javascript - Angular 2 访问 redmine Rest Api，无 'Access-Control-Allow-Origin'

Question

我尝试通过他们的 Rest Api 从 redmine 获取问题。当我从 postman 处调用它时，我得到响应，但是当我从我的 Angular 应用程序调用它时，我收到这样的错误

OPTIONS https://redmine.ourDomain.net/issues.json 404 (Not Found) XMLHttpRequest cannot load https://redmine.ourDomain.net/issues.json. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:3000' is therefore not allowed access. The response had HTTP status code 404.

这就是我在 Angular 中的做法

login(user: User): Observable<boolean> {
    var headers: Headers = new Headers();
    headers.append("Authorization", "Basic " + btoa(user.login + ":" + user.password));
    let options = new RequestOptions({ headers: headers });
    return this.http.get("https://redmine.ourDomain.net/issues.json", options)
        .map((response: Response) => {
            debugger;
            if (response.status == 200) {
                // set token property

                // store username and jwt token in local storage to keep user logged in between page refreshes
                localStorage.setItem('currentUser', JSON.stringify({ user }));

                // return true to indicate successful login
                return true;
            } else {
                // return false to indicate failed login
                return false;
            }
        });
}

请求在我的浏览器中看起来是这样的

Answer 1

您需要在后端启用 CORS 访问:http://www.redmine.org/plugins/redmine_cors

这是一个很好的扩展，可以让您在正常的 CORS 限制之外测试前端代码。它严格用于测试，对生产应用程序没有帮助，但很高兴拥有:https://chrome.google.com/webstore/detail/allow-control-allow-origi/nlfbmbojpeacfghkpbjhddihlkkiljbi