Is there some sort of extra reducers for rtk query endpoint?

[MaximKondratev]

There is a way to use extraReducers of a slice to do something with slice state depending on rtk query actions like matchFulfilled (example from the docs)

Is there a way to do similar things for a query itself? I have two queries and when one fulfills I want to fill (upsert or update) second query with data from first query.

Right now I am able to do it this way:

firstQuery: builder.query({
    query: ...,
    onQueryStarted: async (arg, queryLifecycleApi) => {
        const result = await queryLifecycleApi.queryFulfilled;
    
        dispatch(upsertSecondQuery(result));
    }
}

But I want to do it the other way. I want to subscribe secondQuery to match firstQuery fulfill and change state with result:

secondQuery: builder.query({
    query: ...,
    extraReducers: (builder) => {
        builder.addMatcher(api.endpoints.firstQuery.matchFulfilled, (state, firstQueryFulfillAction) => {
            // somehow upsert data like in usual slice
        })
    }
}

I'm pretty sure it's impossible but maybe I just can't find it in the docs

[EskiMojo14]

onQueryStarted is the right place for this. You can't add more reducers to the RTK Query slice after it's created. If you wanted to respond to some other action (not something covered by queryFulfilled) you could use a listener:

startListening({
  actionCreator: hydrateMyQuery,
  effect: (action, { dispatch }) => dispatch(myApi.endpoints.myQuery.upsertQueryData(action.payload))
})

but that seems like a rare case.

[MaximKondratev]

I wanted to inverse dependency as firstQuery is more like a top-level feature and secondQuery should be aware about it and not the other way (at least in my thoughts). Same like some slices can be aware of firstQuery through extraReducers with queryFulfilled action while firstQuery doesn't know about these slices directly.

While listener middleware can be treated as some sort of inversion in my case, it still requires setup outside of a secondQuery definition, so I don't think there is much difference.

Thanks for fast answer!