Fix access log (#14475)

Fix #14121, #14478.

The `AccessLog` middleware has to be after `Contexter` or `APIContexter` so that we can get `LoginUserName` if possible.
And also there is a **BREAK** change that it removed internal API access log.

modules/context/access_log.go

@@ -0,0 +1,60 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package context
+
+import (
+	"bytes"
+	"html/template"
+	"net/http"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+)
+
+type routerLoggerOptions struct {
+	req            *http.Request
+	Identity       *string
+	Start          *time.Time
+	ResponseWriter http.ResponseWriter
+	Ctx            map[string]interface{}
+}
+
+// AccessLogger returns a middleware to log access logger
+func AccessLogger() func(http.Handler) http.Handler {
+	logger := log.GetLogger("access")
+	logTemplate, _ := template.New("log").Parse(setting.AccessLogTemplate)
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			start := time.Now()
+			next.ServeHTTP(w, req)
+			identity := "-"
+			if val := SignedUserName(req); val != "" {
+				identity = val
+			}
+			rw := w.(ResponseWriter)
+
+			buf := bytes.NewBuffer([]byte{})
+			err := logTemplate.Execute(buf, routerLoggerOptions{
+				req:            req,
+				Identity:       &identity,
+				Start:          &start,
+				ResponseWriter: rw,
+				Ctx: map[string]interface{}{
+					"RemoteAddr": req.RemoteAddr,
+					"Req":        req,
+				},
+			})
+			if err != nil {
+				log.Error("Could not set up chi access logger: %v", err.Error())
+			}
+
+			err = logger.SendLog(log.INFO, "", "", 0, buf.String(), "")
+			if err != nil {
+				log.Error("Could not set up chi access logger: %v", err.Error())
+			}
+		})
+	}
+}