How do I set response models to not be optional as typescript is saying a value can be undefined when it can never be the case.

I’m using fast endpoints with a typescript client automatically generated from the Open API specification generated by Fast Endpoints.

I have response models which I know they will always have a value, however, currently the response models are being created with all fields being marked as nullable, for example:

    id?: string;
    name?: string;
    headerImage?: string;

my understanding is that this is happening because the Open API definition is created as per the below:

    "schemas": {
      "Response": {
        "type": "object",
        "additionalProperties": false,
        "properties": {
          "id": {
            "type": "string"
          },
          "name": {
            "type": "string"
          },
          "headerImage": {
            "type": "string"
          }
        }
      },

I’d like to generate this definition instead:

    "schemas": {
      "Response": {
        "type": "object",
        "required": [
          "id",
          "name",
        ],
        "additionalProperties": false,
        "properties": {
          "id": {
            "type": "string"
          },
          "name": {
            "type": "string"
          },
          "headerImage": {
            "type": "string"
          }
        }
      },

Is it possible to create this OpenAPI definition?

[dj-nitehawk]

added an extension method in 5.8.1.14-beta

builder.Services.AddSwaggerDoc(x =>
{
    x.MarkNonNullablePropsAsRequired();
});

[rubenmamo]

Thanks for the update. I can confirm that the code above is a valid workaround, however, I think there will be some cases where this wouldn’t work, particularly if you don’t enable the nullable reference types feature of C#8. From what I can gather, the IsNullable function listed above doesn’t return true for arrays, strings or reference types which means that unless you enable nullable reference types this functionality will probably cause issues down the line in clients. I will do some further investigation and will update the issue with any information.