Auto saving form without save button - Apollo, React - reactjs

I'm building React app with Apollo.
I would like to make a form like...
call mutation onChange of input
the value of input is changed as the user type
I tried...
useMutation to save the value
useQuery for the value of input
But the value is changed after saved. It's a little late. Also, I have to press delete key twice to make the value empty.
I know that I can use useState for the form value, but is there any way to do this easier? Is there any way to hold the form value even under unstable network, and try resending later?

'optimisticResponse' is the option for this case.
It's often possible to predict the most likely result of a mutation before your GraphQL server returns it. Apollo Client can use this "most likely result" to update your UI optimistically, making your app feel more responsive to the user.
https://www.apollographql.com/docs/react/performance/optimistic-ui/

Related

Efficient Firebase document reading and querying with hooks

I am currently using queries to get the initial state of a user. They potentially could have thousands of individual documents that don't need to be set up via hooks.
My current approach is mostly working, however it does mean there is a double read on the documents that I create the hook on.
query(
collection(firestore, "userDocs"),
where("ownedBy", "==", userId),
orderBy(documentId()),
limit(6)
)
This is my initial query, I am using react infinite scrolling to then fetch more as they scroll down. Each of these documents is a rendered component in React.
Within that component I then setup a hook to pretty much go and get the same data that I just did.
setCol(doc(firestore, "userDocs", userDocId),{
snapshotListenOptions: { includeMetadataChanges: true },
})
They both set a document state on the component, once on load, and when ever the firebase hook goes off. I am using a react firebase package here for hook simplification.
My question is, how can I get this hook functionality which I really need, but stop this initial read from the firebase hook. If I don't do the initial query for the documents, I don't get the data I need to make the hooks. And also an approach I tried of just using hooks passed to the user doc component was much slower than my query based approach because firebase queries are really fast than singular document reads.
I am basically trying to prevent a second read when the hook on the document is created because its data will just be the data I got back from the query and isn't very efficient. I have seen some implementations that get around this using a timestamp updated at field, but does that require me to perform an extra write on the documents that I've just queried?
When I update the document that triggers the hook its possible I can pop a timestamp field in then but Im not sure how that solves my initial read problem.
Many thanks for any suggestions :)

Use cases for when not to use redux?

I was always wondering if I should use redux store all the time even when it's not really necessary.
For example:
I have form with select field that has some options I fetch from API. Let's imagine that form is for adding new car listing and select options are car models. Should I directly call API from component and display options or should I create store CarModels or something like that and store results from API there and then map those values to state in component?
I have "Favorites" feature, when you click heart next to some item (let's say a car), do I need to go through dispatching all events FAVORITE_CAR_REQUEST, FAVORITE_CAR_SUCCESS etc... or is it good enough to just call API directly from component (using some kind of api-service of course).
It's related to question above. If I have screen where I show favorites, I should then probably have store and connect everything with actual favorite action so I update the list. On new favorite, API will return favorited item, should I push that one in list of favorites already in store or should I just load again latest list when user opens up the favorites screen?
Thanks in advance.
I think this is a perfectly valid question. What I feel like you're trying to ask is if you could/should mix react state and the redux store. The answer is sure! Just think about where you need to use that part of state before deciding where to store it. If you need a part of the state in multiple components, it probably makes sense to use Redux. If you only need state locally, perhaps to set form validation errors, maybe use react's state management if you feel like it. React and redux are both meant to be flexible, so as long as you're consistent in when you use the redux store and react state you should be good.
I found this article that also explains this pretty well: https://blog.jakoblind.no/is-using-a-mix-of-redux-state-and-react-local-component-state-ok/
I tend to use redux when the state has to be accessed globally / complex logic that i want to be logged properly

Initialize state from props using rehydrated Redux store

In my application I have a dialog window on which there are multiple input fields. What I want to do is to save user's input in the component's own state and only afterwards, say, inside "onClose" of the Dialog send the input to a redux store using "dispatch" function.
This way the dialog component would keep field data inside its own state.
The problem that I face is that I'm not sure what the best way is to rebuild dialog component state from information contained in the redux store.
If one refreshes the page with F5 or simply reloads it, then components lose their state and fields will appear blank, regardless of the fact that rehydrated redux store still contains valid input information.
The question is then, what is the best way to set components state from props? Moreover, doesn't it seem like an antipattern? What are some common techniques for such task?
One possibility is to set field values directly to those contained in "props". This would, however, imply that every small change of the input fields will result in copying and modifying redux store, which is slow & inefficient.
Usually building a state from props complicates code a lot, you have to map props both in constructor and getDerivedStatesFromProps.
I prefer to write component functions which return value based on passed props.
As you mentioned it may impact perfomance, to fix it you can use memoize-one library.
For more details you can check the following answer

Update Redux store for every character entered in a input field?

I have a sequential data collection app built with React and Redux. Right now, I have internal state for each page which has a form and when user clicks "Submit" button, I am dispatching the data collected in the state and updating my Redux store. Should I be dispatching an action on every key entered(debouncing) or should I store it in a local state and update Redux store at once?
Will there be a performance issue if I dispatch action to Redux store on every keypress since it is not an asynchronous call.
Well, the answer is: it depends.
Some argue that we loose some of the advantages of using a central store (like Redux) if you also have an internal state in the components. Like, if all your application state is just the redux store, storing the store, or the sequence of actions that lead to that store, will give you a complete picture of what was happening before maybe an error occurs.
I believe that is excessive. It is completely fine to store little stuff in your component's internal state, but there should be a well defined line.
In case of a form, you'd have controlled input elements, and you'll want a mechanism to submit the form with an action. It'd be necessary to have the contents of the form in the redux store.
One way would be to have the contents in an internal state, and only put them into redux form after a little debounce. But that has some edge cases. What if the user submits the form in the little debounce time? The form in the store is incomplete. Is thinking about all the edge cases worth it?
I believe just having the form elements controlled from the redux form is the simplest solution. The performance issue one would imagine is not really an issue. This is also what redux-form does (you can look at how that is implemented for inspiration).

Managing field values with redux-form

Typically, when I've created a form in react/redux myself, I have managed the inputs as 'controlled components', meaning when an input box changes, it calls a function that updates a variable that is fed back into the input. Of course, for me, this is the crux of redux, it's the flow.
However with redux-form, it seems I have no ability to do this on each of the fields. Almost as if, the fields are controlled, but within redux-form's own world, as far as I'm concerned they're not controlled as I'm not passing a value and re-acting to a change with a callback.
This is causing me a problem, as I may have something else that updates those input fields. For example a postcode lookup might update an address's fields. Before I transitioned to redux-form, the 'flow binding' meant I could update those fields from a different reducer as they essentially just represented a live slice of the redux store.
How do I get around this?
Edit: I think the best approach might be to use this https://redux-form.com/7.0.3/examples/selectingFormValues/, but I'm not sure
Field values of redux forms can be modified using the reducer plugin. Basically you can add your own reducer to the one of redux form anf modify forms state like values, touched etc. Check it out here:
http://redux-form.com/7.0.3/docs/api/ReducerPlugin.md/
Be aware is an advanced usage of redux and redux forms.

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