Create model instance from plain-data object at controller methods

[jonathansolorzn]

Suggestion

When method hits with a request body we can set it to have a model type, but in the method body the model is just plain-data object.

Use Cases

Since models are classes I'd like to create computed properties for the model like getters, and also have functions to calculate stuff based on the properties that the class has.

Examples

@post('/cards/')
  async create(
    @requestBody({
      content: {
        'application/json': {
          schema: getModelSchemaRef(Card, {
            title: 'Card'
          }),
        },
      },
    })
    card: Card,
  ): Promise<CardResponse> {
    // Trying to access a computed property of Card form `card` variable is no possible here
    console.log(card.computedGetProperty) //outputs undefined
  }

Acceptance criteria

TBD - will be filled by the team.

[InvictusMB]

This looks more like a bug to me. If I expect a Card instance, I should get a Card instance not a POJO.
Otherwise the definition should say something like card: Raw<Card>

But for now, wouldn't new Card(card).computedGetProperty() do the job for you?

[jonathansolorzn]

Yeah @InvictusMB I did that

[dhmlau]

Does this docs page provide something you're looking for? https://github.com/strongloop/loopback-next/blob/master/docs/site/Dynamic-models-repositories-controllers.md

cc @hacksparrow

[hacksparrow]

Requirement is not very clear to me.

[InvictusMB]

@hacksparrow
The issue is that an object passed to the controller method does not match the signature of that method. In the example above we have a Card in the signature but get a plain JS object of a similar shape instead of a Card class instance.

This is somewhat related to #2707

[jannyHou]

Thank you @InvictusMB seems this story is asking for the same feature as #2707. @fenixsolorzano do you mind if we move all the discussion there? (trying to keep the backlog smaller)

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This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[stale]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.