OpenAPI and validation

Validation of input data in HTTP requests is based on metadata transmitted to @OasRoute() (OAS is "OpenAPI Specification"). Before starting the web server, ValidationExtension analyzes this metadata, and if it is declared in a particular route that the request may come with parameters or the body, ValidationInterceptor is added to this route.

However, not all metadata accepted in @OasRoute() is taken into account for validation. The following is currently being tested:

number: availability of parameter, minimum and maximum value;
string: availability of parameter, minimum and maximum length;
boolean: availability of parameter and valid values (0, 1, true, false);
object: availability of parameter; a recursive pass is made for each property with the check described in all items of this list (number, string, boolean, object, array);
array: availability of parameter, the minimum and maximum number of items, as well as the check described in all items of this list (number, string, boolean, object, array) for each items.

OasOperationObject

To facilitate the transfer of metadata to @OasRoute(), a helper OasOperationObject has been created. Each method in this class is prefixed with set* or get*. Each of the methods with the prefix set* returns a reference to the instance of OasOperationObject, so you can call several methods in a chain:

@OasRoute('GET', ':slug', [], {
  ...new OasOperationObject()
    .setOptionalParams('query', Params, 'tag', 'author', 'limit', 'offset')
    .setResponse(ArticleItem, 'Description for response content.')
    .setUnauthorizedResponse()
    .getNotFoundResponse('The article not found.'),
})
async getArticle() {
  // ...
}

As you can see, methods with the prefix set* are called three times and at the very end - once with the prefix get*. This is an important point: "Each use of the OasOperationObject instance must end with a method call with the prefix get*".

Note that Params and ArticleItem here are the classes that act here as data models from which the OasOperationObject helper reads metadata. To pin metadata for each model, use the @Column() decorator:

import { Column } from '@ditsmod/openapi';

export class ArticleItem {
  @Column()
  article: Article;
}

OasOperationObject​

OasOperationObject