Allow overriding user agent in HTTP requests

[akirmse]

I have a RasterSource that is restricted to only certain User-Agent strings. This is a common anti-scraping measure for tiles stored on e.g. AWS. Not 100% effective, of course, but enough to keep out Web crawlers and most scripts.

I would like to set the User-Agent on HTTP requests from the Mapbox library. I do see a reference to replacing the entire HTTP stack in the Mapbox documentation (https://docs.mapbox.com/android/beta/maps/guides/migrate-to-v10/), but that's massive overkill, and anyway, this is the only reference to com.mapbox.common.HttpServiceInterface on the whole Internet, so I'm not sure that it's actually supported and used by clients.

There is a similar feature request for the Mapbox iOS SDK where it sounds like support is coming soon: mapbox/mapbox-maps-ios#435

This is easy to do in the Google Maps SDK for both Android and iOS, as the interface is a callback that lets you run arbitrary code to fetch a tile (a much preferable interface that would solve this and many other tile fetching issues).

[kiryldz]

Hey @akirmse!
Changes described here will land in Android at the same time as in iOS.

[kiryldz]

Adding interceptor landed in https://github.com/mapbox/mapbox-maps-android/releases/tag/android-v10.0.0-rc.8.

Sample code how to do that will be:

HttpServiceFactory.getInstance().setInterceptor(object : HttpServiceInterceptorInterface() {
  override fun onRequest(request: HttpRequest): HttpRequest {
    
  }

  override fun onDownload(download: DownloadOptions): DownloadOptions {
   
  }

  override fun onResponse(response: HttpResponse): HttpResponse {
    
  }
})