From 0e039a18684634a01aa3886a77c0a910e9678120 Mon Sep 17 00:00:00 2001
From: Abiola Ibrahim <abiola89@gmail.com>
Date: Sun, 20 Sep 2015 08:49:55 +0100
Subject: [PATCH 1/2] Rewrite: Use middleware.Replacer. Bug fix for regexps
 starting with '/'.

---
 middleware/replacer.go        | 10 ++++++++
 middleware/rewrite/rewrite.go | 43 ++++++++---------------------------
 2 files changed, 20 insertions(+), 33 deletions(-)

diff --git a/middleware/replacer.go b/middleware/replacer.go
index df1f6e010..9d34253cf 100644
--- a/middleware/replacer.go
+++ b/middleware/replacer.go
@@ -3,6 +3,7 @@ package middleware
 import (
 	"net"
 	"net/http"
+	"path"
 	"strconv"
 	"strings"
 	"time"
@@ -40,6 +41,7 @@ func NewReplacer(r *http.Request, rr *responseRecorder, emptyValue string) Repla
 			"{host}":     r.Host,
 			"{path}":     r.URL.Path,
 			"{query}":    r.URL.RawQuery,
+			"{frag}":     r.URL.Fragment,
 			"{fragment}": r.URL.Fragment,
 			"{proto}":    r.Proto,
 			"{remote}": func() string {
@@ -63,6 +65,14 @@ func NewReplacer(r *http.Request, rr *responseRecorder, emptyValue string) Repla
 			"{when}": func() string {
 				return time.Now().Format(timeFormat)
 			}(),
+			"{file}": func() string {
+				_, file := path.Split(r.URL.Path)
+				return file
+			}(),
+			"{dir}": func() string {
+				dir, _ := path.Split(r.URL.Path)
+				return dir
+			}(),
 		},
 		emptyValue: emptyValue,
 	}
diff --git a/middleware/rewrite/rewrite.go b/middleware/rewrite/rewrite.go
index bf987b938..ed2e9bd9f 100644
--- a/middleware/rewrite/rewrite.go
+++ b/middleware/rewrite/rewrite.go
@@ -3,9 +3,8 @@
 package rewrite
 
 import (
-	"net/http"
-
 	"fmt"
+	"net/http"
 	"net/url"
 	"path"
 	"path/filepath"
@@ -96,15 +95,6 @@ func NewRegexpRule(base, pattern, to string, ext []string) (*RegexpRule, error)
 	}, nil
 }
 
-// regexpVars are variables that can be used for To (rewrite destination path).
-var regexpVars = []string{
-	"{path}",
-	"{query}",
-	"{file}",
-	"{dir}",
-	"{frag}",
-}
-
 // Rewrite rewrites the internal location of the current request.
 func (r *RegexpRule) Rewrite(req *http.Request) bool {
 	rPath := req.URL.Path
@@ -119,32 +109,19 @@ func (r *RegexpRule) Rewrite(req *http.Request) bool {
 		return false
 	}
 
+	// include trailing slash in regexp if present
+	start := len(r.Base)
+	if strings.HasSuffix(r.Base, "/") {
+		start -= 1
+	}
+
 	// validate regexp
-	if !r.MatchString(rPath[len(r.Base):]) {
+	if !r.MatchString(rPath[start:]) {
 		return false
 	}
 
-	to := r.To
-
-	// check variables
-	for _, v := range regexpVars {
-		if strings.Contains(r.To, v) {
-			switch v {
-			case "{path}":
-				to = strings.Replace(to, v, req.URL.Path[1:], -1)
-			case "{query}":
-				to = strings.Replace(to, v, req.URL.RawQuery, -1)
-			case "{frag}":
-				to = strings.Replace(to, v, req.URL.Fragment, -1)
-			case "{file}":
-				_, file := path.Split(req.URL.Path)
-				to = strings.Replace(to, v, file, -1)
-			case "{dir}":
-				dir, _ := path.Split(req.URL.Path)
-				to = path.Clean(strings.Replace(to, v, dir, -1))
-			}
-		}
-	}
+	// replace variables
+	to := path.Clean(middleware.NewReplacer(req, nil, "").Replace(r.To))
 
 	// validate resulting path
 	url, err := url.Parse(to)

From 7f9fa5730b61064d26e723ff132a18ea79ce4f35 Mon Sep 17 00:00:00 2001
From: Abiola Ibrahim <abiola89@gmail.com>
Date: Sun, 20 Sep 2015 18:13:53 +0100
Subject: [PATCH 2/2] Rewrite: Use only `fragment`, remove `frag`.

---
 middleware/replacer.go             | 1 -
 middleware/rewrite/rewrite_test.go | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/middleware/replacer.go b/middleware/replacer.go
index 9d34253cf..29c695b77 100644
--- a/middleware/replacer.go
+++ b/middleware/replacer.go
@@ -41,7 +41,6 @@ func NewReplacer(r *http.Request, rr *responseRecorder, emptyValue string) Repla
 			"{host}":     r.Host,
 			"{path}":     r.URL.Path,
 			"{query}":    r.URL.RawQuery,
-			"{frag}":     r.URL.Fragment,
 			"{fragment}": r.URL.Fragment,
 			"{proto}":    r.Proto,
 			"{remote}": func() string {
diff --git a/middleware/rewrite/rewrite_test.go b/middleware/rewrite/rewrite_test.go
index d9056b431..b4845f106 100644
--- a/middleware/rewrite/rewrite_test.go
+++ b/middleware/rewrite/rewrite_test.go
@@ -28,7 +28,7 @@ func TestRewrite(t *testing.T) {
 		[]string{"/ab/", "ab", "/ab?type=html&{query}", ".html|"},
 		[]string{"/abc/", "ab", "/abc/{file}", ".html|"},
 		[]string{"/abcd/", "ab", "/a/{dir}/{file}", ".html|"},
-		[]string{"/abcde/", "ab", "/a#{frag}", ".html|"},
+		[]string{"/abcde/", "ab", "/a#{fragment}", ".html|"},
 		[]string{"/ab/", `.*\.jpg`, "/ajpg", ""},
 	}