forked from kataras/iris
/
html.go
381 lines (333 loc) · 10.8 KB
/
html.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
// Copyright 2017 Gerasimos Maropoulos, ΓΜ. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package view
import (
"bytes"
"fmt"
"html/template"
"io"
"io/ioutil"
"os"
"path/filepath"
"strings"
"sync"
)
type (
// HTMLEngine contains the html view engine structure.
HTMLEngine struct {
// files configuration
directory string
extension string
assetFn func(name string) ([]byte, error) // for embedded, in combination with directory & extension
namesFn func() []string // for embedded, in combination with directory & extension
reload bool // if true, each time the ExecuteWriter is called the templates will be reloaded.
// parser configuration
left string
right string
layout string
rmu sync.RWMutex // locks for layoutFuncs and funcs
layoutFuncs map[string]interface{}
funcs map[string]interface{}
//
middleware func(name string, contents string) (string, error)
mu sync.Mutex // locks for template files loader
Templates *template.Template
//
}
)
var _ Engine = &HTMLEngine{}
var emptyFuncs = template.FuncMap{
"yield": func() (string, error) {
return "", fmt.Errorf("yield was called, yet no layout defined")
},
"partial": func() (string, error) {
return "", fmt.Errorf("block was called, yet no layout defined")
},
"partial_r": func() (string, error) {
return "", fmt.Errorf("block was called, yet no layout defined")
},
"current": func() (string, error) {
return "", nil
}, "render": func() (string, error) {
return "", nil
},
}
// HTML creates and returns a new html view engine.
// The html engine used like the "html/template" standard go package
// but with a lot of extra features.
func HTML(directory, extension string) *HTMLEngine {
s := &HTMLEngine{
directory: directory,
extension: extension,
assetFn: nil,
namesFn: nil,
reload: false,
left: "{{",
right: "}}",
layout: "",
layoutFuncs: make(map[string]interface{}, 0),
funcs: make(map[string]interface{}, 0),
}
return s
}
// Ext returns the file extension which this view engine is responsible to render.
func (s *HTMLEngine) Ext() string {
return s.extension
}
// Binary optionally, use it when template files are distributed
// inside the app executable (.go generated files).
//
// The assetFn and namesFn can come from the go-bindata library.
func (s *HTMLEngine) Binary(assetFn func(name string) ([]byte, error), namesFn func() []string) *HTMLEngine {
s.assetFn, s.namesFn = assetFn, namesFn
return s
}
// Reload if setted to true the templates are reloading on each render,
// use it when you're in development and you're boring of restarting
// the whole app when you edit a template file.
func (s *HTMLEngine) Reload(developmentMode bool) *HTMLEngine {
s.reload = developmentMode
return s
}
// Delims sets the action delimiters to the specified strings, to be used in
// subsequent calls to Parse, ParseFiles, or ParseGlob. Nested template
// definitions will inherit the settings. An empty delimiter stands for the
// corresponding default: {{ or }}.
func (s *HTMLEngine) Delims(left, right string) *HTMLEngine {
s.left, s.right = left, right
return s
}
// Layout sets the layout template file which inside should use
// the {{ yield }} func to yield the main template file
// and optionally {{partial/partial_r/render}} to render other template files like headers and footers
//
// The 'tmplLayoutFile' is a relative path of the templates base directory,
// for the template file with its extension.
//
// Example: HTML("./templates", ".html").Layout("layouts/mainLayout.html")
// // mainLayout.html is inside: "./templates/layouts/".
//
// Note: Layout can be changed for a specific call
// action with the option: "layout" on the Iris' context.Render function.
func (s *HTMLEngine) Layout(layoutFile string) *HTMLEngine {
s.layout = layoutFile
return s
}
// AddLayoutFunc adds the function to the template's layout-only function map.
// It is legal to overwrite elements of the default layout actions:
// - yield func() (template.HTML, error)
// - current func() (string, error)
// - partial func(partialName string) (template.HTML, error)
// - partial_r func(partialName string) (template.HTML, error)
// - render func(fullPartialName string) (template.HTML, error).
func (s *HTMLEngine) AddLayoutFunc(funcName string, funcBody interface{}) *HTMLEngine {
s.rmu.Lock()
s.layoutFuncs[funcName] = funcBody
s.rmu.Unlock()
return s
}
// AddFunc adds the function to the template's function map.
// It is legal to overwrite elements of the default actions:
// - url func(routeName string, args ...string) string
// - urlpath func(routeName string, args ...string) string
// - render func(fullPartialName string) (template.HTML, error).
func (s *HTMLEngine) AddFunc(funcName string, funcBody interface{}) {
s.rmu.Lock()
s.funcs[funcName] = funcBody
s.rmu.Unlock()
}
// Load parses the templates to the engine.
// It's alos responsible to add the necessary global functions.
//
// Returns an error if something bad happens, user is responsible to catch it.
func (s *HTMLEngine) Load() error {
if s.assetFn != nil && s.namesFn != nil {
// embedded
return s.loadAssets()
}
// load from directory, make the dir absolute here too.
dir, err := filepath.Abs(s.directory)
if err != nil {
return err
}
// change the directory field configuration, load happens after directory has been setted, so we will not have any problems here.
s.directory = dir
return s.loadDirectory()
}
// loadDirectory builds the templates from directory.
func (s *HTMLEngine) loadDirectory() error {
dir, extension := s.directory, s.extension
var templateErr error
s.Templates = template.New(dir)
s.Templates.Delims(s.left, s.right)
filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
if info == nil || info.IsDir() {
} else {
rel, err := filepath.Rel(dir, path)
if err != nil {
templateErr = err
return err
}
ext := filepath.Ext(path)
if ext == extension {
buf, err := ioutil.ReadFile(path)
if err != nil {
templateErr = err
return err
}
contents := string(buf)
if err == nil {
name := filepath.ToSlash(rel)
tmpl := s.Templates.New(name)
if s.middleware != nil {
contents, err = s.middleware(name, contents)
}
if err != nil {
templateErr = err
return err
}
s.mu.Lock()
// Add our funcmaps.
if s.funcs != nil {
tmpl.Funcs(s.funcs)
}
tmpl.Funcs(emptyFuncs).Parse(contents)
s.mu.Unlock()
}
}
}
return nil
})
return templateErr
}
// loadAssets loads the templates by binary (go-bindata for embedded).
func (s *HTMLEngine) loadAssets() error {
virtualDirectory, virtualExtension := s.directory, s.extension
assetFn, namesFn := s.assetFn, s.namesFn
var templateErr error
s.Templates = template.New(virtualDirectory)
s.Templates.Delims(s.left, s.right)
names := namesFn()
if len(virtualDirectory) > 0 {
if virtualDirectory[0] == '.' { // first check for .wrong
virtualDirectory = virtualDirectory[1:]
}
if virtualDirectory[0] == '/' || virtualDirectory[0] == os.PathSeparator { // second check for /something, (or ./something if we had dot on 0 it will be removed
virtualDirectory = virtualDirectory[1:]
}
}
for _, path := range names {
if !strings.HasPrefix(path, virtualDirectory) {
continue
}
ext := filepath.Ext(path)
if ext == virtualExtension {
rel, err := filepath.Rel(virtualDirectory, path)
if err != nil {
templateErr = err
return err
}
buf, err := assetFn(path)
if err != nil {
templateErr = err
return err
}
contents := string(buf)
name := filepath.ToSlash(rel)
tmpl := s.Templates.New(name)
if s.middleware != nil {
contents, err = s.middleware(name, contents)
}
if err != nil {
templateErr = err
return err
}
// Add our funcmaps.
if s.funcs != nil {
tmpl.Funcs(s.funcs)
}
tmpl.Funcs(emptyFuncs).Parse(contents)
}
}
return templateErr
}
func (s *HTMLEngine) executeTemplateBuf(name string, binding interface{}) (*bytes.Buffer, error) {
buf := new(bytes.Buffer)
err := s.Templates.ExecuteTemplate(buf, name, binding)
return buf, err
}
func (s *HTMLEngine) layoutFuncsFor(name string, binding interface{}) {
funcs := template.FuncMap{
"yield": func() (template.HTML, error) {
buf, err := s.executeTemplateBuf(name, binding)
// Return safe HTML here since we are rendering our own template.
return template.HTML(buf.String()), err
},
"current": func() (string, error) {
return name, nil
},
"partial": func(partialName string) (template.HTML, error) {
fullPartialName := fmt.Sprintf("%s-%s", partialName, name)
if s.Templates.Lookup(fullPartialName) != nil {
buf, err := s.executeTemplateBuf(fullPartialName, binding)
return template.HTML(buf.String()), err
}
return "", nil
},
//partial related to current page,
//it would be easier for adding pages' style/script inline
//for example when using partial_r '.script' in layout.html
//templates/users/index.html would load templates/users/index.script.html
"partial_r": func(partialName string) (template.HTML, error) {
ext := filepath.Ext(name)
root := name[:len(name)-len(ext)]
fullPartialName := fmt.Sprintf("%s%s%s", root, partialName, ext)
if s.Templates.Lookup(fullPartialName) != nil {
buf, err := s.executeTemplateBuf(fullPartialName, binding)
return template.HTML(buf.String()), err
}
return "", nil
},
"render": func(fullPartialName string) (template.HTML, error) {
buf, err := s.executeTemplateBuf(fullPartialName, binding)
return template.HTML(buf.String()), err
},
}
s.rmu.RLock()
for k, v := range s.layoutFuncs {
funcs[k] = v
}
s.rmu.RUnlock()
if tpl := s.Templates.Lookup(name); tpl != nil {
tpl.Funcs(funcs)
}
}
func (s *HTMLEngine) runtimeFuncsFor(name string, binding interface{}) {
funcs := template.FuncMap{
"render": func(fullPartialName string) (template.HTML, error) {
buf, err := s.executeTemplateBuf(fullPartialName, binding)
return template.HTML(buf.String()), err
},
}
if tpl := s.Templates.Lookup(name); tpl != nil {
tpl.Funcs(funcs)
}
}
// ExecuteWriter executes a template and writes its result to the w writer.
func (s *HTMLEngine) ExecuteWriter(w io.Writer, name string, layout string, bindingData interface{}) error {
// reload the templates if reload configuration field is true
if s.reload {
if err := s.Load(); err != nil {
return err
}
}
layout = getLayout(layout, s.layout)
if layout != "" {
s.layoutFuncsFor(name, bindingData)
name = layout
} else {
s.runtimeFuncsFor(name, bindingData)
}
return s.Templates.ExecuteTemplate(w, name, bindingData)
}