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Gate - a bridge between props and store

Imagine you have the task of transferring something from react props to the effector store. Suppose you pass the history object from the react-router to the store, or pass some callbacks from render-props. In a such situation Gate will help.

import {createStore, createEffect, forward} from 'effector'
import {useStore, createGate} from 'effector-react'

// Effect for api request
const getTodoFx = createEffect(async ({id}) => {
const req = await fetch(`https://jsonplaceholder.typicode.com/todos/${id}`)
return req.json()
})

// Our main store
const $todo = createStore(null).on(getTodoFx.doneData, (_, todo) => todo)

const TodoGate = createGate()

// We callgetTodoFx effect every time Gate updates its state.
forward({from: TodoGate.state, to: getTodoFx})

TodoGate.open.watch(() => {
//called each time when TodoGate is mounted
})
TodoGate.close.watch(() => {
//called each time when TodoGate is unmounted
})

function Todo() {
const todo = useStore($todo)
const loading = useStore(getTodoFx.pending)

if (loading) {
return <div>Loading...</div>
}

if (!todo || Object.keys(todo).length === 0) {
return <div>empty</div>
}

return (
<div>
<p>title: {todo.title}</p>
<p>id: {todo.id}</p>
</div>
)
}

const App = () => {
// value which need to be accessed outside from react
const [id, setId] = React.useState(0)

return (
<>
<button onClick={() => setId(id + 1)}>Get next Todo</button>
{/*In this situation, we have the ability to simultaneously
render a component and make a request, rather than wait for the component*/}
<TodoGate id={id} />
<Todo />
</>
)
}

ReactDOM.render(<App />, document.getElementById('root'))

Try it