rx-firebase-store

A simple reactive store for state management using RxJs. Can be used in React but will also work with other frameworks.

Created to seperate state management from the UI components without a lot of boilerplate code.

Inspired by this blog and the names of the events are inspired by ngxs

Examples

Here a demo and the code

init

firebase needs to to initialized.

 initFirebase(enviroment.firebase, 'europe-west1', { collectionName: 'actions' }) => {

To log all actions to firebase use the logOptions.

create

// creates a new store
const store = createStore<ActivityStateModel>(initialState, !environment.production);

In reactJs the store can be mapped to the component state like this:

export function MyComponent() {
  const [state, setState] = useState(store.currentState());

  useEffect(() => {
    const subs = store.subscribe(setState);
    store.dispatch(new LoadAction());
    return subs.unsubscribe;
  }, []);

actions

Create an action that implements StoreAction<T, M>

export class LoadAction implements StoreAction<StateModel, never> {
    type = "LOAD";
    async execute(ctx: StateContext<StateModel>): Promise<StateModel> {
        if (ctx.getState().users.length === 0) {
            ctx.patchState({ loading: true });
            const users = (await axios.get<ApiResponse>('https://randomuser.me/api/?results=20')).data.results;
            return ctx.patchState({ loading: false, users });
        }
    }
}

API

Store:

• constructor: (initialState: T = The initial state, devTools: boolean = connect to redux devTools)
• callback: (action: StoreAction<T, unknown>, oldState: T, newState: T, storeContext: Map<string, unknown>) => void can be used capture all actions. For example to log all actions to the console or database.
• dispatch: (action: StoreAction<T, unknown>) => Promise: dispatches an action and return a promise with the new state
• currentState: returns the current state.
• asObservable: return an observable of T

ctx: StateContext

• getContext(name: string): gets the context that is added while creating the store. E.g. use to access History *
• dispatch: (action: StoreAction<T, unknown>) => Promise: dispatches an action and return a promise with the new state
• getState: gets the current state.
• setState: set the entire new state.
• patchState: set only the changed properties of the state, these will be merged with the current state.
• auth, firestore, functions and storage to get firebase functions

• To use getContext() you have to set the dependency somewhere where it is available:

  setStoreContext([
    { name: 'history', dependency: useHistory() }
  ])

In the action you can use:

  const history = ctx.getContext<History>('history');