Invalid OAS file generation for Page

[rolikoff]

I'm currently integrating a library with my FastAPI project and utilizing the following library versions:

[tool.poetry.dependencies]
python = "~3.12.0"
fastapi = "~0.110.0"
fastapi-pagination = "~0.12.21"

I've established a test route within my project as follows:

@router.get("/")
async def domains() -> Page[Domain]:
    domains = [Domain(id=1, name="test"), Domain(id=2, name="test2")]
    return paginate(domains)

However, I've encountered an issue with the OpenAPI Specification (OAS) YAML file generated, as it includes incorrect schema types:

openapi: 3.0.2
...

    Page_Domain_:
     properties:
       items:
         items:
           $ref: '#/components/schemas/Domain'
         type: array
         title: Items
       total:
         anyOf:
         - type: integer
           minimum: 0.0
         - type: 'null'
         title: Total
       page:
         anyOf:
         - type: integer
           minimum: 1.0
         - type: 'null'
         title: Page
       size:
         anyOf:
         - type: integer
           minimum: 1.0
         - type: 'null'
         title: Size
       pages:
         anyOf:
         - type: integer
           minimum: 0.0
         - type: 'null'
         title: Pages

I understand that OAS version 3.0.2 does not support null types, which may not be a direct issue with fastapi-pagination. Minimum values are not ints, which is odd as well. Could you provide any insights into the underlying problem or suggest a possible solution?

[uriyyo]

Hi @rolikoff,

Could you please show how you generate OpenAPI schema?

Here is what component definition looks like in my case:

from fastapi import FastAPI

from fastapi_pagination import Page, add_pagination, paginate

app = FastAPI()
add_pagination(app)


@app.get("/")
async def get_items() -> Page[int]:
    return paginate([])

{
    "Page_int_": {
        "properties": {
            "items": {
                "items": {
                    "type": "integer"
                },
                "type": "array",
                "title": "Items"
            },
            "total": {
                "type": "integer",
                "minimum": 0.0,
                "title": "Total"
            },
            "page": {
                "type": "integer",
                "minimum": 1.0,
                "title": "Page"
            },
            "size": {
                "type": "integer",
                "minimum": 1.0,
                "title": "Size"
            },
            "pages": {
                "type": "integer",
                "minimum": 0.0,
                "title": "Pages"
            }
        },
        "type": "object",
        "required": [
            "items"
        ],
        "title": "Page[int]"
    }
}

But it use 3.1.0 OpenAPI version.