StateMismatchError when using redis

[larsblumberg]

We just enabled Redis for our reflex instances and suddently we get this error:

reflex.utils.exceptions.StateMismatchError: Searched for state reflex___state____state.src___views___company_dialog____state but found State({'reflex___state____state.src___views___company_dialog___financials_grid_table____state': {'kpi_formula_keys_rx_state_': <coroutine object AsyncComputedVar.__get__.<locals>._awaitable_result at 0x7e9ffa78b970>, 'kpi_items_rx_state_': <coroutine object AsyncComputedVar.__get__.<locals>._awaitable_result at 0x7e9ffa7884f0>, 'years_rx_state_': MutableProxy([])}}).

Previously -- without Redis -- we wouldn't get that one.

How to best debug this?

PS: On Reflex v0.8.16

[ruhz3]

Overview

a20f0bf
I was also looking into the issue above. In conclusion, it’s a bug that occurs because the state_cls variable is being reused in the Redis interface class. Refer to the corresponding commit and apply the fix yourself, or wait for the latest version.

Reproduce

if there are references to another State and that referenced State ends up at the end of the array due to alphabetical ordering, an error will occur.

import reflex as rx


class AState(rx.State):
    opened: bool = False
    counter: int = 0

    @rx.event
    def toggle(self):
        self.opened = not self.opened
        self.counter += 1


class BState(rx.State):
    @rx.var
    async def greeting(self) -> str:
        state = await self.get_state(AState)
        return f'{state.opened}'

class CState(rx.State):
    @rx.var
    async def greeting(self) -> str:
        state = await self.get_state(AState)
        return f'{state.opened}'

class DState(rx.State):
    @rx.var
    async def greeting(self) -> str:
        state = await self.get_state(AState)
        return f'{state.opened}'

class EState(rx.State):
    @rx.var
    async def greeting(self) -> str:
        state = await self.get_state(AState)
        return f'{state.opened}'

class TestState(rx.State):
    @rx.event
    async def test_get_astate(self):
        a_state = await self.get_state(AState)
        print(a_state.opened)


def index() -> rx.Component:
    return rx.container(
        rx.vstack(
            rx.button(
                "Bug",
                on_click=TestState.test_get_astate,
                color_scheme="red",
            ),
            width="100%",
        ),
        padding="4",
    )


app = rx.App()
app.add_page(index)

Cause

The root cause is variable shadowing in the Redis-side module. As mentioned earlier, this has already been fixed in the current main branch.

state_cls = self.state.get_class_substate(state_path)  # Store requested state

for state_cls in required_state_classes:  # ← Variable shadowing!
    # Process states...

# After loop, state_cls = last item in required_state_classes
return flat_state_tree[state_cls.get_full_name()]  # ← Returns wrong state!