2015-05-19 15:12:59 -07:00

50 lines
1.6 KiB
TypeScript

import {Injectable} from 'angular2/di';
import {isBlank, isPresent, BaseException, stringify} from 'angular2/src/facade/lang';
import {Map, MapWrapper, StringMapWrapper, StringMap} from 'angular2/src/facade/collection';
import {PromiseWrapper, Promise} from 'angular2/src/facade/async';
import {DOM} from 'angular2/src/dom/dom_adapter';
import {XHR} from 'angular2/src/services/xhr';
import {ViewDefinition} from '../../api';
import {UrlResolver} from 'angular2/src/services/url_resolver';
/**
* Strategy to load component templates.
* TODO: Make public API once we are more confident in this approach.
*/
@Injectable()
export class TemplateLoader {
_xhr: XHR;
_htmlCache: StringMap<string, /*element*/ any>;
constructor(xhr: XHR, urlResolver: UrlResolver) {
this._xhr = xhr;
this._htmlCache = StringMapWrapper.create();
}
load(template: ViewDefinition): Promise</*element*/ any> {
if (isPresent(template.template)) {
return PromiseWrapper.resolve(DOM.createTemplate(template.template));
}
var url = template.absUrl;
if (isPresent(url)) {
var promise = StringMapWrapper.get(this._htmlCache, url);
if (isBlank(promise)) {
promise = this._xhr.get(url).then(function(html) {
var template = DOM.createTemplate(html);
return template;
});
StringMapWrapper.set(this._htmlCache, url, promise);
}
// We need to clone the result as others might change it
// (e.g. the compiler).
return promise.then((tplElement) => DOM.clone(tplElement));
}
throw new BaseException('View should have either the url or template property set');
}
}