Create Header Middleware

middlewares/headers.go

@@ -0,0 +1,79 @@
+package middlewares
+
+//Middleware based on https://github.com/unrolled/secure
+
+import (
+	"github.com/containous/traefik/types"
+	"net/http"
+)
+
+// HeaderOptions is a struct for specifying configuration options for the headers middleware.
+type HeaderOptions struct {
+	// If Custom request headers are set, these will be added to the request
+	CustomRequestHeaders map[string]string
+	// If Custom response headers are set, these will be added to the ResponseWriter
+	CustomResponseHeaders map[string]string
+}
+
+// HeaderStruct is a middleware that helps setup a few basic security features. A single headerOptions struct can be
+// provided to configure which features should be enabled, and the ability to override a few of the default values.
+type HeaderStruct struct {
+	// Customize headers with a headerOptions struct.
+	opt HeaderOptions
+}
+
+// NewHeaderFromStruct constructs a new header instance from supplied frontend header struct.
+func NewHeaderFromStruct(headers types.Headers) *HeaderStruct {
+	o := HeaderOptions{
+		CustomRequestHeaders:  headers.CustomRequestHeaders,
+		CustomResponseHeaders: headers.CustomResponseHeaders,
+	}
+
+	return &HeaderStruct{
+		opt: o,
+	}
+}
+
+// NewHeader constructs a new header instance with supplied options.
+func NewHeader(options ...HeaderOptions) *HeaderStruct {
+	var o HeaderOptions
+	if len(options) == 0 {
+		o = HeaderOptions{}
+	} else {
+		o = options[0]
+	}
+
+	return &HeaderStruct{
+		opt: o,
+	}
+}
+
+// Handler implements the http.HandlerFunc for integration with the standard net/http lib.
+func (s *HeaderStruct) Handler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Let headers process the request.
+		s.Process(w, r)
+		h.ServeHTTP(w, r)
+	})
+}
+
+func (s *HeaderStruct) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
+	s.Process(w, r)
+	// If there is a next, call it.
+	if next != nil {
+		next(w, r)
+	}
+}
+
+// Process runs the actual checks and returns an error if the middleware chain should stop.
+func (s *HeaderStruct) Process(w http.ResponseWriter, r *http.Request) {
+	// Loop through Custom request headers
+	for header, value := range s.opt.CustomRequestHeaders {
+		r.Header.Set(header, value)
+	}
+
+	// Loop through Custom response headers
+	for header, value := range s.opt.CustomResponseHeaders {
+		w.Header().Add(header, value)
+	}
+}