapshot. Similar to Firestore converters. Default: `snap.val()`.
  * @returns {UseObjectValueOnceResult} User, loading state, and error
  * * value: Object value; `undefined` if query is currently being fetched, or an error occurred
  * * loading: `true` while fetching the query; `false` if the query was fetched successfully or an error occurred
  * * error: `undefined` if no error occurred
  */
-export function useObjectValueOnce<Value = unknown>(query: Query | undefined | null): UseObjectValueOnceResult<Value> {
+export function useObjectValueOnce<Value = unknown>(
+    query: Query | undefined | null,
+    options?: UseObjectValueOnceOptions<Value>
+): UseObjectValueOnceResult<Value> {
+    const { converter = (snap: DataSnapshot) => snap.val() } = options ?? {};
+
     const getData = useCallback(async (stableQuery: Query) => {
         const snap = await get(stableQuery);
-        return snap.val();
+        return converter(snap);
     }, []);
+
     return useOnce(query ?? undefined, getData, isQueryEqual);
 }