MakeAuthAPI turns a util.JSONRequestHandler function into an http.Handler which authenticates the request.

MakeExternalAPI turns a util.JSONRequestHandler function into an http.Handler.

MakeHTMLAPI adds Span metrics to the HTML Handler function This is used to serve HTML alongside JSON error messages.

MakeInternalAPI turns a util.JSONRequestHandler function into an http.Handler.

MakeLocalAPI localhost，localhost.

PostJSON performs a POST request with JSON on an internal HTTP API.

URLDecodeMapValues is a function that iterates through each of the items in a map, URL decodes the value, and returns a new map with the decoded values under the same key names.

WrapHandlerInBasicAuth adds basic auth to a handler.

WrapHandlerInCORS adds CORS headers to all responses, including all error responses.

BasicAuth is used for authorization on /metrics handlers.