Any plans to support only and except?

[frysch]

Hi there!

In the process of migrating from ams to this little beauty, and wondering if there's any plans to support only and except to only serialize some attributes?

[ElMassimo]

Hi Anders!

One of the reasons this library is more performant is that the code for serialization is generated at load time.

Supporting only and except would require dynamically iterating the list of attributes to find out which ones to render, which is slower.

I'd be open to supporting it if we find an implementation that does not negatively affect the default case. That might require using a different execution path when only or except are provided.

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As a workaround when migrating from AMS or similar libraries, you can use the if option in an attribute, for example:

attribute :name, if: -> { !options[:except]&.include?(:name) }

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For performance (and for robustness if generating types from serializers), it's better to avoid conditional attributes, and instead use different serializers when you need different attributes.