How to use Alamofire with custom headers for POST request

There is a simple solution to send parameters and header with a single Alamofire request for Swift 3 and Alamofire 4.0

    let url = "myURL"
    let parameters: Parameters = [
        "param1": "hello",
        "param2": "world"
    ]
    let headers = [
        "x-access-token": "myToken",
    ]

    Alamofire.request(url, method: .post, parameters: parameters, encoding: JSONEncoding.default, headers: headers).responseJSON { (response) in
        if response.result.isFailure {
            //In case of failure
        }else {
            //in case of success
        }
    }

Here's an example of how I use it with custom headers:

    var manager = Manager.sharedInstance
    // Specifying the Headers we need
    manager.session.configuration.HTTPAdditionalHeaders = [
        "Content-Type": "application/x-www-form-urlencoded",
        "Accept": "application/vnd.lichess.v1+json",
        "X-Requested-With": "XMLHttpRequest",
        "User-Agent": "iMchess"
    ]

Now whenever you make a request, it'll use the specified headers.

Your code refactored: remember to import Alamofire

    let aManager = Manager.sharedInstance
    manager.session.configuration.HTTPAdditionalHeaders = [
        "Authorization": "Bearer \(accessToken)" ]

    let URL =  url + "/server/rest/action"

    request(.POST, URL, encoding: .JSON)
        .responseJSON {
            (request, response, data, error) -> Void in

            println("REQUEST: \(request)")
            println("RESPONSE: \(response)")
            println("DATA: \(data)")
            println("ERROR: \(error)")
    }

This is request signature request(method: Method, URLString: URLStringConvertible>, parameters: [String : AnyObject]?, encoding: ParameterEncoding)

As you can see you don't have to pass an NSURL in it, just the string of the URL, Alamofire takes care of the rest.