package replacepathregex import ( "context" "fmt" "net/http" "regexp" "strings" "github.com/containous/traefik/pkg/config" "github.com/containous/traefik/pkg/middlewares" "github.com/containous/traefik/pkg/middlewares/replacepath" "github.com/containous/traefik/pkg/tracing" "github.com/opentracing/opentracing-go/ext" ) const ( typeName = "ReplacePathRegex" ) // ReplacePathRegex is a middleware used to replace the path of a URL request with a regular expression. type replacePathRegex struct { next http.Handler regexp *regexp.Regexp replacement string name string } // New creates a new replace path regex middleware. func New(ctx context.Context, next http.Handler, config config.ReplacePathRegex, name string) (http.Handler, error) { middlewares.GetLogger(ctx, name, typeName).Debug("Creating middleware") exp, err := regexp.Compile(strings.TrimSpace(config.Regex)) if err != nil { return nil, fmt.Errorf("error compiling regular expression %s: %s", config.Regex, err) } return &replacePathRegex{ regexp: exp, replacement: strings.TrimSpace(config.Replacement), next: next, name: name, }, nil } func (rp *replacePathRegex) GetTracingInformation() (string, ext.SpanKindEnum) { return rp.name, tracing.SpanKindNoneEnum } func (rp *replacePathRegex) ServeHTTP(rw http.ResponseWriter, req *http.Request) { if rp.regexp != nil && len(rp.replacement) > 0 && rp.regexp.MatchString(req.URL.Path) { req.Header.Add(replacepath.ReplacedPathHeader, req.URL.Path) req.URL.Path = rp.regexp.ReplaceAllString(req.URL.Path, rp.replacement) req.RequestURI = req.URL.RequestURI() } rp.next.ServeHTTP(rw, req) }