v3.0: Issue with discriminator generating request DTO

[souravk]

Hello Team,

I am trying to implement polymorphism using OpenAPI by generating a class and child classes. Let's say I want to generate a class Class B that extends Class A. It has been generated using discriminantor function, which is good. But no, the issue is when I want to call it from Postman or another app by passing a JSON string, it returns 400 Bad Request. It's because I need to pass the type that mentioned the discriminator. But as this request dto used by another team, I don't want to change the payload structure. How can we achieve this? I want to keep the class generated as the same Class B extends A.

Thanks!

[handrews]

@souravk My understanding is that you want to pass a string, but using discriminator requires an object. If that is true, there is nothing we can do for you, as there is no way for discriminator to work with just a string. Is this correct.

[souravk]

Thanks for the reply.

I want to pass this
{
"appCd":"",
"uid":"","",
"appId":""
}

where A class has attributes appCd. and B class have attributes ui and appId. I added this in schema in Parent A class

disciminator:
propertyName: "type"
mapping:
a: A

Now, when I am using Postman to send a request, I need to pass "type":"a" along with the above payload. If I don't pass it, it will throw a 400 Bad Request. I dont want to pass this type attribute in the payload during the request.

[handrews]

@handrews the way discriminator works is that you need to have a field that provides the value on which the subclass is selected. In OAS v3.2 (released this past week so not supported by tools yet), that field can be omitted and a default subclass can be provided. But there is no way to select among multiple subclasses without a field, and no way to select with the field omitted in OAS 3.0 or 3.1.