PHP: use __debugInfo in Message to fix endless var_dump #12714
Description
Debugging a Protobuf Message Object
Calling var_dump or print_r on a protobuf message with the Protobuf C extension enabled results very limited, not very useful output:
// Calling var_dump on a Protobuf message (extension enabled):
php > var_dump(new Google\Protobuf\Timestamp());
object(Google\Protobuf\Timestamp)#1 (0) {
}
// Calling print_r on a Protobuf message (extension enabled):
php > var_dump(new Google\Protobuf\Timestamp());
Google\Protobuf\Timestamp Object
When using the Protobuf native library, calls to var_dump and print_r are hard to read and filled with noise:
// Calling var_dump on a Protobuf message (extension disabled):
php > var_dump(new Google\Protobuf\Timestamp());
object(Google\Protobuf\Timestamp)#2 (4) {
["desc":"Google\Protobuf\Internal\Message":private]=>
object(Google\Protobuf\Internal\Descriptor)#424 (13) {
["full_name":"Google\Protobuf\Internal\Descriptor":private]=>
string(25) "google.protobuf.Timestamp"
["field":"Google\Protobuf\Internal\Descriptor":private]=>
array(2) {
[1]=>
object(Google\Protobuf\Internal\FieldDescriptor)#428 (14) {
["name":"Google\Protobuf\Internal\FieldDescriptor":private]=>
string(7) "seconds"
["json_name":"Google\Protobuf\Internal\FieldDescriptor":private]=>
string(7) "seconds"
["setter":"Google\Protobuf\Internal\FieldDescriptor":private]=>
string(10) "setSeconds"
["getter":"Google\Protobuf\Internal\FieldDescriptor":private]=>
string(10) "getSeconds"
["number":"Google\Protobuf\Internal\FieldDescriptor":private]=>
int(1)
["label":"Google\Protobuf\Internal\FieldDescriptor":private]=>
int(1)
["type":"Google\Protobuf\Internal\FieldDescriptor":private]=>
int(3)
["message_type":"Google\Protobuf\Internal\FieldDescriptor":private]=>
NULL
["enum_type":"Google\Protobuf\Internal\FieldDescriptor":private]=>
NULL
["packed":"Google\Protobuf\Internal\FieldDescriptor":private]=>
bool(false)
["oneof_index":"Google\Protobuf\Internal\FieldDescriptor":private]=>
int(-1)
["proto3_optional":"Google\Protobuf\Internal\FieldDescriptor":private]=>
bool(false)
["containing_oneof":"Google\Protobuf\Internal\FieldDescriptor":private]=>
NULL
["public_desc":"Google\Protobuf\Internal\FieldDescriptor":private]=>
object(Google\Protobuf\FieldDescriptor)#429 (1) {
["internal_desc":"Google\Protobuf\FieldDescriptor":private]=>
*RECURSION*
}
}
// ...
// Calling print_r on a Protobuf message (extension disabled):
php > var_dump(new Google\Protobuf\Timestamp());
Google\Protobuf\Timestamp Object
(
[desc:Google\Protobuf\Internal\Message:private] => Google\Protobuf\Internal\Descriptor Object
(
[full_name:Google\Protobuf\Internal\Descriptor:private] => google.protobuf.Timestamp
[field:Google\Protobuf\Internal\Descriptor:private] => Array
(
[1] => Google\Protobuf\Internal\FieldDescriptor Object
(
[name:Google\Protobuf\Internal\FieldDescriptor:private] => seconds
[json_name:Google\Protobuf\Internal\FieldDescriptor:private] => seconds
[setter:Google\Protobuf\Internal\FieldDescriptor:private] => setSeconds
[getter:Google\Protobuf\Internal\FieldDescriptor:private] => getSeconds
[number:Google\Protobuf\Internal\FieldDescriptor:private] => 1
[label:Google\Protobuf\Internal\FieldDescriptor:private] => 1
[type:Google\Protobuf\Internal\FieldDescriptor:private] => 3
[message_type:Google\Protobuf\Internal\FieldDescriptor:private] =>
[enum_type:Google\Protobuf\Internal\FieldDescriptor:private] =>
[packed:Google\Protobuf\Internal\FieldDescriptor:private] =>
[oneof_index:Google\Protobuf\Internal\FieldDescriptor:private] => -1
[proto3_optional:Google\Protobuf\Internal\FieldDescriptor:private] =>
[containing_oneof:Google\Protobuf\Internal\FieldDescriptor:private] =>
[public_desc:Google\Protobuf\Internal\FieldDescriptor:private] => Google\Protobuf\FieldDescriptor Object
(
[internal_desc:Google\Protobuf\FieldDescriptor:private] => Google\Protobuf\Internal\FieldDescriptor Object
*RECURSION*
//...
This problem is even worse when debugging instances of RepeatedField, as the result is never-ending.
The fix for this would involve adding support for __debugInfo in the Message class:
public function __debugInfo()
{
return (array) json_decode($this->serializeToJsonString(), true);
}For better handling , we can add support for checking specific types (e.g. Google\Protobuf\Timestamp, which returns a string for serializeToJsonString) and adding __debugInfo() for specific classes such as RepeatedField.