Solution.js

//this code snippet solve the problem with frontend refresh when you write the cache with PostForm:

//in Home.js use this:
	const [posts, setPosts] = useState([]);
	const { user } = useContext(AuthContext);
	const { loading, data } = useQuery(FETCH_POSTS_QUERY);
	useEffect(() => {
		if (data) {
			setPosts(data.getPosts);
		}
	}, [data]);
  
  //and in PostForm.js use this:
  	const [createPost, { error }] = useMutation(CREATE_POST_MUTATION, {
		variables: values,
		update(proxy, result) {
			const data = proxy.readQuery({
				query: FETCH_POSTS_QUERY
			});
			const new_post = result.data.createPost;
			proxy.writeQuery({
				query: FETCH_POSTS_QUERY,
				data: { getPosts: [new_post, ...data.getPosts] }
			});
			values.body = '';
		}
	});
  
//this solution was not my idea, but one code hero help us :)

Thx

thank you!

Really Helpful. Thank you very much.
I was struggling with google to solve this and finally got the answer here.

Thank you!

to resolve the updating UI issue, try to add this inside your useMutation function
refetchQueries: refetchPosts => [{query: FETCH_POSTS_QUERY}]
hope it's helpful! ;)