npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

ng-loadable-content

v2.0.6

Published

Loadable Content monad and angular pipes for using it

Downloads

125

Readme

ng-loadable-content

LoadableContent monad and angular pipes for using it.

Install

npm i ng-loadable-content

Usage

Let's assume we have some api endpoint, which returns an object. We have a service, which returns this object:

import {Observable} from 'rxjs/internal/Observable';

export interface Dto {
    id: number;
    name: string;
}

export interface RemoteService {
    
    loadObject(): Observable<Dto>;
    
}

First we import the module:

import {LoadableContentModule} from 'ng-loadable-content';

@NgModule({
    ...
    imports: [
        ...
        LoadableContentModule
    ]
})
export class AppModule {
}

We want the loader to be shown while we load that object. Usual use-case for this is to have a store:

import {Injectable} from '@angular/core';
import {BehaviorSubject} from 'rxjs';
import {LoadableContent} from 'ng-loadable-content';

@Injectable()
export class ObjectStore {

    private readonly _state = new BehaviorSubject<LoadableContent<Dto>>(LoadableContent.initial());
    readonly state$ = this._state.asObservable();

    constructor(private readonly remoteService: RemoteService) {
    }

    reload() {
        this._state.next(LoadableContent.loading());
        this.remoteService.loadObject()
            .subscribe(
                res => this._state.next(LoadableContent.loaded(res)),
                e => this._state.next(LoadableContent.error(e))
            );
    }

}

We use LoadableContent object to wrap the actual result. This object anytime can answer if the result is already loaded, is it being loading right now or was there any error while we tried to load it.

Next, we use this in a component:

import {Observable} from 'rxjs';
import {LoadableContent} from 'ng-loadable-content';

@Component({
    selector: 'app-object',
    templateUrl: './object.component.html',
    providers: [ObjectStore]

})
export class ObjectComponent {

    readonly state$: Observable<LoadableContent<Dto>>;

    constructor(private readonly objectStore: ObjectStore) {
        this.state$ = objectStore.state$;
        this.objectStore.reload();
    }

}

and the template.

<div>
    
    <ng-container *ngIf="state$ | async as state">
        <div *ngIf="state | loaded as dto">{{dto.name}}</div>
        <mat-progress-bar *ngIf="state | loading" mode="indeterminate"></mat-progress-bar>
        <div *ngIf="state | loadError">
            Failed to load dto
        </div>
    </ng-container>

</div>

We can use special pipes loading, loaded and loadError to select the required state.

We can also transform the result with map() method like this:

import {Observable} from 'rxjs';
import {LoadableContent} from 'ng-loadable-content';
import {map} from 'rxjs/internal/operators';

export class ObjectComponent {

    readonly state$: Observable<LoadableContent<string>>;

    constructor(private readonly objectStore: ObjectStore) {
        this.state$ = objectStore.state$.pipe(
            map(s => s.map(_ => _.name))
        );
        this.objectStore.reload();
    }

}

The loadable content can be transformed to loading and error state preserving its value. This can be useful when you want to show the loader above the content (e.g. table), but do not want the content to disappear.

import {Injectable} from '@angular/core';
import {BehaviorSubject} from 'rxjs';
import {LoadableContent} from 'ng-loadable-content';

@Injectable()
export class ObjectStore {

    private readonly _state = new BehaviorSubject<LoadableContent<Dto>>(LoadableContent.initial());
    readonly state$ = this._state.asObservable();

    constructor(private readonly remoteService: RemoteService) {
    }

    reload() {
        const current = this._state.value;
        this._state.next(current.toLoadingState);
        this.remoteService.loadObject()
            .subscribe(
                res => this._state.next(LoadableContent.loaded(res)),
                e => this._state.next(current.toErrorState(e))
            );
    }

}