[database] Add useObjectVal hook

Author: chrisbianca

database/index.js.flow

@@ -7,7 +7,7 @@ export type ListHook = {
   value: DataSnapshot[];
 };
 export type ObjectHook = {
-  error?: object;
+  error?: Object;
   loading: boolean;
   value?: DataSnapshot;
 };

database/index.ts

@@ -1,2 +1,3 @@
 export { default as useList, ListHook } from './useList';
 export { default as useObject, ObjectHook } from './useObject';
+export { default as useObjectVal, ObjectValHook } from './useObjectVal';

database/useObjectVal.ts

@@ -0,0 +1,17 @@
+import { database } from 'firebase';
+import useObject from './useObject';
+
+export type ObjectValHook<T> = {
+  error?: object;
+  loading: boolean;
+  value?: T;
+};
+
+export default <T>(query: database.Query): ObjectValHook<T> => {
+  const { error, loading, value } = useObject(query);
+  return {
+    error,
+    loading,
+    value: value ? value.val() : undefined,
+  };
+};

firestore/index.js.flow

@@ -8,12 +8,12 @@ import type {
 } from 'firebase/firestore';
 
 export type CollectionHook = {
-  error?: object;
+  error?: Object;
   loading: boolean;
   value?: firestore.QuerySnapshot;
 };
 export type DocumentHook = {
-  error?: object;
+  error?: Object;
   loading: boolean;
   value?: firestore.DocumentSnapshot;
 };

storage/index.js.flow

@@ -2,7 +2,7 @@
 import type { Reference } from 'firebase/storage';
 
 export type DownloadURLHook = {
-  error?: object;
+  error?: Object;
   loading: boolean;
   value?: string;
 };