URL encoding includes parameter names such as "$skip"

Hi All,

I have the folloging feign client:

@FeignClient(name = "MdsDataClient", url = "${integration.mds.host.url}", decode404 = true)
public interface MdsClient {

    @GetMapping(value = "{path}")
    Response get(
            @PathVariable("path") String path,
            @SpringQueryMap(encoded = true) Map<String, String> params,
            @RequestHeader Map<String, String> headerMap);

}

One of the defined parameters of the provided service is called "$skip".

Instead of GET https://services.com/currency/api/v2?rateType=DQ&from=USD&to=EUR&dateFrom=2012-01-01&dateTo=2012-01-01&$top=1&$skip=0, I end up with the following URI https://services.com/currency/api/v2?rateType=DQ&from=USD&to=EUR&dateFrom=2012-01-01&dateTo=2012-01-01&%24top=1&%24skip=0

I also tried the encoded = true setting on the @SpringQueryMap, but that seems to be take only the values and not the keys into account.

Any insights? A bug? By design? Thanks.

Start by reproducing the request from the MdsClient interface with parameter names such as "$skip" and "$top", comparing encoded=true with the observed URI. Trace the query-map encoding behavior and determine whether parameter names should remain unescaped; done means the behavior is clarified through a fix or documented design decision, with a regression check if the project provides one.