graphql after running mutation if I quickly goback to Previous page, occur error - graphql

Question

after running mutation using the graphql, if I quickly goback to Previous page,
occur error : Warning: Can't perform a React state update on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and
asynchronous tasks in %s.%s, a useEffect cleanup function,
I think it's because I quickly go to another page during the mutation.
If this is not the case, there is no error.
(Even if an error occurs, update succeeds. but I'm worried about errors)
Even if move to another page during mutating, I want to proceed with the update as it is
How can I proceed with the update?
if If there is no way, is there method that How to create a delay during mutating
im so sorry. my english is not good.
const CalendarTodo = ({
month,
day,
data,`enter code here`
isImportWhether,
setIsImportWhether
}) => {
const [value, setValue] = useState("");
const monthDay = `${month + 1}월 ${day}일`;
const [createToDoMutation] = useMutation(CREATE_TODO, {
variables: {
toDoId:
data &&
data.toDos &&
data.toDos.filter(object => object.monthDay === monthDay)[0] &&
data.toDos.filter(object => object.monthDay === monthDay)[0].id,
monthDay: monthDay,
dayToDo: value,
importEvent: isImportWhether
},
update: (proxy, { data: { createToDo } }) => {
const data = proxy.readQuery({ query: SEE_TODO_OF_ME });
data &&
data.toDos &&
data.toDos.filter(object => object.monthDay === monthDay)[0] &&
data.toDos
.filter(object => object.monthDay === monthDay)[0]
.dayToDo.push(createToDo);
proxy.writeQuery({ query: SEE_TODO_OF_ME, data });
},
optimisticResponse: {
createToDo: {
__typename: "DayToDo",
id: Math.random().toString(),
toDoList: value,
importEvent: isImportWhether
}
}
});
return (
<>
);
};
export default CalendarTodo;

Answer 1

As you already guessed the reason is the asynchronous request that keeps on running even after un-mounting the component due to navigating away from it.
There are many ways to solve this. One is to add a check whether or not the component you are calling the async request from is still mounted and only update its state if so, e.g.:
useEffect(() => {
let isMounted = true;
apollo.mutate({query, variables, update: {
if(isMounted) {
// update state or something
}
})
return () => {
isMounted = false;
};
}, []);
This way however the data might be lost. If you want to make sure that you receive and store the return value you should add the request to a higher level component or context hat will not be unmounted on navigation. This way you can trigger the async call but dont have to worry about navigating away.