/
Container.php
executable file
·505 lines (441 loc) · 11.9 KB
/
Container.php
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
<?php namespace Illuminate\Container; use Closure, ArrayAccess, ReflectionParameter;
class BindingResolutionException extends \Exception {}
class Container implements ArrayAccess {
/**
* The container's bindings.
*
* @var array
*/
protected $bindings = array();
/**
* The container's shared instances.
*
* @var array
*/
protected $instances = array();
/**
* The registered type aliases.
*
* @var array
*/
protected $aliases = array();
/**
* All of the registered resolving callbacks.
*
* @var array
*/
protected $resolvingCallbacks = array();
/**
* Determine if the given abstract type has been bound.
*
* @param string $abstract
* @return bool
*/
public function bound($abstract)
{
return isset($this[$abstract]) or isset($this->instances[$abstract]);
}
/**
* Register a binding with the container.
*
* @param string $abstract
* @param Closure|string|null $concrete
* @param bool $shared
* @return void
*/
public function bind($abstract, $concrete = null, $shared = false)
{
// If the given type is actually an array, we'll assume an alias is being
// defined and will grab the real abstract class name and register the
// alias with the container so it can be used as a short-cut for it.
if (is_array($abstract))
{
list($abstract, $alias) = $this->extractAlias($abstract);
$this->alias($abstract, $alias);
}
// If no concrete type was given, we will simply set the concrete type to
// the abstract. This allows concrete types to be registered as shared
// without being made state their classes in both of the parameters.
unset($this->instances[$abstract]);
if (is_null($concrete))
{
$concrete = $abstract;
}
// If the factory is not a Closure, it means it is just a class name that
// is bound into the container to an abstract type and we'll just wrap
// it up in a Closure to make things more convenient when extending.
if ( ! $concrete instanceof Closure)
{
$concrete = function($c) use ($abstract, $concrete)
{
$method = ($abstract == $concrete) ? 'build' : 'make';
return $c->$method($concrete);
};
}
$this->bindings[$abstract] = compact('concrete', 'shared');
}
/**
* Register a binding if it hasn't already been registered.
*
* @param string $abstract
* @param Closure|string|null $concrete
* @param bool $shared
* @return bool
*/
public function bindIf($abstract, $concrete = null, $shared = false)
{
if ( ! $this->bound($abstract))
{
$this->bind($abstract, $concrete, $shared);
}
}
/**
* Register a shared binding in the container.
*
* @param string $abstract
* @param Closure|string|null $concrete
* @return void
*/
public function singleton($abstract, $concrete = null)
{
return $this->bind($abstract, $concrete, true);
}
/**
* Wrap a Closure such that it is shared.
*
* @param Closure $closure
* @return Closure
*/
public function share(Closure $closure)
{
return function($container) use ($closure)
{
// We'll simply declare a static variable within the Closures and if
// it has not been set we'll execute the given Closure to resolve
// the value and return it back to the consumers of the method.
static $object;
if (is_null($object))
{
$object = $closure($container);
}
return $object;
};
}
/**
* "Extend" an abstract type in the container.
*
* @param string $abstract
* @param Closure $closure
* @return void
*/
public function extend($abstract, Closure $closure)
{
if ( ! isset($this->bindings[$abstract]))
{
throw new \InvalidArgumentException("Type {$abstract} is not bound.");
}
// To "extend" a binding, we will grab the old "resolver" Closure and pass it
// into a new one. The old resolver will be called first and the result is
// handed off to the "new" resolver, along with this container instance.
$resolver = $this->bindings[$abstract]['concrete'];
$this->bind($abstract, function($container) use ($resolver, $closure)
{
return $closure($resolver($container), $container);
}, $this->isShared($abstract));
}
/**
* Register an existing instance as shared in the container.
*
* @param string $abstract
* @param mixed $instance
* @return void
*/
public function instance($abstract, $instance)
{
if (is_array($abstract))
{
list($abstract, $alias) = $this->extractAlias($abstract);
$this->alias($abstract, $alias);
}
$this->instances[$abstract] = $instance;
}
/**
* Alias a type to a shorter name.
*
* @param string $abstract
* @param string $alias
* @return void
*/
public function alias($abstract, $alias)
{
$this->aliases[$alias] = $abstract;
}
/**
* Extract the type and alias from a given definition.
*
* @param array $definition
* @return array
*/
protected function extractAlias(array $definition)
{
return array(key($definition), current($definition));
}
/**
* Resolve the given type from the container.
*
* @param string $abstract
* @param array $parameters
* @return mixed
*/
public function make($abstract, $parameters = array())
{
$abstract = $this->getAlias($abstract);
// If an instance of the type is currently being managed as a singleton we'll
// just return an existing instance instead of instantiating new instances
// so the developer can keep using the same objects instance every time.
if (isset($this->instances[$abstract]))
{
return $this->instances[$abstract];
}
$concrete = $this->getConcrete($abstract);
// We're ready to instantiate an instance of the concrete type registered for
// the binding. This will instantiate the types, as well as resolve any of
// its "nested" dependencies recursively until all have gotten resolved.
if ($this->isBuildable($concrete, $abstract))
{
$object = $this->build($concrete, $parameters);
}
else
{
$object = $this->make($concrete, $parameters);
}
// If the requested type is registered as a singleton we'll want to cache off
// the instances in "memory" so we can return it later without creating an
// entirely new instance of an object on each subsequent request for it.
if ($this->isShared($abstract))
{
$this->instances[$abstract] = $object;
}
$this->fireResolvingCallbacks($object);
return $object;
}
/**
* Get the concrete type for a given abstract.
*
* @param string $abstract
* @return mixed $concrete
*/
protected function getConcrete($abstract)
{
// If we don't have a registered resolver or concrete for the type, we'll just
// assume each type is a concrete name and will attempt to resolve it as is
// since the container should be able to resolve concretes automatically.
if ( ! isset($this->bindings[$abstract]))
{
return $abstract;
}
else
{
return $this->bindings[$abstract]['concrete'];
}
}
/**
* Instantiate a concrete instance of the given type.
*
* @param string $concrete
* @param array $parameters
* @return mixed
*/
public function build($concrete, $parameters = array())
{
// If the concrete type is actually a Closure, we will just execute it and
// hand back the results of the functions, which allows functions to be
// used as resolvers for more fine-tuned resolution of these objects.
if ($concrete instanceof Closure)
{
return $concrete($this, $parameters);
}
$reflector = new \ReflectionClass($concrete);
// If the type is not instantiable, the developer is attempting to resolve
// an abstract type such as an Interface of Abstract Class and there is
// no binding registered for the abstractions so we need to bail out.
if ( ! $reflector->isInstantiable())
{
$message = "Target [$concrete] is not instantiable.";
throw new BindingResolutionException($message);
}
$constructor = $reflector->getConstructor();
// If there are no constructors, that means there are no dependencies then
// we can just resolve the instances of the objects right away, without
// resolving any other types or dependencies out of these containers.
if (is_null($constructor))
{
return new $concrete;
}
$parameters = $constructor->getParameters();
// Once we have all the constructor's parameters we can create each of the
// dependency instances and then use the reflection instances to make a
// new instance of this class, injecting the created dependencies in.
$dependencies = $this->getDependencies($parameters);
return $reflector->newInstanceArgs($dependencies);
}
/**
* Resolve all of the dependencies from the ReflectionParameters.
*
* @param array $parameters
* @return array
*/
protected function getDependencies($parameters)
{
$dependencies = array();
foreach ($parameters as $parameter)
{
$dependency = $parameter->getClass();
// If the class is null, it means the dependency is a string or some other
// primitive type which we can not resolve since it is not a class and
// we'll just bomb out with an error since we have no-where to go.
if (is_null($dependency))
{
$dependencies[] = $this->resolveNonClass($parameter);
}
else
{
$dependencies[] = $this->make($dependency->name);
}
}
return (array) $dependencies;
}
/**
* Resolve a non-class hinted dependency.
*
* @param ReflectionParameter $parameter
* @return mixed
*/
protected function resolveNonClass(ReflectionParameter $parameter)
{
if ($parameter->isDefaultValueAvailable())
{
return $parameter->getDefaultValue();
}
else
{
$message = "Unresolvable dependency resolving [$parameter].";
throw new BindingResolutionException($message);
}
}
/**
* Register a new resolving callback.
*
* @param Closure $callback
* @return void
*/
public function resolving(Closure $callback)
{
$this->resolvingCallbacks[] = $callback;
}
/**
* Fire all of the resolving callbacks.
*
* @param mixed $object
* @return void
*/
protected function fireResolvingCallbacks($object)
{
foreach ($this->resolvingCallbacks as $callback)
{
call_user_func($callback, $object);
}
}
/**
* Determine if a given type is shared.
*
* @param string $abstract
* @return bool
*/
protected function isShared($abstract)
{
$set = isset($this->bindings[$abstract]['shared']);
return $set and $this->bindings[$abstract]['shared'] === true;
}
/**
* Determine if the given concrete is buildable.
*
* @param mixed $concrete
* @param string $abstract
* @return bool
*/
protected function isBuildable($concrete, $abstract)
{
return $concrete === $abstract or $concrete instanceof Closure;
}
/**
* Get the alias for an abstract if available.
*
* @param string $abstract
* @return string
*/
protected function getAlias($abstract)
{
return isset($this->aliases[$abstract]) ? $this->aliases[$abstract] : $abstract;
}
/**
* Get the container's bindings.
*
* @return array
*/
public function getBindings()
{
return $this->bindings;
}
/**
* Determine if a given offset exists.
*
* @param string $key
* @return bool
*/
public function offsetExists($key)
{
return isset($this->bindings[$key]);
}
/**
* Get the value at a given offset.
*
* @param string $key
* @return mixed
*/
public function offsetGet($key)
{
return $this->make($key);
}
/**
* Set the value at a given offset.
*
* @param string $key
* @param mixed $value
* @return void
*/
public function offsetSet($key, $value)
{
// If the value is not a Closure, we will make it one. This simply gives
// more "drop-in" replacement functionality for the Pimple which this
// container's simplest functions are base modeled and built after.
if ( ! $value instanceof Closure)
{
$value = function() use ($value)
{
return $value;
};
}
$this->bind($key, $value);
}
/**
* Unset the value at a given offset.
*
* @param string $key
* @return void
*/
public function offsetUnset($key)
{
unset($this->bindings[$key]);
}
}