-
Notifications
You must be signed in to change notification settings - Fork 10
/
codeigniter.html
566 lines (464 loc) · 16.6 KB
/
codeigniter.html
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
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
<!DOCTYPE html>
<!--[if lt IE 7]> <html class="no-js lt-ie9 lt-ie8 lt-ie7"> <![endif]-->
<!--[if IE 7]> <html class="no-js lt-ie9 lt-ie8"> <![endif]-->
<!--[if IE 8]> <html class="no-js lt-ie9"> <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js"> <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title></title>
<meta name="description" content="">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Place favicon.ico and apple-touch-icon.png in the root directory -->
<link rel="stylesheet" href="css/normalize.css">
<link rel="stylesheet" href="css/main.css">
<script src="js/vendor/modernizr-2.6.2.min.js"></script>
<link rel="stylesheet" href="css/bootstrap.css">
<link rel="stylesheet" href="css/shCore.css">
<link rel="stylesheet" href="css/shThemeDefault.css">
<script src="js/shCore.js"></script>
<script src="js/shBrushPhp.js"></script>
</head>
<body>
<!--[if lt IE 7]>
<p class="browsehappy">You are using an <strong>outdated</strong> browser. Please <a href="https://browsehappy.com/">upgrade your browser</a> to improve your experience.</p>
<![endif]-->
<!-- Add your site or application content here -->
<div class='alert alert-success'>
我們開始分析Codeigniter.php。<br />
</div>
<pre class="brush: php">
/**
* CodeIgniter
*
* An open source application development framework for PHP 5.1.6 or newer
*
* @package CodeIgniter
* @author ExpressionEngine Dev Team
* @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
* @license https://codeigniter.com/user_guide/license.html
* @link https://codeigniter.com
* @since Version 1.0
* @filesource
*/
// ------------------------------------------------------------------------
/**
* System Initialization File
*
* Loads the base classes and executes the request.
*
* @package CodeIgniter
* @subpackage codeigniter
* @category Front-controller
* @author ExpressionEngine Dev Team
* @link https://codeigniter.com/user_guide/
*/
/**
* CodeIgniter Version
*
* @var string
*
*/
define('CI_VERSION', '2.1.4');
/**
* CodeIgniter Branch (Core = TRUE, Reactor = FALSE)
*
* @var boolean
*
*/
define('CI_CORE', FALSE);
/*
* ------------------------------------------------------
* Load the global functions
* ------------------------------------------------------
*/
require(BASEPATH.'core/Common.php');
</pre>
<div class='alert alert-success'>
首先載入整個CI框架會用到的一些全域函式。<br />
<a href='common.html'>core/common.php</a>
</div>
<div class='alert alert-danger'>
這些全域函式讓CI各個元件能整合在一起，卻也導致各元件彼此不可獨立。<br />
（不像Laravel的Eloquent ORM就可以獨立出來使用。）<br />
有沒有辦法避免彼此相依這件事呢？
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Load the framework constants
* ------------------------------------------------------
*/
if (defined('ENVIRONMENT') AND file_exists(APPPATH.'config/'.ENVIRONMENT.'/constants.php'))
{
require(APPPATH.'config/'.ENVIRONMENT.'/constants.php');
}
else
{
require(APPPATH.'config/constants.php');
}
</pre>
<div class='alert alert-success'>
這個地方載入了不同環境下的常數。<br/>
注意此處的彈性：可以全部環境共用共一份檔案。
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Define a custom error handler so we can log PHP errors
* ------------------------------------------------------
*/
set_error_handler('_exception_handler');
if ( ! is_php('5.3'))
{
@set_magic_quotes_runtime(0); // Kill magic quotes
}
/*
* ------------------------------------------------------
* Set the subclass_prefix
* ------------------------------------------------------
*
* Normally the "subclass_prefix" is set in the config file.
* The subclass prefix allows CI to know if a core class is
* being extended via a library in the local application
* "libraries" folder. Since CI allows config items to be
* overriden via data set in the main index. php file,
* before proceeding we need to know if a subclass_prefix
* override exists. If so, we will set this value now,
* before any classes are loaded
* Note: Since the config file data is cached it doesn't
* hurt to load it here.
*/
if (isset($assign_to_config['subclass_prefix']) AND $assign_to_config['subclass_prefix'] != '')
{
get_config(array('subclass_prefix' => $assign_to_config['subclass_prefix']));
}
/*
* ------------------------------------------------------
* Set a liberal script execution time limit
* ------------------------------------------------------
*/
if (function_exists("set_time_limit") == TRUE AND @ini_get("safe_mode") == 0)
{
@set_time_limit(300);
}
/*
* ------------------------------------------------------
* Start the timer... tick tock tick tock...
* ------------------------------------------------------
*/
$BM =& load_class('Benchmark', 'core');
$BM->mark('total_execution_time_start');
$BM->mark('loading_time:_base_classes_start');
/*
* ------------------------------------------------------
* Instantiate the hooks class
* ------------------------------------------------------
*/
$EXT =& load_class('Hooks', 'core');
/*
* ------------------------------------------------------
* Is there a "pre_system" hook?
* ------------------------------------------------------
*/
$EXT->_call_hook('pre_system');
</pre>
<div class='alert alert-success'>
載入Hook類別，讓開發者可以在不同時間點執行某些任務，例如：CI載入前、controller執行前、CI執行完畢之後...等等。<br />
Hook類別是提供進階開發者使用的，它的存在主要是為了支援<a href='https://zh.wikipedia.org/wiki/%E9%9D%A2%E5%90%91%E4%BE%A7%E9%9D%A2%E7%9A%84%E7%A8%8B%E5%BA%8F%E8%AE%BE%E8%AE%A1' target='_blank'>Aspect-Oriented Programming</a>開發方法。<br/>
關於在CI內進行AOP開發，我推薦一篇很棒的文章：<a href='https://www.sitepoint.com/explore-aspect-oriented-programming-with-codeigniter-1/'>Explore Aspect Oriented Programming with CodeIgniter</a>
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Instantiate the config class
* ------------------------------------------------------
*/
$CFG =& load_class('Config', 'core');
// Do we have any manually set config items in the index.php file?
if (isset($assign_to_config))
{
$CFG->_assign_to_config($assign_to_config);
}
/*
* ------------------------------------------------------
* Instantiate the UTF-8 class
* ------------------------------------------------------
*
* Note: Order here is rather important as the UTF-8
* class needs to be used very early on, but it cannot
* properly determine if UTf-8 can be supported until
* after the Config class is instantiated.
*
*/
$UNI =& load_class('Utf8', 'core');
/*
* ------------------------------------------------------
* Instantiate the URI class
* ------------------------------------------------------
*/
$URI =& load_class('URI', 'core');
/*
* ------------------------------------------------------
* Instantiate the routing class and set the routing
* ------------------------------------------------------
*/
$RTR =& load_class('Router', 'core');
$RTR->_set_routing();
// Set any routing overrides that may exist in the main index file
if (isset($routing))
{
$RTR->_set_overrides($routing);
}
</pre>
<div class='alert alert-success'>
這邊載入Router類別，去分析網址以做出對應動作。<br />
參考：<a href='router.html'>找到該走的路：core/router.php</a>
</div>
<div class='alert alert-danger'>
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Instantiate the output class
* ------------------------------------------------------
*/
$OUT =& load_class('Output', 'core');
</pre>
<div class='alert alert-success'>
載入Output類別。它在這份檔案只做兩件事：<br/>
1. 有cache時，負責把cache頁面丟給使用者。<br />
2. 沒cache時，負責產出最後ouput的任務。<br />
請參見：<a href='output.html'>回傳最後結果：core/Output.php</a>
</div>
<div class='alert alert-danger'>
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Is there a valid cache file? If so, we're done...
* ------------------------------------------------------
*/
if ($EXT->_call_hook('cache_override') === FALSE)
{
if ($OUT->_display_cache($CFG, $URI) == TRUE)
{
exit;
}
}
/*
* -----------------------------------------------------
* Load the security class for xss and csrf support
* -----------------------------------------------------
*/
$SEC =& load_class('Security', 'core');
</pre>
<div class='alert alert-success'>
</div>
<div class='alert alert-danger'>
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Load the Input class and sanitize globals
* ------------------------------------------------------
*/
$IN =& load_class('Input', 'core');
</pre>
<div class='alert alert-success'>
讀取Input類別。在這邊執行建構式的同時，也對PHP的$_GET等變數進行了「消毒」。<br/>
參見<a href='input.html'>資訊安全護城河：core/Input.php</a>
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Load the Language class
* ------------------------------------------------------
*/
$LANG =& load_class('Lang', 'core');
/*
* ------------------------------------------------------
* Load the app controller and local controller
* ------------------------------------------------------
*
*/
// Load the base controller class
require BASEPATH.'core/Controller.php';
function &get_instance()
{
return CI_Controller::get_instance();
}
if (file_exists(APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php'))
{
require APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php';
}
// Load the local application controller
// Note: The Router class automatically validates the controller path using the router->_validate_request().
// If this include fails it means that the default controller in the Routes.php file is not resolving to something valid.
if ( ! file_exists(APPPATH.'controllers/'.$RTR->fetch_directory().$RTR->fetch_class().'.php'))
{
show_error('Unable to load your default controller. Please make sure the controller specified in your Routes.php file is valid.');
}
include(APPPATH.'controllers/'.$RTR->fetch_directory().$RTR->fetch_class().'.php');
// Set a mark point for benchmarking
$BM->mark('loading_time:_base_classes_end');
</pre>
<div class='alert alert-success'>
載入controller類別，接著定義一個全域函數，可以接觸ci本體物件。<br/>
在開發application時，在model、controller等地方會寫到的$this就是繼承這個本體物件。<br/>
甚至在撰寫library時，常常為了使用ci本身的helper、model等功能，寫出 $this->ci =& get_instance() 這樣的程式碼。<br/>
參見：<a href='controller.html'>組裝在一起：core/Controller.php</a>
</div>
<div class='alert alert-danger'>
在core資料夾的類別，幾乎都是用load_class全域函數載入，這邊卻是用require與include。<br/>
載入各個類別的機制顯得很混亂。
</div>
<pre class="brush: php">
/*
* ------------------------------------------------------
* Security check
* ------------------------------------------------------
*
* None of the functions in the app controller or the
* loader class can be called via the URI, nor can
* controller functions that begin with an underscore
*/
$class = $RTR->fetch_class();
$method = $RTR->fetch_method();
if ( ! class_exists($class)
OR strncmp($method, '_', 1) == 0
OR in_array(strtolower($method), array_map('strtolower', get_class_methods('CI_Controller')))
)
{
if ( ! empty($RTR->routes['404_override']))
{
$x = explode('/', $RTR->routes['404_override']);
$class = $x[0];
$method = (isset($x[1]) ? $x[1] : 'index');
if ( ! class_exists($class))
{
if ( ! file_exists(APPPATH.'controllers/'.$class.'.php'))
{
show_404("{$class}/{$method}");
}
include_once(APPPATH.'controllers/'.$class.'.php');
}
}
else
{
show_404("{$class}/{$method}");
}
}
/*
* ------------------------------------------------------
* Is there a "pre_controller" hook?
* ------------------------------------------------------
*/
$EXT->_call_hook('pre_controller');
/*
* ------------------------------------------------------
* Instantiate the requested controller
* ------------------------------------------------------
*/
// Mark a start point so we can benchmark the controller
$BM->mark('controller_execution_time_( '.$class.' / '.$method.' )_start');
$CI = new $class();
/*
* ------------------------------------------------------
* Is there a "post_controller_constructor" hook?
* ------------------------------------------------------
*/
$EXT->_call_hook('post_controller_constructor');
/*
* ------------------------------------------------------
* Call the requested method
* ------------------------------------------------------
*/
// Is there a "remap" function? If so, we call it instead
if (method_exists($CI, '_remap'))
{
$CI->_remap($method, array_slice($URI->rsegments, 2));
}
else
{
// is_callable() returns TRUE on some versions of PHP 5 for private and protected
// methods, so we'll use this workaround for consistent behavior
if ( ! in_array(strtolower($method), array_map('strtolower', get_class_methods($CI))))
{
// Check and see if we are using a 404 override and use it.
if ( ! empty($RTR->routes['404_override']))
{
$x = explode('/', $RTR->routes['404_override']);
$class = $x[0];
$method = (isset($x[1]) ? $x[1] : 'index');
if ( ! class_exists($class))
{
if ( ! file_exists(APPPATH.'controllers/'.$class.'.php'))
{
show_404("{$class}/{$method}");
}
include_once(APPPATH.'controllers/'.$class.'.php');
unset($CI);
$CI = new $class();
}
}
else
{
show_404("{$class}/{$method}");
}
}
// Call the requested method.
// Any URI segments present (besides the class/function) will be passed to the method for convenience
call_user_func_array(array(&$CI, $method), array_slice($URI->rsegments, 2));
}
// Mark a benchmark end point
$BM->mark('controller_execution_time_( '.$class.' / '.$method.' )_end');
/*
* ------------------------------------------------------
* Is there a "post_controller" hook?
* ------------------------------------------------------
*/
$EXT->_call_hook('post_controller');
/*
* ------------------------------------------------------
* Send the final rendered output to the browser
* ------------------------------------------------------
*/
if ($EXT->_call_hook('display_override') === FALSE)
{
$OUT->_display();
}
/*
* ------------------------------------------------------
* Is there a "post_system" hook?
* ------------------------------------------------------
*/
$EXT->_call_hook('post_system');
/*
* ------------------------------------------------------
* Close the DB connection if one exists
* ------------------------------------------------------
*/
if (class_exists('CI_DB') AND isset($CI->db))
{
$CI->db->close();
}
/* End of file CodeIgniter.php */
/* Location: ./system/core/CodeIgniter.php */
</pre>
<!-- Finally, to actually run the highlighter, you need to include this JS on your page -->
<script type="text/javascript">
SyntaxHighlighter.all()
</script>
</body>
<style>
body{
width: 960px;
margin: 0 auto;
background-color: #444;
}
.alert{
line-height: 2;
}
</style>
</html>