Proposal

An option for serde Serialize/Deserialize of ActiveModel, ActiveValue and Value

Motivation

Possible use cases:

1. to log db write activities for debugging purposes (the one I am interested in): to better pinpoint bugs and erroneous behavior, I would like to store in a table or file the ActiveModels that generated insert/update/delete operations so that I know exactly with what parameters the model was called with
2. to have the history of a database for data recovery/reconstruction/integrity: when data are valuable, the ability to start from a snapshot of the Db and simply re-perform some or all of the write operations is handy
3. to help with the dyn unsafe traits of SeaORM: when you want to construct functions that perform operations on a variety of ActiveModels and Models, the 'impl ActiveModelTrait' is not a solution because it is dyn unsafe. Having the ability to serialize/deserialize the model makes the operation a lot easier

SeaORM offers the option to add serde Serialize/Deserialize for Model, but transforming the ActiveModel into a Model and serializing it loses important information such as Set/Unset/Unchanged status for each field.

Implementation

At a first glance of the source code, the implementation should be easy and straightforward, requiring only some incremental and non-disrupting changes to the code.

I manually copied/pasted some ActiveModel/ActiveValue/Value in my code and it compiled flawlessly, so there is nothing not serde-safe in the ActiveModel/ActiveValue/Value.

It is required only to add a derive Serialize/Deserialize to the template (as Model has) and the logic to implement it