Add example for using dataclasses with marshmallow-dataclass

[mmdbalkhi]

• fixes Add support for marshmallow-dataclass #242

Checklist:

• Add tests that demonstrate the correct behavior of the change. Tests should fail without the change.
• Add or update relevant docs, in the docs folder and in code docstring.
• Add an entry in CHANGES.md summarizing the change and linking to the issue and your username.
• Add *Version changed* or *Version added* note in any relevant docs and docstring.
• Run pytest and tox, no tests failed.

[greyli]

Thank you for working on this. However, after reading marshmallow-dataclass's docs and issue list, I think it's not a good idea to add direct support in APIFlask for it. For example:

• It generates unnecessary default description value for fields.
• User needs to use the nested metadata keyword to pass field info and actual metadata info, it's verbose and hard to write.
• etc.

IMO, It's not mature enough. Users can just install this library and convert the dataclasses to schema before passing it to app.input()/app.output().

Could you refactor this PR to keep only the docs and the example application?

Besides, as I said in the review comment, the custom field should be set with dataclasses.field() instead of marshmallow_dataclass.NewType(). Here is an example from marshmallow-dataclass's README:

from dataclasses import dataclass, field
import marshmallow_dataclass
import marshmallow.validate


@dataclass
class Person:
    name: str = field(
        metadata=dict(
            load_only=True, metadata=dict(description="The person's first name")
        )
    )
    height: float = field(metadata=dict(validate=marshmallow.validate.Range(min=0)))

Sorry for changing my mind, I didn't think it through when I create that issue.

[mmdbalkhi]

np. likely I'll work on it tomorrow

This is how I found out, is it true?

• we just keep docs and example
• we do not need to support dataclass for built-in on the apiflask

do I have to delete previous commits or you are with Squash merging PR to main?
and What will the docs look like? like this?

[mmdbalkhi]

For the sake of PR cleanliness, I resolve reviews

[greyli]

we just keep docs and example
we do not need to support dataclass for built-in on the apiflask

Yes, we introduce how to use marshmallow-dataclass with APIFlask, the docs will like this:

• A general introduction of how it works.
• How to install the library (pip install marshmallow-dataclass).
• Example to create dataclasses for input and output data.
• Example to convert the dataclasses to marshmallow schema when passing it to app.input()/app.output (i.e. PetOut.Schema).

do I have to delete previous commits or you are with Squash merging PR to main?

You can rebase the commits or I will squash them.

[mmdbalkhi]

@greyli I've done but I can't add marshmallow-dataclass to the requirements due pip-tools have a problem with new pip versions

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[mmdbalkhi]

@greyli I do not know exactly how to solve this problem. Do you have a suggestion? Requirements files are also created by pip-compile-multi.

[greyli]

Just revert the changes to requirements files, I will update them later.

[greyli]

There are some typos and grammar errors in the docs, and the example application is not actually working. Please fix these issues.

[greyli]

The object passed to APIFlask should always be a schema (i.e. dataclass.Schema).

[greyli]

The Pet should be Pet.Schema.

[greyli]

This if statement makes no sense.

[greyli]

The object passed to APIFlask should always be a schema (i.e. dataclass.Schema).

[greyli]

The description here does not seem to be related to the following example.

[greyli]

It seems unnecessary to convert the data objec to dict, why don't just do this:

pets[pet_id].name = data.name 
pets[pet_id].category = data.category

[greyli]

Please check the two remaining review comments.

[mmdbalkhi]

Please check the two remaining review comments.

yes, sorry. I think All is done. If there is a problem, please tell me to solve it

[greyli]

Merged, thanks!