From 3dbd5dcf6e134d8b12875700dfc1c8d3f19dccb2 Mon Sep 17 00:00:00 2001
From: chotow <i@choyri.com>
Date: Fri, 24 Jul 2020 22:01:19 +0800
Subject: [PATCH] Fixes the uses of caret(^) at the beginning of the rewrite
 regex

---
 middleware/rewrite.go      |  3 +++
 middleware/rewrite_test.go | 27 +++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/middleware/rewrite.go b/middleware/rewrite.go
index d1387af0..476023f6 100644
--- a/middleware/rewrite.go
+++ b/middleware/rewrite.go
@@ -59,6 +59,9 @@ func RewriteWithConfig(config RewriteConfig) echo.MiddlewareFunc {
 	for k, v := range config.Rules {
 		k = regexp.QuoteMeta(k)
 		k = strings.Replace(k, `\*`, "(.*)", -1)
+		if strings.HasPrefix(k, `\^`) {
+			k = strings.Replace(k, `\^`, "^", -1)
+		}
 		k = k + "$"
 		config.rulesRegex[regexp.MustCompile(k)] = v
 	}
diff --git a/middleware/rewrite_test.go b/middleware/rewrite_test.go
index eb5a46d8..848f0029 100644
--- a/middleware/rewrite_test.go
+++ b/middleware/rewrite_test.go
@@ -94,3 +94,30 @@ func TestRewriteWithConfigPreMiddleware_Issue1143(t *testing.T) {
 		assert.Equal(t, "hosts", string(bodyBytes))
 	}
 }
+
+// Issue #1573
+func TestEchoRewriteWithCaret(t *testing.T) {
+	e := echo.New()
+
+	e.Pre(RewriteWithConfig(RewriteConfig{
+		Rules: map[string]string{
+			"^/abc/*": "/v1/abc/$1",
+		},
+	}))
+
+	rec := httptest.NewRecorder()
+
+	var req *http.Request
+
+	req = httptest.NewRequest(http.MethodGet, "/abc/test", nil)
+	e.ServeHTTP(rec, req)
+	assert.Equal(t, "/v1/abc/test", req.URL.Path)
+
+	req = httptest.NewRequest(http.MethodGet, "/v1/abc/test", nil)
+	e.ServeHTTP(rec, req)
+	assert.Equal(t, "/v1/abc/test", req.URL.Path)
+
+	req = httptest.NewRequest(http.MethodGet, "/v2/abc/test", nil)
+	e.ServeHTTP(rec, req)
+	assert.Equal(t, "/v2/abc/test", req.URL.Path)
+}