gitea/modules/middleware/render.go
2014-05-25 20:11:25 -04:00

282 lines
5.7 KiB
Go

// Copyright 2014 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
// foked from https://github.com/martini-contrib/render/blob/master/render.go
package middleware
import (
"bytes"
"encoding/json"
"fmt"
"html/template"
"io"
"io/ioutil"
"net/http"
"os"
"path/filepath"
"time"
"github.com/go-martini/martini"
"github.com/gogits/gogs/modules/base"
)
const (
ContentType = "Content-Type"
ContentLength = "Content-Length"
ContentJSON = "application/json"
ContentHTML = "text/html"
ContentXHTML = "application/xhtml+xml"
defaultCharset = "UTF-8"
)
var helperFuncs = template.FuncMap{
"yield": func() (string, error) {
return "", fmt.Errorf("yield called with no layout defined")
},
}
type Delims struct {
Left string
Right string
}
type RenderOptions struct {
Directory string
Layout string
Extensions []string
Funcs []template.FuncMap
Delims Delims
Charset string
IndentJSON bool
HTMLContentType string
}
type HTMLOptions struct {
Layout string
}
func Renderer(options ...RenderOptions) martini.Handler {
opt := prepareOptions(options)
cs := prepareCharset(opt.Charset)
t := compile(opt)
return func(res http.ResponseWriter, req *http.Request, c martini.Context) {
var tc *template.Template
if martini.Env == martini.Dev {
tc = compile(opt)
} else {
tc, _ = t.Clone()
}
rd := &Render{res, req, tc, opt, cs, base.TmplData{}, time.Time{}}
rd.Data["TmplLoadTimes"] = func() string {
if rd.startTime.IsZero() {
return ""
}
return fmt.Sprint(time.Since(rd.startTime).Nanoseconds()/1e6) + "ms"
}
c.Map(rd.Data)
c.Map(rd)
}
}
func prepareCharset(charset string) string {
if len(charset) != 0 {
return "; charset=" + charset
}
return "; charset=" + defaultCharset
}
func prepareOptions(options []RenderOptions) RenderOptions {
var opt RenderOptions
if len(options) > 0 {
opt = options[0]
}
if len(opt.Directory) == 0 {
opt.Directory = "templates"
}
if len(opt.Extensions) == 0 {
opt.Extensions = []string{".tmpl"}
}
if len(opt.HTMLContentType) == 0 {
opt.HTMLContentType = ContentHTML
}
return opt
}
func compile(options RenderOptions) *template.Template {
dir := options.Directory
t := template.New(dir)
t.Delims(options.Delims.Left, options.Delims.Right)
template.Must(t.Parse("Martini"))
filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
r, err := filepath.Rel(dir, path)
if err != nil {
return err
}
ext := filepath.Ext(r)
for _, extension := range options.Extensions {
if ext == extension {
buf, err := ioutil.ReadFile(path)
if err != nil {
panic(err)
}
name := (r[0 : len(r)-len(ext)])
tmpl := t.New(filepath.ToSlash(name))
for _, funcs := range options.Funcs {
tmpl = tmpl.Funcs(funcs)
}
template.Must(tmpl.Funcs(helperFuncs).Parse(string(buf)))
break
}
}
return nil
})
return t
}
type Render struct {
http.ResponseWriter
req *http.Request
t *template.Template
opt RenderOptions
compiledCharset string
Data base.TmplData
startTime time.Time
}
func (r *Render) JSON(status int, v interface{}) {
var result []byte
var err error
if r.opt.IndentJSON {
result, err = json.MarshalIndent(v, "", " ")
} else {
result, err = json.Marshal(v)
}
if err != nil {
http.Error(r, err.Error(), 500)
return
}
r.Header().Set(ContentType, ContentJSON+r.compiledCharset)
r.WriteHeader(status)
r.Write(result)
}
func (r *Render) JSONString(v interface{}) (string, error) {
var result []byte
var err error
if r.opt.IndentJSON {
result, err = json.MarshalIndent(v, "", " ")
} else {
result, err = json.Marshal(v)
}
if err != nil {
return "", err
}
return string(result), nil
}
func (r *Render) renderBytes(name string, binding interface{}, htmlOpt ...HTMLOptions) (*bytes.Buffer, error) {
opt := r.prepareHTMLOptions(htmlOpt)
if len(opt.Layout) > 0 {
r.addYield(name, binding)
name = opt.Layout
}
out, err := r.execute(name, binding)
if err != nil {
return nil, err
}
return out, nil
}
func (r *Render) HTML(status int, name string, binding interface{}, htmlOpt ...HTMLOptions) {
r.startTime = time.Now()
out, err := r.renderBytes(name, binding, htmlOpt...)
if err != nil {
http.Error(r, err.Error(), http.StatusInternalServerError)
return
}
r.Header().Set(ContentType, r.opt.HTMLContentType+r.compiledCharset)
r.WriteHeader(status)
io.Copy(r, out)
}
func (r *Render) HTMLString(name string, binding interface{}, htmlOpt ...HTMLOptions) (string, error) {
if out, err := r.renderBytes(name, binding, htmlOpt...); err != nil {
return "", err
} else {
return out.String(), nil
}
}
func (r *Render) Error(status int, message ...string) {
r.WriteHeader(status)
if len(message) > 0 {
r.Write([]byte(message[0]))
}
}
func (r *Render) Redirect(location string, status ...int) {
code := http.StatusFound
if len(status) == 1 {
code = status[0]
}
http.Redirect(r, r.req, location, code)
}
func (r *Render) Template() *template.Template {
return r.t
}
func (r *Render) execute(name string, binding interface{}) (*bytes.Buffer, error) {
buf := new(bytes.Buffer)
return buf, r.t.ExecuteTemplate(buf, name, binding)
}
func (r *Render) addYield(name string, binding interface{}) {
funcs := template.FuncMap{
"yield": func() (template.HTML, error) {
buf, err := r.execute(name, binding)
return template.HTML(buf.String()), err
},
}
r.t.Funcs(funcs)
}
func (r *Render) prepareHTMLOptions(htmlOpt []HTMLOptions) HTMLOptions {
if len(htmlOpt) > 0 {
return htmlOpt[0]
}
return HTMLOptions{
Layout: r.opt.Layout,
}
}