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())
+			}
+		})
+	}
+}

modules/context/context.go

@@ -485,6 +485,31 @@ func GetContext(req *http.Request) *Context {
 	return req.Context().Value(contextKey).(*Context)
 }
 
+// SignedUserName returns signed user's name via context
+func SignedUserName(req *http.Request) string {
+	if middlewares.IsInternalPath(req) {
+		return ""
+	}
+	if middlewares.IsAPIPath(req) {
+		ctx, ok := req.Context().Value(apiContextKey).(*APIContext)
+		if ok {
+			v := ctx.Data["SignedUserName"]
+			if res, ok := v.(string); ok {
+				return res
+			}
+		}
+	} else {
+		ctx, ok := req.Context().Value(contextKey).(*Context)
+		if ok {
+			v := ctx.Data["SignedUserName"]
+			if res, ok := v.(string); ok {
+				return res
+			}
+		}
+	}
+	return ""
+}
+
 func getCsrfOpts() CsrfOptions {
 	return CsrfOptions{
 		Secret:         setting.SecretKey,

modules/context/response.go

@@ -12,6 +12,7 @@ type ResponseWriter interface {
 	Flush()
 	Status() int
 	Before(func(ResponseWriter))
+	Size() int
 }
 
 var (
@@ -21,11 +22,17 @@ var (
 // Response represents a response
 type Response struct {
 	http.ResponseWriter
+	written        int
 	status         int
 	befores        []func(ResponseWriter)
 	beforeExecuted bool
 }
 
+// Size return written size
+func (r *Response) Size() int {
+	return r.written
+}
+
 // Write writes bytes to HTTP endpoint
 func (r *Response) Write(bs []byte) (int, error) {
 	if !r.beforeExecuted {
@@ -35,8 +42,9 @@ func (r *Response) Write(bs []byte) (int, error) {
 		r.beforeExecuted = true
 	}
 	size, err := r.ResponseWriter.Write(bs)
+	r.written += size
 	if err != nil {
-		return 0, err
+		return size, err
 	}
 	if r.status == 0 {
 		r.WriteHeader(200)