为啥 Cors 阻止我对我的 Api 的请求？ [复制]

Posted 2023-03-03

【中文标题】为啥 Cors 阻止我对我的 Api 的请求？ [复制]

【英文标题】：Why is Cors blocking my request to my Api? [duplicate]为什么 Cors 阻止我对我的 Api 的请求？ [复制]

【发布时间】：2020-09-05 20:01:24

【问题描述】：

我正在开发一个项目，我需要访问我开发的 Api

const endpoint = 'localhost:3000/api/v1/';
const httpOptions = 
  headers: new HttpHeaders(
    'Content-Type': 'application/json',
  ),
;

@Injectable(
  providedIn: 'root',
)
export class RestService 
  constructor(private http: HttpClient) 

  private extractData(res: Response) 
    let body = res;
    return body || ;
  

  getRequest(id: String): Observable<Request> 
    return this.http.get<Request>(endpoint + 'request/' + id, httpOptions);
  

我已经授予权限以便我可以访问它，但我收到此错误

ccess to XMLHttpRequest at 'localhost:3000/api/v1/request/5ec3fbd84fe7bf4aa8d48b39' from origin 'http://localhost:4200' has been blocked by CORS policy: Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, https.

这里是权限：

app.use(
  cors(
    credentials: true,
    origin: "http://localhost:4200",
  )
);

找到了解决办法。端点应该是'http://localhost:3000/api/v1/'

【参考方案1】：

错误消息提到请求的无效方案。尝试将“http”添加到您的端点

const endpoint = 'http://localhost:3000/api/v1/';