Move macaron to chi (#14293)

Use [chi](https://github.com/go-chi/chi) instead of the forked [macaron](https://gitea.com/macaron/macaron). Since macaron and chi have conflicts with session share, this big PR becomes a have-to thing. According my previous idea, we can replace macaron step by step but I'm wrong. :( Below is a list of big changes on this PR.

- [x] Define `context.ResponseWriter` interface with an implementation `context.Response`.
- [x] Use chi instead of macaron, and also a customize `Route` to wrap chi so that the router usage is similar as before.
- [x] Create different routers for `web`, `api`, `internal` and `install` so that the codes will be more clear and no magic .
- [x] Use https://github.com/unrolled/render instead of macaron's internal render
- [x] Use https://github.com/NYTimes/gziphandler instead of https://gitea.com/macaron/gzip
- [x] Use https://gitea.com/go-chi/session which is a modified version of https://gitea.com/macaron/session and removed `nodb` support since it will not be maintained. **BREAK**
- [x] Use https://gitea.com/go-chi/captcha which is a modified version of https://gitea.com/macaron/captcha
- [x] Use https://gitea.com/go-chi/cache which is a modified version of https://gitea.com/macaron/cache
- [x] Use https://gitea.com/go-chi/binding which is a modified version of https://gitea.com/macaron/binding
- [x] Use https://github.com/go-chi/cors instead of https://gitea.com/macaron/cors
- [x] Dropped https://gitea.com/macaron/i18n and make a new one in `code.gitea.io/gitea/modules/translation`
- [x] Move validation form structs from `code.gitea.io/gitea/modules/auth` to `code.gitea.io/gitea/modules/forms` to avoid dependency cycle.
- [x] Removed macaron log service because it's not need any more. **BREAK**
- [x] All form structs have to be get by `web.GetForm(ctx)` in the route function but not as a function parameter on routes definition.
- [x] Move Git HTTP protocol implementation to use routers directly.
- [x] Fix the problem that chi routes don't support trailing slash but macaron did.
- [x] `/api/v1/swagger` now will be redirect to `/api/swagger` but not render directly so that `APIContext` will not create a html render. 

Notices:
- Chi router don't support request with trailing slash
- Integration test `TestUserHeatmap` maybe mysql version related. It's failed on my macOS(mysql 5.7.29 installed via brew) but succeed on CI.

Co-authored-by: 6543 <6543@obermui.de>

routers/routes/base.go

@@ -0,0 +1,246 @@
+// 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 routes
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"strings"
+	"text/template"
+	"time"
+
+	"code.gitea.io/gitea/modules/auth/sso"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/httpcache"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/middlewares"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/storage"
+	"code.gitea.io/gitea/modules/templates"
+
+	"gitea.com/go-chi/session"
+)
+
+type routerLoggerOptions struct {
+	req            *http.Request
+	Identity       *string
+	Start          *time.Time
+	ResponseWriter http.ResponseWriter
+}
+
+// SignedUserName returns signed user's name via context
+func SignedUserName(req *http.Request) string {
+	ctx := context.GetContext(req)
+	if ctx != nil {
+		v := ctx.Data["SignedUserName"]
+		if res, ok := v.(string); ok {
+			return res
+		}
+	}
+	return ""
+}
+
+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
+
+			buf := bytes.NewBuffer([]byte{})
+			err := logTemplate.Execute(buf, routerLoggerOptions{
+				req:            req,
+				Identity:       &identity,
+				Start:          &start,
+				ResponseWriter: rw,
+			})
+			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())
+			}
+		})
+	}
+}
+
+// LoggerHandler is a handler that will log the routing to the default gitea log
+func LoggerHandler(level log.Level) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			start := time.Now()
+
+			_ = log.GetLogger("router").Log(0, level, "Started %s %s for %s", log.ColoredMethod(req.Method), req.URL.RequestURI(), req.RemoteAddr)
+
+			next.ServeHTTP(w, req)
+
+			var status int
+			if v, ok := w.(context.ResponseWriter); ok {
+				status = v.Status()
+			}
+
+			_ = log.GetLogger("router").Log(0, level, "Completed %s %s %v %s in %v", log.ColoredMethod(req.Method), req.URL.RequestURI(), log.ColoredStatus(status), log.ColoredStatus(status, http.StatusText(status)), log.ColoredTime(time.Since(start)))
+		})
+	}
+}
+
+func storageHandler(storageSetting setting.Storage, prefix string, objStore storage.ObjectStorage) func(next http.Handler) http.Handler {
+	return func(next http.Handler) http.Handler {
+		if storageSetting.ServeDirect {
+			return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+				if req.Method != "GET" && req.Method != "HEAD" {
+					next.ServeHTTP(w, req)
+					return
+				}
+
+				if !strings.HasPrefix(req.URL.RequestURI(), "/"+prefix) {
+					next.ServeHTTP(w, req)
+					return
+				}
+
+				rPath := strings.TrimPrefix(req.URL.RequestURI(), "/"+prefix)
+				u, err := objStore.URL(rPath, path.Base(rPath))
+				if err != nil {
+					if os.IsNotExist(err) || errors.Is(err, os.ErrNotExist) {
+						log.Warn("Unable to find %s %s", prefix, rPath)
+						http.Error(w, "file not found", 404)
+						return
+					}
+					log.Error("Error whilst getting URL for %s %s. Error: %v", prefix, rPath, err)
+					http.Error(w, fmt.Sprintf("Error whilst getting URL for %s %s", prefix, rPath), 500)
+					return
+				}
+				http.Redirect(
+					w,
+					req,
+					u.String(),
+					301,
+				)
+			})
+		}
+
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			if req.Method != "GET" && req.Method != "HEAD" {
+				next.ServeHTTP(w, req)
+				return
+			}
+
+			if !strings.HasPrefix(req.URL.RequestURI(), "/"+prefix) {
+				next.ServeHTTP(w, req)
+				return
+			}
+
+			rPath := strings.TrimPrefix(req.URL.RequestURI(), "/"+prefix)
+			rPath = strings.TrimPrefix(rPath, "/")
+
+			fi, err := objStore.Stat(rPath)
+			if err == nil && httpcache.HandleTimeCache(req, w, fi) {
+				return
+			}
+
+			//If we have matched and access to release or issue
+			fr, err := objStore.Open(rPath)
+			if err != nil {
+				if os.IsNotExist(err) || errors.Is(err, os.ErrNotExist) {
+					log.Warn("Unable to find %s %s", prefix, rPath)
+					http.Error(w, "file not found", 404)
+					return
+				}
+				log.Error("Error whilst opening %s %s. Error: %v", prefix, rPath, err)
+				http.Error(w, fmt.Sprintf("Error whilst opening %s %s", prefix, rPath), 500)
+				return
+			}
+			defer fr.Close()
+
+			_, err = io.Copy(w, fr)
+			if err != nil {
+				log.Error("Error whilst rendering %s %s. Error: %v", prefix, rPath, err)
+				http.Error(w, fmt.Sprintf("Error whilst rendering %s %s", prefix, rPath), 500)
+				return
+			}
+		})
+	}
+}
+
+type dataStore struct {
+	Data map[string]interface{}
+}
+
+func (d *dataStore) GetData() map[string]interface{} {
+	return d.Data
+}
+
+// Recovery returns a middleware that recovers from any panics and writes a 500 and a log if so.
+// This error will be created with the gitea 500 page.
+func Recovery() func(next http.Handler) http.Handler {
+	var rnd = templates.HTMLRenderer()
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			defer func() {
+				if err := recover(); err != nil {
+					combinedErr := fmt.Sprintf("PANIC: %v\n%s", err, string(log.Stack(2)))
+					log.Error("%v", combinedErr)
+
+					sessionStore := session.GetSession(req)
+					if sessionStore == nil {
+						if setting.IsProd() {
+							http.Error(w, http.StatusText(500), 500)
+						} else {
+							http.Error(w, combinedErr, 500)
+						}
+						return
+					}
+
+					var lc = middlewares.Locale(w, req)
+					var store = dataStore{
+						Data: templates.Vars{
+							"Language":   lc.Language(),
+							"CurrentURL": setting.AppSubURL + req.URL.RequestURI(),
+							"i18n":       lc,
+						},
+					}
+
+					// Get user from session if logged in.
+					user, _ := sso.SignedInUser(req, w, &store, sessionStore)
+					if user != nil {
+						store.Data["IsSigned"] = true
+						store.Data["SignedUser"] = user
+						store.Data["SignedUserID"] = user.ID
+						store.Data["SignedUserName"] = user.Name
+						store.Data["IsAdmin"] = user.IsAdmin
+					} else {
+						store.Data["SignedUserID"] = int64(0)
+						store.Data["SignedUserName"] = ""
+					}
+
+					w.Header().Set(`X-Frame-Options`, `SAMEORIGIN`)
+
+					if !setting.IsProd() {
+						store.Data["ErrorMsg"] = combinedErr
+					}
+					err = rnd.HTML(w, 500, "status/500", templates.BaseVars().Merge(store.Data))
+					if err != nil {
+						log.Error("%v", err)
+					}
+				}
+			}()
+
+			next.ServeHTTP(w, req)
+		})
+	}
+}