31 lines
698 B
TypeScript
31 lines
698 B
TypeScript
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// #docregion
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import { Pipe, PipeTransform } from '@angular/core';
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import { Http } from '@angular/http';
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import 'rxjs/add/operator/map';
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// #docregion pipe-metadata
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@Pipe({
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name: 'fetch',
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pure: false
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})
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// #enddocregion pipe-metadata
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export class FetchJsonPipe implements PipeTransform {
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private cachedData: any = null;
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private cachedUrl = '';
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constructor(private http: Http) { }
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transform(url: string): any {
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if (url !== this.cachedUrl) {
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this.cachedData = null;
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this.cachedUrl = url;
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this.http.get(url)
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.map( result => result.json() )
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.subscribe( result => this.cachedData = result );
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}
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return this.cachedData;
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}
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}
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