I have a design question on how to manage firebase auth & redux saga states with react-native-firebase.
Example use-case
Let's start from the scenario that I have an app that uses the idToken for a variety of use cases, some in the views using information from the claims, and some in redux actions to make api calls.
Using redux-saga, I would expect to implement these two cases like so:
// in selectors.js
const getIdToken = (state) => state.idTokenResult?.token
const getUserRole = (state) => state.idTokenResult?.claims.role
// in view.js
const role = useSelector(Selectors.getUserRole)
// in actions.js
const idToken = yield select(Selectors.getIdToken)
With this in mind I want to make sure the idTokenResult is available & up to date in my state. I can do this we a few actions and reducers, by calling a login method & then relying on the dispatched event onIdTokenChanged to update my state on login & tokenRefreshes. Something like the following:
// in actions.js
function* onLogin(email, password){
yield call([auth(), 'signInWithEmailAndPassword'], email, password)
}
// This action would be called by an eventChannel which emits on each onIdTokenChanged
function* onIdTokenChanged(user){
yield put({ type: "UPDATE_USER", user: user, })
if (user){
const idTokenResut = yield call([auth().currentUser, 'getIdTokenResult'])
yield put({ type: "UPDATE_ID_TOKEN_RESULT", idTokenResult: idTokenResult, })
}
}
// in reducers.js
const reducer = (state = {}, action) => {
switch (action.type) {
case 'UPDATE_USER':
return { ...state, user: action.user };
case 'UPDATE_ID_TOKEN_RESULT':
return { ...state, idTokenResult: action.idTokenResult }
}
}
Problem
Here is when we run into a problem. I recently learned that the onIdTokenChanged is dispatched lazily, only when the getIdTokenResult() method is invoked link. This means that with the code above we cannot expect our state to be accurate, because when we call yield select(Selectors.getIdToken) it doesn't check getIdTokenResult() and therefore the onIdTokenChanged event is never dispatched.
Potential solutions
How do we overcome this problem?
Set up a timer which periodically calls getIdTokenResult() before the token expires, to trigger the event.
Should work, but defeats the purpose of having an onIdTokenChanged event. Also this means it will refresh the token hourly, even if it isn't needed or being accessed
Somehow call getIdTokenResult() in the selector?
It's an async method so it seems like an anti-pattern here and I'm not even sure it's possible
Use the library directly to fetch user states with auth().currentUser, and forget redux-saga
We lose the nice rerender functionalities that redux's useSelector provides. By accessing the state directly we'll need to figure out another way to trigger rerenders on auth changes, which defeats the purpose of using redux-saga
Something I didn't consider/implemented incorrectly?
Your suggestions are welcome and thanks in advance for you help! :)
Related
I'm wondering if it's possible to essentially "reevaluate" the middleware conditions without actually changing the current route.
The middleware's purpose is to prevent non-logged-in users from accessing the "dashboard".
My issue is, a user could become logged in or logged out without necessarily changing route but they wouldn't be redirected until they try and change pages.
I have a VueX action that triggers when the user's auth state changes but this (from what I can see), can't access the redirect or route variables.
// /mixins/auth.js
const reevaluateAuthStatus = (store, redirect, route) => {
console.log(route)
const redirectPolicy = route.meta.map((meta) => {
if (meta.auth && typeof meta.auth.redirectPolicy !== 'undefined') { return meta.auth.redirectPolicy[0] }
return []
})
const user = store.getters['auth/getUser']
if (redirectPolicy.includes('LOGGEDOUT')) {
if (user) {
return redirect('/dashboard')
}
} else if (redirectPolicy.includes('LOGGEDIN')) {
if (!user) {
return redirect('/login')
}
}
}
module.exports = {
reevaluateAuthStatus
}
// /middleware/auth.js
import { reevaluateAuthStatus } from '../mixins/auth'
export default function ({ store, redirect, route }) {
reevaluateAuthStatus(store, redirect, route)
}
Appreciate any help on this :)
You cannot re-evaluate a middleware AFAIK because it's mainly this (as stated in the documentation)
middlewares will be called [...] on the client-side when navigating to further routes
2 clean ways you can still achieve this IMO:
use some websockets, either with socket.io or something similar like Apollo Subscriptions, to have your UI taking into account the new changes
export your middleware logic to some kind of call, that you could trigger again by calling the $fetch hook again or any other data-related fetching hook in Nuxt
Some more ugly solutions would probably be:
making an internal setInterval and check if the actual state is still valid every 5s or so
move to the same page you are actually on with something like this.$router.go(0) as somehow explained in the Vue router documentation
Still, most of the cases I don't think that this one may be a big issue if the user is logged out, because he will just be redirected once he tries something.
As if the user becomes logged-in, I'm not even sure on which case this one can happen if he is not doing something pro-active on your SPA.
I don't know if it's relevant or not, but I solved a similar problem this way:
I have a global middleware to check the auth status. It's a function that receives Context as a parameter.
I have a plugin that injects itself into context (e.g. $middleware).
The middleware function is imported here.
In this plugin I define a method that calls this middleware passing the context (since the Plugin has Context as parameter as well): ctx.$middleware.triggerMiddleware = () => middleware(ctx);
Now the middleware triggers on every route change as intended, but I can also call this.$middleware.triggerMiddleware() everywhere I want.
Hi I am working on React Native app. I am using Redux and Saga. I call the API in componentDidMount.
async componentDidMount() {
let data = this.props.navigation.getParam("returnProductData");
if (data) {
console.log("Return Here");
this.props.getProductReturnAction(data)
this.setState({
returnQty:parseInt(this.props.product.item_ordered)-parseInt(this.props.product.already_return_qty)
});
console.log(this.state.returnQty,"Return quty"); //coming undefined
console.log(this.props.product, "product"); // undefined
console.log(this.props.product.item_ordered); //undefined
}
}
I have to set the state in componentDidMount for returnQty. But, state is not accessible here. It's working fine in render method. I can use all the product object. But, it is coming empty in componentDidMount. I tried using async and await but it's not working.
// Dispatch Methods
const mapDispatchToProps = dispatch => {
return bindActionCreators(
{ getProductReturnAction, submitProductReturnAction },
dispatch
);
};
// Props
const mapStateToProps = state => {
return {
product: state.myOrdersReducer.returnProduct
};
};
I can't be able to find out the bug please help to find out the best solution.
When you are making API calls through redux/saga, you can not use async await, as the frameworks will just dispatch an action and return back, the listeners which are registered for the action will be triggered and then after they complete their work they will dispatch a new action and respect reducer will handle the response.
Explained above is general scenario.
In your scenario,
You are dispatching the action returned by getProductReturnAction which will give say GET_PRODUCTS action.
A saga would be registered for GET_PRODUCTS, say getProducts, this get invoked.
This will perform the API call once the response is received it will dispatch GET_PRODUCTS_SUCCESS along with the products data.
Corresponding reducer which handles GET_PRODUCTS_SUCCESS will get called and that updates returnProduct and as you are registered for that in your component the render method gets called (as the props are changed) and hence product data is available in your render method.
This is working perfectly correct. I don't see anything wrong here.
As the data is available in props use the same u do not need to do a setState again on that.
I have a react app which will record audio.
When the user presses a button the component should cause it's parent to run a stopRecording() routine, resulting in saving the file and some json data about conditions and triggering a user flow.
I'd been looking into Redux which seems fine for JSON data but I'm less sure about audio files.
But does Redux fulfill the purpose of pub/sub for notifying components they should do stuff.
But does Redux fulfill the purpose of pub/sub for notifying components
they should do stuff.
Yes. Whenever the store changes, all "connected" components will receive the new store update and consequently componentDidUpdate will get called. So for example, let's say that you would like to trigger an action and listen on that trigger, then you would do something like this:
The subscriber
class MyListenerComponent extends Component {
...
componentDidUpdate(prevProps) {
if(this.props.triggerAction !== prevProps.triggerAction) {
// do something meaningful here, perform user flow, stop recording, whatever
}
}
...
}
const mapStateToProps = (state) => {
return({
triggerAction: state.triggerAction
})
}
export default connect(mapStateToProps)(MyListenerComponent)
The action triggerer (publisher)
this.props.dispatch({type: 'TRIGGER_ACTION', triggerAction: 'some data here'})
The reducer:
switch(action.type) {
case 'TRIGGER_ACTION':
return ({
...state,
triggerAction: action.triggerAction,
})
}
I'm pretty new to Vuex and am having difficulty understanding how to handle a state change from one module to another. Currently, I have a module called transactions which does an Ajax request and if successful it should close the Modal that is open. I have my modal state set in a separate module called General. I originally tried to set the General State of modal but committing my general mutation closeModal. I realized this won't work and as it sounds like Mutations aren't supposed to do this sort of heavy lifting. I've searched for another method to handle this sort of work and have been lead to Actions but I'm not clear on how to implement it or if it is even supposed to do this kind of work. Would someone please let me know if an Action is the correct method for this problem or if there is another way I should be addressing things.
I have a module called transactions that is running an ajax request and should close a modal if successful. For the sake of this issue, I've simplified my module.
const Transactions = {
state: {
},
mutations: {
CONFIRM_TRANSACTION_CANCEL: function(state) {
this.$store.commit('CLOSE_MODAL')
}
}
And I also have a second module called general which I want to use for general state management and error handling. I'm attempting to call a mutation from transactions into this general module.
const General = {
state: {
modalState: null,
},
mutations: {
...
CLOSE_MODAL: function(state) {
state.modalState = null
},
...
}
}
You should not make a commit inside a mutation. Mutations are only to change the state.
You could do this in two ways:
1.- Using Vue's Watch spying transaction state. Then, if the transaction is correctly done, you dispatch an action to close the Modal.
2.- You can dispatch an action to close the modal inside the action that launches the ajax call (after the success).
apiCall({ dispatch, commit }) {
api.get('/transaction')
.then((response) => {
dispatch('closeModal');
commit('TRANSACTION_SUCCESS', response);
})
.catch((error) => commit('TRANSACTION_ERROR', error));
}
These methods below are done with thinking of the modal as it should use vuex too but, if you want to simplify you can just:
3.- Pass the status of the transaction that comes from vuex directly to the modal by prop and handle the modal with it.
I'm using react-native-background-fetch to receive app refresh events and have been struggling to dispatch an action (that fetches data) when it's triggered. I'm able to do this outside of redux but not when I dispatch the action.
BackgroundFetch.configure({
stopOnTerminate: false
}, async () => {
await store.dispatch(getItemsAction);
BackgroundFetch.finish();
});
Action:
export function getItemsAction() {
// <-- Reaches here
return async (dispatch, getState) => {
// <-- But not here
const items = await findAll();
dispatch(itemsRetrieved(items));
}
}
If not a solution, I'd like to get some insight into what's happening here.
First of all you need to call action creator
await store.dispatch(getItemsAction());
Then you'll need a middleware to handle functions as actions. I assume you are aware of redux-thunk.
If it's a headless task running in the background, It does not have access to the redux store from what I experienced.
You will want to use something like AsyncStorage (https://github.com/react-native-community/async-storage) when running the task as headless js, which is what happens when the app is running background events.