Use standard HTTP library to serve files (#24693)

`http.ServeFile/ServeContent` handles `If-xxx`, `Content-Length`,
`Range` and `Etag` correctly

After this PR, storage files (eg: avatar) could be responded with
correct Content-Length.

2 files changed, 7 insertions, 41 deletions

diff --git a/modules/httplib/mock.go b/modules/httplib/mock.go
deleted file mode 100644
index 7d284e86fb..0000000000
--- a/modules/httplib/mock.go
+++ /dev/null
@@ -1,35 +0,0 @@
-// Copyright 2023 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package httplib
-
-import (
-	"bytes"
-	"net/http"
-)
-
-type MockResponseWriter struct {
-	header http.Header
-
-	StatusCode int
-	BodyBuffer bytes.Buffer
-}
-
-func (m *MockResponseWriter) Header() http.Header {
-	return m.header
-}
-
-func (m *MockResponseWriter) Write(bytes []byte) (int, error) {
-	if m.StatusCode == 0 {
-		m.StatusCode = http.StatusOK
-	}
-	return m.BodyBuffer.Write(bytes)
-}
-
-func (m *MockResponseWriter) WriteHeader(statusCode int) {
-	m.StatusCode = statusCode
-}
-
-func NewMockResponseWriter() *MockResponseWriter {
-	return &MockResponseWriter{header: http.Header{}}
-}
diff --git a/modules/httplib/serve_test.go b/modules/httplib/serve_test.go
index 0768f1c713..fed4611d21 100644
--- a/modules/httplib/serve_test.go
+++ b/modules/httplib/serve_test.go
@@ -6,6 +6,7 @@ package httplib
 import (
 	"fmt"
 	"net/http"
+	"net/http/httptest"
 	"net/url"
 	"os"
 	"strings"
@@ -25,12 +26,12 @@ func TestServeContentByReader(t *testing.T) {
 			r.Header.Set("Range", fmt.Sprintf("bytes=%s", rangeStr))
 		}
 		reader := strings.NewReader(data)
-		w := NewMockResponseWriter()
+		w := httptest.NewRecorder()
 		ServeContentByReader(r, w, "test", int64(len(data)), reader)
-		assert.Equal(t, expectedStatusCode, w.StatusCode)
+		assert.Equal(t, expectedStatusCode, w.Code)
 		if expectedStatusCode == http.StatusPartialContent || expectedStatusCode == http.StatusOK {
 			assert.Equal(t, fmt.Sprint(len(expectedContent)), w.Header().Get("Content-Length"))
-			assert.Equal(t, expectedContent, w.BodyBuffer.String())
+			assert.Equal(t, expectedContent, w.Body.String())
 		}
 	}
 
@@ -76,12 +77,12 @@ func TestServeContentByReadSeeker(t *testing.T) {
 		}
 		defer seekReader.Close()
 
-		w := NewMockResponseWriter()
+		w := httptest.NewRecorder()
 		ServeContentByReadSeeker(r, w, "test", time.Time{}, seekReader)
-		assert.Equal(t, expectedStatusCode, w.StatusCode)
+		assert.Equal(t, expectedStatusCode, w.Code)
 		if expectedStatusCode == http.StatusPartialContent || expectedStatusCode == http.StatusOK {
 			assert.Equal(t, fmt.Sprint(len(expectedContent)), w.Header().Get("Content-Length"))
-			assert.Equal(t, expectedContent, w.BodyBuffer.String())
+			assert.Equal(t, expectedContent, w.Body.String())
 		}
 	}