Merge 53f0942 into 9734546

request.go

@@ -18,6 +18,9 @@ type XMLCharDecoder func(charset string, input io.Reader) (io.Reader, error)
 // ReqModifierFunc represent the function interface for request modifiers.
 type ReqModifierFunc func(*RequestModifier)
 
+// Filter defines whether a RequestModifier should be applied or not.
+type Filter func(*http.Request) bool
+
 // RequestModifier implements a convenient abstraction to modify an http.Request,
 // including methods to read, decode/encode and define JSON/XML/String/Binary bodies
 // and modify HTTP headers.
@@ -172,22 +175,34 @@ func (s *RequestModifier) Reader(body io.Reader) error {
 // RequestInterceptor interceps a given http.Request using a custom request modifier function.
 type RequestInterceptor struct {
 	Modifier ReqModifierFunc
+	Filters  []Filter
 }
 
 // Request intercepts an HTTP request and passes it to the given request modifier function.
 func Request(h ReqModifierFunc) *RequestInterceptor {
-	return &RequestInterceptor{Modifier: h}
+	return &RequestInterceptor{Modifier: h, Filters: []Filter{}}
+}
+
+// Filter intercepts an HTTP requests if and only if the given filter returns true.
+func (s *RequestInterceptor) Filter(f ...Filter) {
+	s.Filters = append(s.Filters, f...)
 }
 
 // HandleHTTP handles the middleware call chain, intercepting the request data if possible.
 // This methods implements the middleware layer compatible interface.
 func (s *RequestInterceptor) HandleHTTP(w http.ResponseWriter, r *http.Request, h http.Handler) {
-	if r.Method == "HEAD" || r.Method == "OPTIONS" {
-		h.ServeHTTP(w, r)
-		return
+	if s.filter(r) {
+		req := NewRequestModifier(r)
+		s.Modifier(req)
 	}
+	h.ServeHTTP(w, r)
+}
 
-	req := NewRequestModifier(r)
-	s.Modifier(req)
-	h.ServeHTTP(w, req.Request)
+func (s RequestInterceptor) filter(req *http.Request) bool {
+	for _, filter := range s.Filters {
+		if !filter(req) {
+			return false
+		}
+	}
+	return true
 }

request_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/xml"
 	"errors"
 	"github.com/nbio/st"
+	"gopkg.in/vinci-proxy/utils.v0"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -338,3 +339,42 @@ func TestReaderWithStringReaderAsParameter(t *testing.T) {
 	body, _ := ioutil.ReadAll(req.Body)
 	st.Expect(t, string(body), "Hello")
 }
+
+func TestFilterWithRequestFilteredOut(t *testing.T) {
+	interceptor := interceptorWithFilters()
+	stubbedWriter := utils.NewWriterStub()
+	req := &http.Request{Method: "POST"}
+	handler := http.HandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
+		st.Expect(t, r.Header.Get("intercepted"), "")
+	})
+	interceptor.HandleHTTP(stubbedWriter, req, handler)
+}
+
+func TestFilterWithRequestFilteredIn(t *testing.T) {
+	interceptor := interceptorWithFilters()
+	stubbedWriter := utils.NewWriterStub()
+	req := &http.Request{Method: "POST", Header: http.Header{}}
+	req.Header.Set("filter2", "true")
+	req.Header.Set("filter3", "true")
+	handler := http.HandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
+		st.Expect(t, r.Header.Get("intercepted"), "true")
+	})
+	interceptor.HandleHTTP(stubbedWriter, req, handler)
+}
+
+func interceptorWithFilters() *RequestInterceptor {
+	interceptor := Request(func(m *RequestModifier) {
+		m.Header.Set("intercepted", "true")
+	})
+	filter1 := func(r *http.Request) bool {
+		return r.Method == "POST"
+	}
+	filter2 := func(r *http.Request) bool {
+		return r.Header.Get("filter2") == "true"
+	}
+	interceptor.Filter(filter1, filter2)
+	interceptor.Filter(func(r *http.Request) bool {
+		return r.Header.Get("filter3") == "true"
+	})
+	return interceptor
+}