#34593 [Csd]: Unintuitive serialization for inherited objects.
ID: 34593 User updated by: ectsue at gmail dot com Reported By: ectsue at gmail dot com Status: Closed Bug Type: Feature/Change Request Operating System: * PHP Version: 5.0.* New Comment: tony: In the project that I ran into this problem, I use the __sleep method to return only a subset of the member variables of the class. An object of this class can get to be rather large and I do not need to serialize everything. This class is occasionally used as a superclass for other classes (this is where I ran into the problem). So, I do need that __sleep function. Previous Comments: [2005-09-22 10:45:30] [EMAIL PROTECTED] This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better. Have a look at interface serializable in 5.1 [2005-09-22 10:45:30] [EMAIL PROTECTED] This code (with __sleep() removed) works perfecty fine: ?php class A { private $a; public function getA() { return $this-a; } public function setA($a) { $this-a = $a; } } class B extends A { } $b = new B(); $b-setA(10); $bSerialized = serialize($b); $bUnserialized = unserialize($bSerialized); var_dump($b); var_dump($bUnserialized); ? Is this what you need? [2005-09-22 07:00:26] ectsue at gmail dot com Description: I believe that the way serialization works for objects doesn't make sense. I have a subclass whose superclass contains a private member variable. Upon serialization, I cannot get the private member variable to serialize for the subclass (except by using a NUL class-name NUL member-name string in __sleep()). Imho, subclasses shouldn't have to know what parts of their parent classes to serialize. I can think of two possible solutions to this problem: 1. Have serialize() walk the inheritance tree for the object it is serializing. 2. Have some method that will be able to take the output from parent::__sleep() and modify it so that it can be passed back from the __sleep() method of the subclass so that private member variables in the parent can be serialized. (The function I have in mind would do the NUL class-name NUL member-name transformation). Reproduce code: --- class A { private $a; public function __sleep() { return array('a'); } public function getA() { return $this-a; } public function setA($a) { $this-a = $a; } } class B extends A { } $b = new B(); $b-setA(10); $bSerialized = serialize($b); $bUnserialized = unserialize($bSerialized); var_dump($b); var_dump($bUnserialized); Expected result: object(B)#1 (1) { [a:private]= int(10) } object(B)#1 (1) { [a:private]= int(10) } Actual result: -- object(B)#1 (1) { [a:private]= int(10) } object(B)#2 (2) { [a:private]= NULL [a]= NULL } -- Edit this bug report at http://bugs.php.net/?id=34593edit=1
#34593 [Csd]: Unintuitive serialization for inherited objects.
ID: 34593 User updated by: ectsue at gmail dot com Reported By: ectsue at gmail dot com Status: Closed Bug Type: Feature/Change Request Operating System: * PHP Version: 5.0.* New Comment: helly: Where can I find documentation about the serializable interface? I tried a whole site search on php.net and couldn't find anything of interest. Previous Comments: [2005-09-22 21:10:28] ectsue at gmail dot com tony: In the project that I ran into this problem, I use the __sleep method to return only a subset of the member variables of the class. An object of this class can get to be rather large and I do not need to serialize everything. This class is occasionally used as a superclass for other classes (this is where I ran into the problem). So, I do need that __sleep function. [2005-09-22 10:45:30] [EMAIL PROTECTED] This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better. Have a look at interface serializable in 5.1 [2005-09-22 10:45:30] [EMAIL PROTECTED] This code (with __sleep() removed) works perfecty fine: ?php class A { private $a; public function getA() { return $this-a; } public function setA($a) { $this-a = $a; } } class B extends A { } $b = new B(); $b-setA(10); $bSerialized = serialize($b); $bUnserialized = unserialize($bSerialized); var_dump($b); var_dump($bUnserialized); ? Is this what you need? [2005-09-22 07:00:26] ectsue at gmail dot com Description: I believe that the way serialization works for objects doesn't make sense. I have a subclass whose superclass contains a private member variable. Upon serialization, I cannot get the private member variable to serialize for the subclass (except by using a NUL class-name NUL member-name string in __sleep()). Imho, subclasses shouldn't have to know what parts of their parent classes to serialize. I can think of two possible solutions to this problem: 1. Have serialize() walk the inheritance tree for the object it is serializing. 2. Have some method that will be able to take the output from parent::__sleep() and modify it so that it can be passed back from the __sleep() method of the subclass so that private member variables in the parent can be serialized. (The function I have in mind would do the NUL class-name NUL member-name transformation). Reproduce code: --- class A { private $a; public function __sleep() { return array('a'); } public function getA() { return $this-a; } public function setA($a) { $this-a = $a; } } class B extends A { } $b = new B(); $b-setA(10); $bSerialized = serialize($b); $bUnserialized = unserialize($bSerialized); var_dump($b); var_dump($bUnserialized); Expected result: object(B)#1 (1) { [a:private]= int(10) } object(B)#1 (1) { [a:private]= int(10) } Actual result: -- object(B)#1 (1) { [a:private]= int(10) } object(B)#2 (2) { [a:private]= NULL [a]= NULL } -- Edit this bug report at http://bugs.php.net/?id=34593edit=1