Option to trigger mutation on mount?

[aryzing]

Queries run on mount, yet mutations need to be explicitly invoked. Would it make sense to add a "mutate on mount" feature?

Usecase: having a page that always runs the same action (mutation) when the user navigates to it.

Right now handling it with

useEffect(() => {
  mutate(args);
}, [mutate, args]);

although would be great to have something like

useMutation({
  mutateOnMount: true,
  mutateFn: incrementServerCounter,
  mutationKey: ["inc", args],
});

[TkDodo]

having a page that always runs the same action (mutation) when the user navigates to it.

to do what exactly? mutations change some state, and changing some state depending on a UI rendering (which can happen often) is rarely a good idea.

it’s probably better to move that action to wherever the user initiates the navigation (link click, button click).

[aryzing]

Was reviewing existing uses, and realized that many are fundamentally queries to data available async'ly on the client, so may not need on-mount mutations after all. I believe these can (should) be switched to useQuery().

The one place where it may still be useful is when checking local storage on mount, applying any data migrations, and rendering the rest of the app when done. Although for this one case, can just keep the current useMutation + useEffect combo.

Thank you, appreciate that this discussion made me review the app and find a better solution.