github.com/letsencrypt/boulder@v0.20251208.0/web/relative.go (about)

     1  package web
     2  
     3  import (
     4  	"net/http"
     5  	"net/url"
     6  )
     7  
     8  // RelativeEndpoint takes a path component of URL and constructs a new URL using
     9  // the host and port from the request combined the provided path.
    10  func RelativeEndpoint(request *http.Request, endpoint string) string {
    11  	var result string
    12  	proto := "http"
    13  	host := request.Host
    14  
    15  	// If the request was received via TLS, use `https://` for the protocol
    16  	if request.TLS != nil {
    17  		proto = "https"
    18  	}
    19  
    20  	// Allow upstream proxies  to specify the forwarded protocol. Allow this value
    21  	// to override our own guess.
    22  	if specifiedProto := request.Header.Get("X-Forwarded-Proto"); specifiedProto != "" {
    23  		proto = specifiedProto
    24  	}
    25  
    26  	// Default to "localhost" when no request.Host is provided. Otherwise requests
    27  	// with an empty `Host` produce results like `http:///acme/new-authz`
    28  	if request.Host == "" {
    29  		host = "localhost"
    30  	}
    31  
    32  	resultUrl := url.URL{Scheme: proto, Host: host, Path: endpoint}
    33  	result = resultUrl.String()
    34  
    35  	return result
    36  }