Enh. #20171 - possible breaking changes: Support JSON columns for MariaDB 10.4 or higher.

[ldkafka]

If prior to Yii2 2.0.50 a MariaDB JSON field was used in a model, the contents needed manual json_encode before save (otherwise MySQL errored because of invalid JSON data).

Issue 1: Since this change, a manual json_encode on the field before assigning this to an AR attribute is basically double-encoding the data - data_type -> JSON string -> JSON.
Issue 2: If the JSON attribute used to have a 'string' validator in the model (which was the closest to no validator at all), now the validation fails if the original data type is not a string.

I realize these are not directly Yii issues, but they are Yii changes that break existing code behavior.

Short of testing if the attribute already is a valid JSON string before the encoding in the query builder, I'm not sure what the solution may be...

[manky]

The change also impact the yii\behaviors\AttributeTypecastBehavior on line 269 with the following error Array to string conversion

[terabytesoftw]

The JSON column behavior in MariaDB was wrong, it was corrected and now it works the same as MySQL, you can check it in the tests, can you explain to me how this affects AttributeTypeCastBehavior::class.

2.0.49.4 will also be released, with the security patches, if you do not need to change anything in your application you can use 2.0.49.4 when it is released, if you want to use 2.0.50, then you must update the code for the use of the JSON column in MariaDB.

It is certainly BC, but it is a necessary error correction, now all MySQL/MariaDB tests pass correctly.

Related: #18390

[ldkafka]

I don't thing we should revert the change - it is definitely a step in the right direction, however, it does break existing code. Maybe all it needs is a warning in big letters that this may break code...

[terabytesoftw]

I don't thing we should revert the change - it is definitely a step in the right direction, however, it does break existing code. Maybe all it needs is a warning in big letters that this may break code...

Thanks for the suggestion, i'll add the note.

[manky]

The JSON column behavior in MariaDB was wrong, it was corrected and now it works the same as MySQL, you can check it in the tests, can you explain to me how this affects AttributeTypeCastBehavior::class.

2.0.49.4 will also be released, with the security patches, if you do not need to change anything in your application you can use 2.0.49.4 when it is released, if you want to use 2.0.50, then you must update the code for the use of the JSON column in MariaDB.

It is certainly BC, but it is a necessary error correction, now all MySQL/MariaDB tests pass correctly.

Related: #18390

I will do some more tests and will give you an update about the AttributeTypecastBehavior

[manky]

The problem is caused by the default validation rules in the model.
In the previous version of the Yii2, using GII, JSON fields in the database was validated by yii\validators\StringValidator, from version 2.0.50 they are validated by the yii\validators\SafeValidator.

Depending on the configuration of the AttributeTypecastBehavior, the value will be detected automatically based on validation rules.

So everyone needs to make changes on their models, before updating to v2.0.50.