// Copyright 2020 The Gitea Authors. All rights reserved.// SPDX-License-Identifier: MIT package context import (	"bytes"	"fmt"	"net"	"net/http"	"strings"	"text/template"	"time" 	user_model "forgejo.org/models/user"	"forgejo.org/modules/log"	"forgejo.org/modules/setting"	"forgejo.org/modules/web/middleware") type routerLoggerOptions struct {	req            *http.Request	Identity       *string	Start          *time.Time	ResponseWriter http.ResponseWriter	Ctx            map[string]any	RequestID      *string} const keyOfRequestIDInTemplate = ".RequestID" // According to:// TraceId: A valid trace identifier is a 16-byte array with at least one non-zero byte// MD5 output is 16 or 32 bytes: md5-bytes is 16, md5-hex is 32// SHA1: similar, SHA1-bytes is 20, SHA1-hex is 40.// UUID is 128-bit, 32 hex chars, 36 ASCII chars with 4 dashes// So, we accept a Request ID with a maximum character length of 40const maxRequestIDByteLength = 40 func parseRequestIDFromRequestHeader(req *http.Request) string {	requestID := "-"	for _, key := range setting.Log.RequestIDHeaders {		if req.Header.Get(key) != "" {			requestID = req.Header.Get(key)			break		}	}	if len(requestID) > maxRequestIDByteLength {		requestID = fmt.Sprintf("%s...", requestID[:maxRequestIDByteLength])	}	return requestID} // AccessLogger returns a middleware to log access loggerfunc AccessLogger() func(http.Handler) http.Handler {	logger := log.GetLogger("access")	needRequestID := len(setting.Log.RequestIDHeaders) > 0 && strings.Contains(setting.Log.AccessLogTemplate, keyOfRequestIDInTemplate)	logTemplate, _ := template.New("log").Parse(setting.Log.AccessLogTemplate)	return func(next http.Handler) http.Handler {		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {			start := time.Now() 			var requestID string			if needRequestID {				requestID = parseRequestIDFromRequestHeader(req)			} 			reqHost, _, err := net.SplitHostPort(req.RemoteAddr)			if err != nil {				reqHost = req.RemoteAddr			} 			next.ServeHTTP(w, req)			rw := w.(ResponseWriter) 			identity := "-"			data := middleware.GetContextData(req.Context())			if signedUser, ok := data[middleware.ContextDataKeySignedUser].(*user_model.User); ok {				identity = signedUser.Name			}			buf := bytes.NewBuffer([]byte{})			err = logTemplate.Execute(buf, routerLoggerOptions{				req:            req,				Identity:       &identity,				Start:          &start,				ResponseWriter: rw,				Ctx: map[string]any{					"RemoteAddr": req.RemoteAddr,					"RemoteHost": reqHost,					"Req":        req,				},				RequestID: &requestID,			})			if err != nil {				log.Error("Could not execute access logger template: %v", err.Error())			} 			logger.Info("%s", buf.String())		})	}}