I have a use case for synchronous storage for my react native app.
Before app renders a home view, I want to check if there is a session token stored on the local storage and proceed if it is available, otherwise want to render login component instead as the initial view.
Using sync storage will simplify the code.
I don't think there is a simple synchronous storage option. According to this answer localstorage is not implemented in the core IOS javascript engine. AFAIK the other options such as those used in this localstorage polyfill don't work. That leaves us with needing a react native module which are asynchonous by design. From the docs:
React Native bridge is asynchronous, so the only way to pass a result to JavaScript is by using callbacks or emitting events
So I think Async is the way to go.
For those who are searching for this,
I found this npm package that served this need
react-native-sync-localstorage
I have a similar situation and found Realm supports synchronous read, which is what I need. Realm is a bit big for single token storage. I use AsyncStorage for everything else. Let me know if you find a simpler solution.
There's no solution similar with Native Mobile development such as SharedPreferences in Android.
Native Way: most of the operations are synced. (such as read from storage, etc), some of the operations are async.(http request, load image)
React Native way: almost all of the operations are asynced. this is explained by #Ryan Harmuth 's answer.
So, let's start to use Redux as a solution. :)
Related
As the question suggests, I'm trying to figure out how to persist cached data beyond a phone reboot or app closure using React Native with Redux Toolkit Query. I've noticed that the cached data gets wiped in those scenarios. I believe that caching data beyond an app closure or phone reboot is a common practice.
I have thought about simply storing the data in client-side Redux using Redux Persist to get around this issue, without persisting the api slice. As this post indicates, persisting the api slice is a bad idea:
What happens when i use RTK Query with redux-persist?.
Any tips on this would be appreciated! Thank you.
Generally I can only repeat what I already said in the other issue:
I do not recommend doing this. Data from a server should be fresh, and this way it defitely won't be.
That said, we are currently working on SSR integration and that, too, will need similar functionality. So some kind of rehydration mechanism will be integrated, probably in Redux Toolkit 1.7 - but until then you have the choice between not keeping api data cached (again, my recommendation. No user wants to open an app and see data from five weeks ago - rather show them a loading screen!) or restoring it, but potentially ruining cache collection of said data.
I basically made a login page which could grab user/password from the text input, but if I want to use these to get auth from my website which has a REST API, where should I start it, is any lib that I can use?
I don't know how deeply you want to make. So I'll guess your concerning.
If you want to just send and get response from server
You can use fetch() method in js. Luckily react-native have documentation. https://reactnative.dev/docs/network Look this documents. React-Native have own fetch method for communicating with server.
If you want to manage state of your client-side data
Redux : You might probably hear this one. you can include redux in your package. we can use redux in react-natvie not only react. I just googled articles. https://www.digitalocean.com/community/tutorials/react-react-native-redux
MobX : Redux is pretty much complicate way to deal with state. So If you need simple things. you can try MobX. try this one. (also googled) https://www.smashingmagazine.com/2020/08/mobx-state-manager-react-native-applications/
Hope this idea helps you.
Best regards.
I am building a React Native app which requires calling AsyncStorage multiple times in different components.
For example a particular screen can only be opened in web if the user is logged in, which requires checking the local storage.
Callings AsyncStorage every time doesn’t seem like a good idea and might impact performance as the application grows.
Is implementing redux the best option or is there any other way?
Yes, if you rely on saving too many records. You can however optimize it by using redux persist or using in-memory cache.
A good read that helped understand optimization and performance of Async: https://medium.com/#Sendbird/extreme-optimization-of-asyncstorage-in-react-native-b2a1e0107b34
I have been using Firebase Web SDK for my react-native app (I am using FIRESTORE to store the data). Up to this point, I have had no problems. It all works smoothly. But now I want to add some kind of offline storage mechanism to my app so that I could still offer some functionality or display some content that was cached from the last connected session even if my users are offline. After some investigation, I have the impression that react-native-firebase is the preferred way to go. Now I have some questions and I like to get some advice from the experienced.
Is react-native-firebase the only option to go? I have quickly read about AsyncStorage and it is just a key-value storage. Considering the simplest thing I want to do is page through a list of firestore documents, this kind of storage seems not to be suitable to do this offline. Like If I wanted to do this with AsyncStorage I would have to put all the content (maybe hundreds of documents) I get from the firestore backend, persist them as a single string value, fetch them back, parse them, page them etc. And write custom logic& methods for all these.
If I was to use react-native-firebase, just enabling the offline storage -I assume- takes care of this for you and you don't have to write any custom logic for offline storage usage. I assume the data that has persisted for offline usage has the same structure as it does in firestore database. I feel like If I use anything other than react-native-firebase, I would have to handle all the custom logic for persisting, reading and rendering the data offline myself. Is that right?
The biggest concern I have is the amount of code refactoring that might be required. I have many lines of code and so many .get().then() like lines where I get and render the data from firestore. In the documentation of react-native-firebase it says:
...aims to mirror the official Firebase Web SDK as closely as
possible.
I am not sure to what extent this is true. I have checked the react-native-firebase's firestore module's reference documentation but I just can't tell how many of these querying methods are actually supported.
So, the way to go is react-native-firebase's way? Would it take a heavy toll on me trying to refactor the existing code? Any similar experience do you have?
I would appreciate any help.
Thanks a lot...
Maintainer of the react-native-firebase library here.
...aims to mirror the official Firebase Web SDK as closely as possible.
This is a minor disclaimer as there are some differences between the two, mainly down to how certain things have to be implemented with React Native.
For example, enablePersistence does not exist on RNFB. Instead, persistence is enabled by default and can be toggled off (or on) via settings().
Is react-native-firebase the only option to go? I have quickly read about AsyncStorage and it is just a key-value storage. Considering the simplest thing I want to do is page through a list of firestore documents, this kind of storage seems not to be suitable to do this offline. Like If I wanted to do this with AsyncStorage I would have to put all the content (maybe hundreds of documents) I get from the firestore backend, persist them as a single string value, fetch them back, parse them, page them etc. And write custom logic& methods for all these.
This is technically possible, however there are downsides to this as you have mentioned. With Firestore, when the device goes offline (quite common on apps) and you attempt a read/write it'll read/update your local cache, which will still trigger event listeners. When the app goes back online, it'll automatically re-sync with the server for you.
If I was to use react-native-firebase, just enabling the offline storage -I assume- takes care of this for you and you don't have to write any custom logic for offline storage usage. I assume the data that has persisted for offline usage has the same structure as it does in firestore database. I feel like If I use anything other than react-native-firebase, I would have to handle all the custom logic for persisting, reading and rendering the data offline myself. Is that right?
This is all handled for you. We wrap around the native Firebase SDKs so expect the same level of consistency if you were developing a native Android/iOS app if not using React Native.
The biggest concern I have is the amount of code refactoring that might be required. I have many lines of code and so many .get().then() like lines where I get and render the data from firestore.
Generally everything is the same apart from a few minor methods for reasons mentioned above.
So, the way to go is react-native-firebase's way? Would it take a heavy toll on me trying to refactor the existing code? Any similar experience do you have? I would appreciate any help.
I'd recommend anyone developing with React Native & Firebase to use RNFB. It provides a lot of extra functionality the Web SDK cannot provide with React Native. Apart from a more cumbersome setup & changing imports, it should work very much the same.
I have a react native mobile application and I need some pages to work offline (without internet connection) I am using redux persist library.
My question is where to initialize the store and persist it?
Should I make it for each page or one time?
You use it to persist either your entire redux store, or a part of the store. If your not using redux yet then you will need to implement that first.
It’s setup at the same time you create your redux store.
There are links to several examples and a guide start guide in the GitHub project readme.