package stripprefix import ( "context" "net/http" "strings" "github.com/containous/traefik/config" "github.com/containous/traefik/middlewares" "github.com/containous/traefik/tracing" "github.com/opentracing/opentracing-go/ext" ) const ( // ForwardedPrefixHeader is the default header to set prefix. ForwardedPrefixHeader = "X-Forwarded-Prefix" typeName = "StripPrefix" ) // stripPrefix is a middleware used to strip prefix from an URL request. type stripPrefix struct { next http.Handler prefixes []string name string } // New creates a new strip prefix middleware. func New(ctx context.Context, next http.Handler, config config.StripPrefix, name string) (http.Handler, error) { middlewares.GetLogger(ctx, name, typeName).Debug("Creating middleware") return &stripPrefix{ prefixes: config.Prefixes, next: next, name: name, }, nil } func (s *stripPrefix) GetTracingInformation() (string, ext.SpanKindEnum) { return s.name, tracing.SpanKindNoneEnum } func (s *stripPrefix) ServeHTTP(rw http.ResponseWriter, req *http.Request) { for _, prefix := range s.prefixes { if strings.HasPrefix(req.URL.Path, prefix) { req.URL.Path = getPrefixStripped(req.URL.Path, prefix) if req.URL.RawPath != "" { req.URL.RawPath = getPrefixStripped(req.URL.RawPath, prefix) } s.serveRequest(rw, req, strings.TrimSpace(prefix)) return } } http.NotFound(rw, req) } func (s *stripPrefix) serveRequest(rw http.ResponseWriter, req *http.Request, prefix string) { req.Header.Add(ForwardedPrefixHeader, prefix) req.RequestURI = req.URL.RequestURI() s.next.ServeHTTP(rw, req) } func getPrefixStripped(s, prefix string) string { return ensureLeadingSlash(strings.TrimPrefix(s, prefix)) } func ensureLeadingSlash(str string) string { return "/" + strings.TrimPrefix(str, "/") }