Dispatch decorator

Reusable logic for avoiding Store injection

This package simplifies dispatching process, you shouldn't care about Store service injection as we provide more declarative way to dispatch events out of the box.

📦 Install

To install @ngxs-labs/dispatch-decorator run the following command:

npm install @ngxs-labs/dispatch-decorator --save

# or if you use yarn
yarn add @ngxs-labs/dispatch-decorator

🔨 Usage

Import the module into your root application module:

import { NgModule } from '@angular/core';
import { NgxsModule } from '@ngxs/store';
import { NgxsDispatchPluginModule } from '@ngxs-labs/dispatch-decorator';

@NgModule({
    imports: [
        NgxsModule.forRoot(states),
        NgxsDispatchPluginModule.forRoot()
    ]
})
export class AppModule {}

Dispatch

@Dispatch() is a function that allows you to decorate methods and properties of your components, basically arrow functions are properties. Firstly you have to create a state:

import { State, Action, StateContext } from '@ngxs/store';

export class Increment {
    public static readonly type = '[Counter] Increment';
}

export class Decrement {
    public static readonly type = '[Counter] Decrement';
}

@State<number>({
    name: 'counter',
    defaults: 0
})
export class CounterState {
    @Action(Increment)
    public increment({ setState, getState }: StateContext<number>) {
        setState(getState() + 1);
    }

    @Action(Decrement)
    public decrement({ setState, getState }: StateContext<number>) {
        setState(getState() - 1);
    }
}

Register this state in NgxsModule and import this state and actions in your component:

import { Component } from '@angular/core';
import { Select } from '@ngxs/store';
import { Dispatch } from '@ngxs-labs/dispatch-decorator';

import { Observable } from 'rxjs';

import { CounterState, Increment, Decrement } from './counter.state';

@Component({
    selector: 'app-root',
    template: `
        <ng-container *ngIf="counter$ | async as counter">
            <h1>{{ counter }}</h1>
        </ng-container>

        <button (click)="increment()">Increment</button>
        <button (click)="decrement()">Decrement</button>
    `
})
export class AppComponent {
    @Select(CounterState)
    public counter$: Observable<number>;

    @Dispatch()
    public increment = () => new Increment()

    @Dispatch()
    public decrement = () => new Decrement()
}

Also, your dispatchers can be asynchronous, they can return Promise or Observable, asynchronous operations are handled outside Angular's zone, thus it doesn't affect performance:

export class AppComponent {
    // `ApiService` is defined somewhere
    constructor(private api: ApiService) {}

    @Dispatch()
    public async setAppSchema(): Promise<SetAppSchema> {
        const { version, shouldUseGraphQL } = await this.api.getInformation();
        const { schema } = await this.api.getSchemaForVersion(version);
        return new SetAppSchema(schema);
    }

    // OR

    @Dispatch()
    public setAppInformation = () => this.api.getInformation().pipe(
        switchMap(({ version }) => this.api.getSchemaForVersion(version)),
        map(({ schema }) => new SetAppSchema(schema))
    );
}

Notice that it doesn't matter if you use an arrow function or a normal class method.

Dispatching multiple events

Your dispatchers can also return arrays with events inside:

export class AppComponent {
    @Dispatch()
    public setLanguageAndNavigateHome = (language: string) => {
        return [new SetLanguage(language), new Navigate('/')];
    }
}