Refactor response writer & access logger (#33323)

And add comments & tests

services/context/access_log_test.go

@@ -0,0 +1,75 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package context
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type testAccessLoggerMock struct {
+	logs []string
+}
+
+func (t *testAccessLoggerMock) Log(skip int, level log.Level, format string, v ...any) {
+	t.logs = append(t.logs, fmt.Sprintf(format, v...))
+}
+
+func (t *testAccessLoggerMock) GetLevel() log.Level {
+	return log.INFO
+}
+
+type testAccessLoggerResponseWriterMock struct{}
+
+func (t testAccessLoggerResponseWriterMock) Header() http.Header {
+	return nil
+}
+
+func (t testAccessLoggerResponseWriterMock) Before(f func(ResponseWriter)) {}
+
+func (t testAccessLoggerResponseWriterMock) WriteHeader(statusCode int) {}
+
+func (t testAccessLoggerResponseWriterMock) Write(bytes []byte) (int, error) {
+	return 0, nil
+}
+
+func (t testAccessLoggerResponseWriterMock) Flush() {}
+
+func (t testAccessLoggerResponseWriterMock) WrittenStatus() int {
+	return http.StatusOK
+}
+
+func (t testAccessLoggerResponseWriterMock) Status() int {
+	return t.WrittenStatus()
+}
+
+func (t testAccessLoggerResponseWriterMock) WrittenSize() int {
+	return 123123
+}
+
+func TestAccessLogger(t *testing.T) {
+	setting.Log.AccessLogTemplate = `{{.Ctx.RemoteHost}} - {{.Identity}} {{.Start.Format "[02/Jan/2006:15:04:05 -0700]" }} "{{.Ctx.Req.Method}} {{.Ctx.Req.URL.RequestURI}} {{.Ctx.Req.Proto}}" {{.ResponseWriter.Status}} {{.ResponseWriter.Size}} "{{.Ctx.Req.Referer}}" "{{.Ctx.Req.UserAgent}}"`
+	recorder := newAccessLogRecorder()
+	mockLogger := &testAccessLoggerMock{}
+	recorder.logger = mockLogger
+	req := &http.Request{
+		RemoteAddr: "remote-addr",
+		Method:     "GET",
+		Proto:      "https",
+		URL:        &url.URL{Path: "/path"},
+	}
+	req.Header = http.Header{}
+	req.Header.Add("Referer", "referer")
+	req.Header.Add("User-Agent", "user-agent")
+	recorder.record(time.Date(2000, 1, 2, 3, 4, 5, 0, time.UTC), &testAccessLoggerResponseWriterMock{}, req)
+	assert.Equal(t, []string{`remote-addr - - [02/Jan/2000:03:04:05 +0000] "GET /path https" 200 123123 "referer" "user-agent"`}, mockLogger.logs)
+}