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Beego/router.go
Pengfei Xue 76c0636125 beego.Context.Abort return immediately
* add common 4XX/5XX HTTP exceptions
2013-11-26 08:46:46 +08:00

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package beego
import (
"fmt"
beecontext "github.com/astaxie/beego/context"
"github.com/astaxie/beego/middleware"
"github.com/astaxie/beego/toolbox"
"net/http"
"net/url"
"os"
"reflect"
"regexp"
"runtime"
"strconv"
"strings"
"time"
)
const (
BeforeRouter = iota
AfterStatic
BeforeExec
AfterExec
FinishRouter
)
var HTTPMETHOD = []string{"get", "post", "put", "delete", "patch", "options", "head"}
type controllerInfo struct {
pattern string
regex *regexp.Regexp
params map[int]string
controllerType reflect.Type
methods map[string]string
hasMethod bool
}
type ControllerRegistor struct {
routers []*controllerInfo
fixrouters []*controllerInfo
enableFilter bool
filters map[int][]*FilterRouter
enableAuto bool
autoRouter map[string]map[string]reflect.Type //key:controller key:method value:reflect.type
}
func NewControllerRegistor() *ControllerRegistor {
return &ControllerRegistor{
routers: make([]*controllerInfo, 0),
autoRouter: make(map[string]map[string]reflect.Type),
filters: make(map[int][]*FilterRouter),
}
}
//methods support like this:
//default methods is the same name as method
//Add("/user",&UserController{})
//Add("/api/list",&RestController{},"*:ListFood")
//Add("/api/create",&RestController{},"post:CreateFood")
//Add("/api/update",&RestController{},"put:UpdateFood")
//Add("/api/delete",&RestController{},"delete:DeleteFood")
//Add("/api",&RestController{},"get,post:ApiFunc")
//Add("/simple",&SimpleController{},"get:GetFunc;post:PostFunc")
func (p *ControllerRegistor) Add(pattern string, c ControllerInterface, mappingMethods ...string) {
parts := strings.Split(pattern, "/")
j := 0
params := make(map[int]string)
for i, part := range parts {
if strings.HasPrefix(part, ":") {
expr := "(.+)"
//a user may choose to override the defult expression
// similar to expressjs: /user/:id([0-9]+)
if index := strings.Index(part, "("); index != -1 {
expr = part[index:]
part = part[:index]
//match /user/:id:int ([0-9]+)
//match /post/:username:string ([\w]+)
} else if lindex := strings.LastIndex(part, ":"); lindex != 0 {
switch part[lindex:] {
case ":int":
expr = "([0-9]+)"
part = part[:lindex]
case ":string":
expr = `([\w]+)`
part = part[:lindex]
}
}
params[j] = part
parts[i] = expr
j++
}
if strings.HasPrefix(part, "*") {
expr := "(.+)"
if part == "*.*" {
params[j] = ":path"
parts[i] = "([^.]+).([^.]+)"
j++
params[j] = ":ext"
j++
} else {
params[j] = ":splat"
parts[i] = expr
j++
}
}
//url like someprefix:id(xxx).html
if strings.Contains(part, ":") && strings.Contains(part, "(") && strings.Contains(part, ")") {
var out []rune
var start bool
var startexp bool
var param []rune
var expt []rune
for _, v := range part {
if start {
if v != '(' {
param = append(param, v)
continue
}
}
if startexp {
if v != ')' {
expt = append(expt, v)
continue
}
}
if v == ':' {
param = make([]rune, 0)
param = append(param, ':')
start = true
} else if v == '(' {
startexp = true
start = false
params[j] = string(param)
j++
expt = make([]rune, 0)
expt = append(expt, '(')
} else if v == ')' {
startexp = false
expt = append(expt, ')')
out = append(out, expt...)
} else {
out = append(out, v)
}
}
parts[i] = string(out)
}
}
reflectVal := reflect.ValueOf(c)
t := reflect.Indirect(reflectVal).Type()
methods := make(map[string]string)
if len(mappingMethods) > 0 {
semi := strings.Split(mappingMethods[0], ";")
for _, v := range semi {
colon := strings.Split(v, ":")
if len(colon) != 2 {
panic("method mapping fomate is error")
}
comma := strings.Split(colon[0], ",")
for _, m := range comma {
if m == "*" || inSlice(strings.ToLower(m), HTTPMETHOD) {
if val := reflectVal.MethodByName(colon[1]); val.IsValid() {
methods[strings.ToLower(m)] = colon[1]
} else {
panic(colon[1] + " method don't exist in the controller " + t.Name())
}
} else {
panic(v + " is an error method mapping,Don't exist method named " + m)
}
}
}
}
if j == 0 {
//now create the Route
route := &controllerInfo{}
route.pattern = pattern
route.controllerType = t
route.methods = methods
if len(methods) > 0 {
route.hasMethod = true
}
p.fixrouters = append(p.fixrouters, route)
} else { // add regexp routers
//recreate the url pattern, with parameters replaced
//by regular expressions. then compile the regex
pattern = strings.Join(parts, "/")
regex, regexErr := regexp.Compile(pattern)
if regexErr != nil {
//TODO add error handling here to avoid panic
panic(regexErr)
return
}
//now create the Route
route := &controllerInfo{}
route.regex = regex
route.params = params
route.pattern = pattern
route.methods = methods
if len(methods) > 0 {
route.hasMethod = true
}
route.controllerType = t
p.routers = append(p.routers, route)
}
}
func (p *ControllerRegistor) AddAuto(c ControllerInterface) {
p.enableAuto = true
reflectVal := reflect.ValueOf(c)
rt := reflectVal.Type()
ct := reflect.Indirect(reflectVal).Type()
firstParam := strings.ToLower(strings.TrimSuffix(ct.Name(), "Controller"))
if _, ok := p.autoRouter[firstParam]; ok {
return
} else {
p.autoRouter[firstParam] = make(map[string]reflect.Type)
}
for i := 0; i < rt.NumMethod(); i++ {
p.autoRouter[firstParam][rt.Method(i).Name] = ct
}
}
func buildFilter(pattern string, filter FilterFunc) *FilterRouter {
mr := new(FilterRouter)
mr.filterFunc = filter
parts := strings.Split(pattern, "/")
j := 0
for i, part := range parts {
if strings.HasPrefix(part, ":") {
expr := "(.+)"
//a user may choose to override the default expression
// similar to expressjs: /user/:id([0-9]+)
if index := strings.Index(part, "("); index != -1 {
expr = part[index:]
part = part[:index]
//match /user/:id:int ([0-9]+)
//match /post/:username:string ([\w]+)
} else if lindex := strings.LastIndex(part, ":"); lindex != 0 {
switch part[lindex:] {
case ":int":
expr = "([0-9]+)"
part = part[:lindex]
case ":string":
expr = `([\w]+)`
part = part[:lindex]
}
}
parts[i] = expr
j++
}
}
if j != 0 {
pattern = strings.Join(parts, "/")
regex, regexErr := regexp.Compile(pattern)
if regexErr != nil {
//TODO add error handling here to avoid panic
panic(regexErr)
}
mr.regex = regex
mr.hasregex = true
}
mr.pattern = pattern
return mr
}
func (p *ControllerRegistor) AddFilter(pattern, action string, filter FilterFunc) {
mr := buildFilter(pattern, filter)
switch action {
case "BeforRouter":
p.filters[BeforeRouter] = append(p.filters[BeforeRouter], mr)
case "AfterStatic":
p.filters[AfterStatic] = append(p.filters[AfterStatic], mr)
case "BeforeExec":
p.filters[BeforeExec] = append(p.filters[BeforeExec], mr)
case "AfterExec":
p.filters[AfterExec] = append(p.filters[AfterExec], mr)
case "FinishRouter":
p.filters[FinishRouter] = append(p.filters[FinishRouter], mr)
}
p.enableFilter = true
}
func (p *ControllerRegistor) InsertFilter(pattern string, pos int, filter FilterFunc) {
mr := buildFilter(pattern, filter)
p.filters[pos] = append(p.filters[pos], mr)
p.enableFilter = true
}
func (p *ControllerRegistor) UrlFor(endpoint string, values ...string) string {
paths := strings.Split(endpoint, ".")
if len(paths) <= 1 {
Warn("urlfor endpoint must like path.controller.method")
return ""
}
if len(values)%2 != 0 {
Warn("urlfor params must key-value pair")
return ""
}
urlv := url.Values{}
if len(values) > 0 {
key := ""
for k, v := range values {
if k%2 == 0 {
key = v
} else {
urlv.Set(key, v)
}
}
}
controllName := strings.Join(paths[:len(paths)-1], ".")
methodName := paths[len(paths)-1]
for _, route := range p.fixrouters {
if route.controllerType.Name() == controllName {
var finded bool
if inSlice(strings.ToLower(methodName), HTTPMETHOD) {
if route.hasMethod {
if m, ok := route.methods[strings.ToLower(methodName)]; ok && m != methodName {
finded = false
} else if m, ok = route.methods["*"]; ok && m != methodName {
finded = false
} else {
finded = true
}
} else {
finded = true
}
} else if route.hasMethod {
for _, md := range route.methods {
if md == methodName {
finded = true
}
}
}
if !finded {
continue
}
if len(values) > 0 {
return route.pattern + "?" + urlv.Encode()
}
return route.pattern
}
}
for _, route := range p.routers {
if route.controllerType.Name() == controllName {
var finded bool
if inSlice(strings.ToLower(methodName), HTTPMETHOD) {
if route.hasMethod {
if m, ok := route.methods[strings.ToLower(methodName)]; ok && m != methodName {
finded = false
} else if m, ok = route.methods["*"]; ok && m != methodName {
finded = false
} else {
finded = true
}
} else {
finded = true
}
} else if route.hasMethod {
for _, md := range route.methods {
if md == methodName {
finded = true
}
}
}
if !finded {
continue
}
var returnurl string
var i int
var startreg bool
for _, v := range route.regex.String() {
if v == '(' {
startreg = true
continue
} else if v == ')' {
startreg = false
returnurl = returnurl + urlv.Get(route.params[i])
i++
} else if !startreg {
returnurl = string(append([]rune(returnurl), v))
}
}
if route.regex.MatchString(returnurl) {
return returnurl
}
}
}
if p.enableAuto {
for cName, methodList := range p.autoRouter {
if strings.ToLower(strings.TrimSuffix(paths[len(paths)-2], "Controller")) == cName {
if _, ok := methodList[methodName]; ok {
if len(values) > 0 {
return "/" + strings.TrimSuffix(paths[len(paths)-2], "Controller") + "/" + methodName + "?" + urlv.Encode()
} else {
return "/" + strings.TrimSuffix(paths[len(paths)-2], "Controller") + "/" + methodName
}
}
}
}
}
return ""
}
// AutoRoute
func (p *ControllerRegistor) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
defer func() {
if err := recover(); err != nil {
if _, ok := err.(middleware.HTTPException); ok {
// catch intented errors, only for HTTP 4XX and 5XX
} else {
errstr := fmt.Sprint(err)
if handler, ok := middleware.ErrorMaps[errstr]; ok && ErrorsShow {
handler(rw, r)
} else {
if !RecoverPanic {
// go back to panic
panic(err)
} else {
var stack string
Critical("Handler crashed with error", err)
for i := 1; ; i++ {
_, file, line, ok := runtime.Caller(i)
if !ok {
break
}
Critical(file, line)
if RunMode == "dev" {
stack = stack + fmt.Sprintln(file, line)
}
}
if RunMode == "dev" {
middleware.ShowErr(err, rw, r, stack)
}
}
}
}
}
}()
starttime := time.Now()
requestPath := r.URL.Path
var runrouter *controllerInfo
var findrouter bool
params := make(map[string]string)
w := &responseWriter{writer: rw}
w.Header().Set("Server", BeegoServerName)
context := &beecontext.Context{
ResponseWriter: w,
Request: r,
Input: beecontext.NewInput(r),
Output: beecontext.NewOutput(w),
}
context.Output.Context = context
context.Output.EnableGzip = EnableGzip
if context.Input.IsWebsocket() {
context.ResponseWriter = rw
context.Output = beecontext.NewOutput(rw)
}
if !inSlice(strings.ToLower(r.Method), HTTPMETHOD) {
http.Error(w, "Method Not Allowed", 405)
goto Admin
}
if p.enableFilter {
if l, ok := p.filters[BeforeRouter]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
//static file server
for prefix, staticDir := range StaticDir {
if r.URL.Path == "/favicon.ico" {
file := staticDir + r.URL.Path
http.ServeFile(w, r, file)
w.started = true
goto Admin
}
if strings.HasPrefix(r.URL.Path, prefix) {
file := staticDir + r.URL.Path[len(prefix):]
finfo, err := os.Stat(file)
if err != nil {
if RunMode == "dev" {
Warn(err)
}
http.NotFound(w, r)
goto Admin
}
//if the request is dir and DirectoryIndex is false then
if finfo.IsDir() && !DirectoryIndex {
middleware.Exception("403", rw, r, "403 Forbidden")
goto Admin
}
http.ServeFile(w, r, file)
w.started = true
goto Admin
}
}
// session init after static file
if SessionOn {
context.Input.CruSession = GlobalSessions.SessionStart(w, r)
}
if p.enableFilter {
if l, ok := p.filters[AfterStatic]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
if CopyRequestBody {
context.Input.Body()
}
//first find path from the fixrouters to Improve Performance
for _, route := range p.fixrouters {
n := len(requestPath)
if requestPath == route.pattern {
runrouter = route
findrouter = true
break
}
// pattern /admin url /admin 200 /admin/ 404
// pattern /admin/ url /admin 301 /admin/ 200
if requestPath[n-1] != '/' && len(route.pattern) == n+1 &&
route.pattern[n] == '/' && route.pattern[:n] == requestPath {
http.Redirect(w, r, requestPath+"/", 301)
goto Admin
}
}
//find regex's router
if !findrouter {
//find a matching Route
for _, route := range p.routers {
//check if Route pattern matches url
if !route.regex.MatchString(requestPath) {
continue
}
//get submatches (params)
matches := route.regex.FindStringSubmatch(requestPath)
//double check that the Route matches the URL pattern.
if len(matches[0]) != len(requestPath) {
continue
}
if len(route.params) > 0 {
//add url parameters to the query param map
values := r.URL.Query()
for i, match := range matches[1:] {
values.Add(route.params[i], match)
params[route.params[i]] = match
}
//reassemble query params and add to RawQuery
r.URL.RawQuery = url.Values(values).Encode()
}
runrouter = route
findrouter = true
break
}
}
context.Input.Param = params
if runrouter != nil {
if r.Method == "POST" {
r.ParseMultipartForm(MaxMemory)
}
//execute middleware filters
if p.enableFilter {
if l, ok := p.filters[BeforeExec]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
//Invoke the request handler
vc := reflect.New(runrouter.controllerType)
//call the controller init function
method := vc.MethodByName("Init")
in := make([]reflect.Value, 3)
in[0] = reflect.ValueOf(context)
in[1] = reflect.ValueOf(runrouter.controllerType.Name())
in[2] = reflect.ValueOf(vc.Interface())
method.Call(in)
//if XSRF is Enable then check cookie where there has any cookie in the request's cookie _csrf
if EnableXSRF {
in = make([]reflect.Value, 0)
method = vc.MethodByName("XsrfToken")
method.Call(in)
if r.Method == "POST" || r.Method == "DELETE" || r.Method == "PUT" ||
(r.Method == "POST" && (r.Form.Get("_method") == "delete" || r.Form.Get("_method") == "put")) {
method = vc.MethodByName("CheckXsrfCookie")
method.Call(in)
}
}
//call prepare function
in = make([]reflect.Value, 0)
method = vc.MethodByName("Prepare")
method.Call(in)
//if response has written,yes don't run next
if !w.started {
if r.Method == "GET" {
if runrouter.hasMethod {
if m, ok := runrouter.methods["get"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Get")
}
} else {
method = vc.MethodByName("Get")
}
method.Call(in)
} else if r.Method == "HEAD" {
if runrouter.hasMethod {
if m, ok := runrouter.methods["head"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Head")
}
} else {
method = vc.MethodByName("Head")
}
method.Call(in)
} else if r.Method == "DELETE" || (r.Method == "POST" && r.Form.Get("_method") == "delete") {
if runrouter.hasMethod {
if m, ok := runrouter.methods["delete"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Delete")
}
} else {
method = vc.MethodByName("Delete")
}
method.Call(in)
} else if r.Method == "PUT" || (r.Method == "POST" && r.Form.Get("_method") == "put") {
if runrouter.hasMethod {
if m, ok := runrouter.methods["put"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Put")
}
} else {
method = vc.MethodByName("Put")
}
method.Call(in)
} else if r.Method == "POST" {
if runrouter.hasMethod {
if m, ok := runrouter.methods["post"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Post")
}
} else {
method = vc.MethodByName("Post")
}
method.Call(in)
} else if r.Method == "PATCH" {
if runrouter.hasMethod {
if m, ok := runrouter.methods["patch"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Patch")
}
} else {
method = vc.MethodByName("Patch")
}
method.Call(in)
} else if r.Method == "OPTIONS" {
if runrouter.hasMethod {
if m, ok := runrouter.methods["options"]; ok {
method = vc.MethodByName(m)
} else if m, ok = runrouter.methods["*"]; ok {
method = vc.MethodByName(m)
} else {
method = vc.MethodByName("Options")
}
} else {
method = vc.MethodByName("Options")
}
method.Call(in)
}
gotofunc := vc.Elem().FieldByName("gotofunc").String()
if gotofunc != "" {
method = vc.MethodByName(gotofunc)
if method.IsValid() {
method.Call(in)
} else {
panic("gotofunc is exists:" + gotofunc)
}
}
if !w.started && !context.Input.IsWebsocket() {
if AutoRender {
method = vc.MethodByName("Render")
method.Call(in)
}
}
}
method = vc.MethodByName("Finish")
method.Call(in)
//execute middleware filters
if p.enableFilter {
if l, ok := p.filters[AfterExec]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
method = vc.MethodByName("Destructor")
method.Call(in)
}
//start autorouter
if p.enableAuto {
if !findrouter {
lastindex := strings.LastIndex(requestPath, "/")
lastsub := requestPath[lastindex+1:]
if subindex := strings.LastIndex(lastsub, "."); subindex != -1 {
context.Input.Param[":ext"] = lastsub[subindex+1:]
r.URL.Query().Add(":ext", lastsub[subindex+1:])
r.URL.RawQuery = r.URL.Query().Encode()
requestPath = requestPath[:len(requestPath)-len(lastsub[subindex:])]
}
for cName, methodmap := range p.autoRouter {
if strings.ToLower(requestPath) == "/"+cName {
http.Redirect(w, r, requestPath+"/", 301)
goto Admin
}
if strings.ToLower(requestPath) == "/"+cName+"/" {
requestPath = requestPath + "index"
}
if strings.HasPrefix(strings.ToLower(requestPath), "/"+cName+"/") {
for mName, controllerType := range methodmap {
if strings.ToLower(requestPath) == "/"+cName+"/"+strings.ToLower(mName) ||
(strings.HasPrefix(strings.ToLower(requestPath), "/"+cName+"/"+strings.ToLower(mName)) &&
requestPath[len("/"+cName+"/"+strings.ToLower(mName)):len("/"+cName+"/"+strings.ToLower(mName))+1] == "/") {
if r.Method == "POST" {
r.ParseMultipartForm(MaxMemory)
}
// set find
findrouter = true
//execute middleware filters
if p.enableFilter {
if l, ok := p.filters[BeforeExec]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
//parse params
otherurl := requestPath[len("/"+cName+"/"+strings.ToLower(mName)):]
if len(otherurl) > 1 {
plist := strings.Split(otherurl, "/")
for k, v := range plist[1:] {
params[strconv.Itoa(k)] = v
}
}
//Invoke the request handler
vc := reflect.New(controllerType)
//call the controller init function
init := vc.MethodByName("Init")
in := make([]reflect.Value, 3)
in[0] = reflect.ValueOf(context)
in[1] = reflect.ValueOf(controllerType.Name())
in[2] = reflect.ValueOf(vc.Interface())
init.Call(in)
//call prepare function
in = make([]reflect.Value, 0)
method := vc.MethodByName("Prepare")
method.Call(in)
method = vc.MethodByName(mName)
method.Call(in)
//if XSRF is Enable then check cookie where there has any cookie in the request's cookie _csrf
if EnableXSRF {
method = vc.MethodByName("XsrfToken")
method.Call(in)
if r.Method == "POST" || r.Method == "DELETE" || r.Method == "PUT" ||
(r.Method == "POST" && (r.Form.Get("_method") == "delete" || r.Form.Get("_method") == "put")) {
method = vc.MethodByName("CheckXsrfCookie")
method.Call(in)
}
}
if !w.started && !context.Input.IsWebsocket() {
if AutoRender {
method = vc.MethodByName("Render")
method.Call(in)
}
}
method = vc.MethodByName("Finish")
method.Call(in)
//execute middleware filters
if p.enableFilter {
if l, ok := p.filters[AfterExec]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
goto Admin
}
}
}
}
}
method = vc.MethodByName("Destructor")
method.Call(in)
goto Admin
}
}
}
}
}
}
//if no matches to url, throw a not found exception
if !findrouter {
middleware.Exception("404", rw, r, "")
}
Admin:
if p.enableFilter {
if l, ok := p.filters[FinishRouter]; ok {
for _, filterR := range l {
if filterR.ValidRouter(r.URL.Path) {
filterR.filterFunc(context)
if w.started {
break
}
}
}
}
}
//admin module record QPS
if EnableAdmin {
timeend := time.Since(starttime)
if FilterMonitorFunc(r.Method, requestPath, timeend) {
if runrouter != nil {
go toolbox.StatisticsMap.AddStatistics(r.Method, requestPath, runrouter.controllerType.Name(), timeend)
} else {
go toolbox.StatisticsMap.AddStatistics(r.Method, requestPath, "", timeend)
}
}
}
}
//responseWriter is a wrapper for the http.ResponseWriter
//started set to true if response was written to then don't execute other handler
type responseWriter struct {
writer http.ResponseWriter
started bool
status int
}
// Header returns the header map that will be sent by WriteHeader.
func (w *responseWriter) Header() http.Header {
return w.writer.Header()
}
// Write writes the data to the connection as part of an HTTP reply,
// and sets `started` to true
func (w *responseWriter) Write(p []byte) (int, error) {
w.started = true
return w.writer.Write(p)
}
// WriteHeader sends an HTTP response header with status code,
// and sets `started` to true
func (w *responseWriter) WriteHeader(code int) {
w.status = code
w.started = true
w.writer.WriteHeader(code)
}