feat(plugin) add support for @Expose() and @Exclude() decorators

[kurt-west]

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• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
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PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

The Swagger plugin will automatically annotate all DTO properties with @ApiProperty unless @ApiHideProperty is used.

Issue Number: #2603

What is the new behavior?

This PR adds support to include or hide DTO properties from the generated OpenAPI definitions via the existing class-transformer decorators.

The new classTransformerShim option can be set to one of the following:

• false: No changes to the current behavior
• true: Any property decorated with @Exclude() will be hidden from the the generated definition; same behavior as @ApiHideProperty()
• 'exclusive': Only properties that are decorated with @Expose() or @ApiProperty will be included in the generated definition

NOTE: default is classTransformerShim: false

Does this PR introduce a breaking change?

• Yes
• No

Other information

Small unrelated change to test/plugin/readonly-visitor.spec.ts to help with test failing due to end-of-line characters differences between host machine and PluginMetadataPrinter output.

Edit: grammar

[kamilmysliwiec]

LGTM

[gustavopedroni]

👀

[gustavopedroni]

@kurt-west
It not working when @expose or @exclude is decorating a class

[kurt-west]

@kurt-west It not working when @expose or @exclude is decorating a class

@gustavopedroni - this PR follows the existing plugin pattern of decorating properties, not classes.

The class visitor could be updated to pass @expose()/@exclude() metadata down to the property visitor to match the class-transformer pattern of class or property decoration. @kamilmysliwiec - if you'd support this I can submit a PR.

[kalu06]

Thanks for this contribution, that's a great feature.
While playing with it, it seems to not take into account @Expose groups, making it impossible to have correct Swagger definition when reusing the same DTO but with different serialization groups.

Any idea how to achieve that?

Thanks

[kurt-west]

@kalu06

How it works:
The implementation of this feature is based on the existing decision logic of the @ApiProperty() and @ApiHideProperty() decorators. Ignoring the annotateAllProperties: true option, if a property is decorated with @ApiProperty() or @Expose() it is allowed to pass onto the property inspection method.

Is it possible:
If you can manually generate your desired schema using the @ApiProperty() decorator with only the knowledge of the class-transformer decorator arguments and the property itself then it should technically be possible to update the property inspector to generate the desired schema.

If you post a manually generated dto I can dig deeper and see if we can come up with a feature proposal for the Nest team.

[kurt-west]

@kurt-west It not working when @expose or @exclude is decorating a class

@gustavopedroni - this PR follows the existing plugin pattern of decorating properties, not classes.

The class visitor could be updated to pass @expose()/@exclude() metadata down to the property visitor to match the class-transformer pattern of class or property decoration. @kamilmysliwiec - if you'd support this I can submit a PR.

@gustavopedroni
I have have class-level expose/exclude working in my personal project, if I don't run into any issues by the end of the month I'll submit a PR.

[thw0rted]

Hi @kurt-west , did you ever wind up submitting the PR for class-level exclude? I didn't see it in a cursory search so I figured I'd ask.