我正在做一个 POC 来证明我在 Angular Universal 的后端和前端之间进行了通信。我在后端有一个名为 heros.json 的 JSON 文件，我想ModelService从model.service.ts.
我有这个文件夹结构：
在model.service.ts（前端）内，我想创建一个 http 请求以在名为getStuff().
我在model.service.ts中有这个：
// domain/feature service
@Injectable()
export class ModelService {
private heroesUrl = "http://localhost:4000/src/backend/heroes.json"; // URL to JSON file
// This is only one example of one Model depending on your domain
constructor(public api: ApiService, public cacheService: CacheService, private http: Http) {
}
public getStuff(): Observable<any[]> {
return this.http.get(this.heroesUrl)
.map(this.extractData)
.catch(this.handleError);
}
private extractData(res: Response) {
let body = res.json();
return body.data || { };
}
private handleError (error: Response | any) {
// In a real world app, we might use a remote logging infrastructure
let errMsg: string;
if (error instanceof Response) {
const body = error.json() || "";
const err = body.error || JSON.stringify(body);
errMsg = `${error.status} - ${error.statusText || ""} ${err}`;
} else {
errMsg = error.message ? error.message : error.toString();
}
console.error(errMsg);
return Observable.throw(errMsg);
}
// domain/feature service
@Injectable()
export class ModelService {
private heroesUrl = "http://localhost:4000/src/backend/heroes.json"; // URL to JSON file
// This is only one example of one Model depending on your domain
constructor(public api: ApiService, public cacheService: CacheService, private http: Http) {
}
public getStuff(): Observable<any[]> {
return this.http.get(this.heroesUrl)
.map(this.extractData)
.catch(this.handleError);
}
private extractData(res: Response) {
let body = res.json();
return body.data || { };
}
private handleError (error: Response | any) {
// In a real world app, we might use a remote logging infrastructure
let errMsg: string;
if (error instanceof Response) {
const body = error.json() || "";
const err = body.error || JSON.stringify(body);
errMsg = `${error.status} - ${error.statusText || ""} ${err}`;
} else {
errMsg = error.message ? error.message : error.toString();
}
console.error(errMsg);
return Observable.throw(errMsg);
}
我从前端组件调用 ModelService.getHeroes：
export class HomeComponent {
public data: any = {};
constructor(public modelService: ModelService) {
// we need the data synchronously for the client to set the server response
// we create another method so we have more control for testing
this.universalInit();
}
public universalInit() {
this.modelService.getStuff().subscribe((data) => {
this.data = data;
});
}
我收到此错误：
GET /src/backend/heroes.json 404 3.698 ms - 46
404 - {"status":404,"message":"No Content"}
EXCEPTION: 404 - {"status":404,"message":"No Content"}
/private/var/root/vepo/node_modules/rxjs/Subscriber.js:227
throw err;
^
404 - {"status":404,"message":"No Content"}
[nodemon] app crashed - waiting for file changes before starting...
所以我在服务中的网址private heroesUrl = "http://localhost:4000/src/backend/heroes.json"; // URL to JSON file是错误的。鉴于该文件夹结构，网址是什么？因为实际运行的项目，输出，在 dist 中：
所以我不知道该放什么ModelService.heroesUrl。应该有什么字符串值ModelService.heroesUrl？