Support authentication tokens (through TransformRequest)

[bchretien]

New Feature

Some layers may require authentication tokens to be properly displayed in Mapbox. With mapbox-gl-js, we can use TransformRequest to do that easily (see https://docs.mapbox.com/mapbox-gl-js/api/properties/#requestparameters). Looking at the documentation, this does not seem possible in mapbox-maps-ios.

Why

Without this, we cannot display layers that require some form of authentication (e.g. bearer tokens passed in headers).

[DannyElinext]

I have the same problem, when I try to draw an image which requires an authentication token in header on the Mapbox through SourceType like ImageSource, VectorSource or RasterSource, then it didn't work and showed this error "[Error, maps-core]: {}[Style]: Failed to load source image_source_102: Invalid value. at offset 0". But it can work with an image that can be opened free on a browser. While Android can run normally with that requirement.

[OdNairy]

Hi there
The HttpServiceInterceptorInterface could help you with custom access tokens. I've made a basic sample for you:

final class DebugViewController: UIViewController {

    var mapView: MapView!

    var cancellables: Set<AnyCancelable> = []

    override func viewDidLoad() {
        super.viewDidLoad()
        mapView = MapView(frame: view.bounds)
        mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.insertSubview(mapView, at: 0)

        addHTTPInterceptor()
    }

    func addHTTPInterceptor() {
        HttpServiceFactory.setHttpServiceInterceptorForInterceptor(SampleHTTPInterceptor())
    }
}

class SampleHTTPInterceptor: HttpServiceInterceptorInterface {
    func onRequest(for request: HttpRequest, continuation: @escaping HttpServiceInterceptorRequestContinuation) {
        request.headers["Sample-Header"] = "Sample-Value"
        continuation(HttpRequestOrResponse.fromHttpRequest(request))
    }

    func onResponse(for response: HttpResponse, continuation: @escaping HttpServiceInterceptorResponseContinuation) {
        continuation(response)
    }
}

Pay attention that setHttpServiceInterceptorForInterceptor would preserve a strong reference to your interceptor.