设置自定义内容类型xmlhttprequest

Question

I have an API I am trying to interface with that requires a custom content-type header be set, with the value text/xmlmc

I've implemented this like so

    Xmlmc.prototype.submitRequest = function (request,callback) {
    var self = this;
    var port = portMap[request.service] || 5015;
    var endpoint = this.endpoint = 'http://' + this.server + ':' + port;
    var xml = request.toXml();
    var xhttp;
    if (window.XMLHttpRequest) {
        xhttp = new XMLHttpRequest();
    } else {
        // IE 5 and 6 makes us sad. Please don't use it
        xhttp = new ActiveXObject("Microsoft.XMLHTTP");
    }

    //handle request
    xhttp.onreadystatechange = function() {
        if (xhttp.readyState == 4) {
            var response = self.handleResponse(xhttp);
            callback(response);
        }
    };

    xhttp.open('POST',endpoint,true);
    xhttp.setRequestHeader('Content-type', 'text/xmlmc');
    //xhttp.setRequestHeader('Content-length', xml.length.toString());
    if(this.sessionCookie != '') {
        xhttp.setRequestHeader('Cookie', this.sessionCookie);
    }
    xhttp.send(xml);
};

The endpoint is localhost:5015

When I do this, the request fails and never even sends. When I use a standard request header like 'text/plain' the request is sent but returns a status code of 501 not implemented. How can I set a custom HTTP header in an xmlhttprequest?

Answer 1

It turns out this was due to a cross origin issue. Even when the domain is the same, if the ports are different it is a problem. I fixed the issue by adding a reverse proxy to my apache configuration and now I can query the api without cross origin requests. Unfortunately I don't have access to change the API and allow cross origin domains.