Feature Request: Add option to infer wrapped lists when generating python code from XSD

[couling]

Wrapped lists are really useful for simplifying python data structures. Looking through the documentation, I don't see any way to make this work with xsdata generate <xsd file>.

It would be really useful to have an option to infer wrapped lists where one data class will contain another dataclass, itself only containing a list. This may be something that can be post-processed between schema transformation and python code writer.

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I don't see any documentation on the "Pluggable code writer for custom output formats". So this customisation isn't something that can be easily bolted on from the side.

I certainly don't want to manually modify python code after parsing a sizeable XSD where the XSD is subject to change.

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It could be optional which name is kept for the python name, but I'd recommend it default to the wrapper name, not the element name for these reasons:

• XML schema don't commonly mix and match between wrapped lists and unwrapped lists. If they have wrapper elements at all then all lists are likely to be wrapped lists.
• Wrappers are most commonly name the list, inner elements name the type of thing in the list.

Eg:

<person><children><child>Bob</child><children></person>

most naturally converts to

Person(children=["Bob"])

It makes much less sense to convert this to Person(child=["bob"])

[tefra]

It should be part of the code generator, I agree.

[couling]

If I was to look at the possible code for this would it be better to process this in the transform step (which would need a wrapper attribute adding somewhere to the model), or would it be better to add as a feature of the output writer?

[couling]

I've not forgotten this. Just ran out of free time. I'll be back ;-)

[tefra]

This is on my immediate todo list @couling

[tefra]

@couling are you working with a specific schema?

[couling]

I am. But sadly it's proprietary and I don't have authorisation to share it.

[tefra]

I added a new cli config option --wrapper-fields

This is what it does on the w3c-test suite.
tefra/xsdata-w3c-tests@65c0342

Give it a try and let me know how it works for your use case @couling