Cross orgin error in google chrome for the api call

Question

in the nodejs backend i have added this code to the server.js

app.use(function(req, res, next) {
    res.header("Access-Control-Allow-Origin", "*");
    res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
    next();
});

but in angularjs 2 client side in google chrome is throwing this error

XMLHttpRequest cannot load http://localhost:8080/team. 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 405.

this is the service code for angular2 i'm using

export class DataService {
    // URL to web api

    constructor(private http: Http, private _configuration: Configuration,private team:Team) {

        //this.actionUrl = _configuration.ServerWithApiUrl;
        this.actionUrl = "http://localhost:8080/team";

    }
    private actionUrl: string;

    addData(postData: Team): Observable<Team[]> {

        //let body = JSON.stringify({ Team });
        this.team = postData;
        console.log(this.team);
        let body = JSON.stringify({ postData });
        let headers = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: headers });

        console.log(body);

        return this.http.post(this.actionUrl, body, options)
            .map(this.extractData)
            .catch(this.handleError);

    }

Answer 1

UPDATED:

For your new error message: Angular2 is lower-casing the headers. Please update your backend to accept content-type too.

res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, content-type, Accept");

You cant test post's to this URL: http://posttestserver.com/post.php?dir=anyNameYouWillFind

And can see your posts there: http://posttestserver.com/data/

Browse to year, month, day and anyNameYouWillFind ..

OLD:

you have to prefix your url!!

this.http.get(' http ://localhost:8080/v1_user/45646/team');

Answer 2

Fixed it by adding this to the backend node.js

// access control --> allowed all origin
app.use(function(req, res, next) {
    res.header("Access-Control-Allow-Origin", "*");
    res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
    // Request headers you wish to allow
    res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type');

    next();
})

.options('*', function(req, res, next){
    res.end();
})
;