Bug: default not generated for query parameter in openapi spec.

[globglarb]

Description

Hi,

The default of a query parameter is not properly generated when creating the openapi specification. See MVCE down below.

The generated specification looks like this:

...
"paths": {
    "/query_default": {
      "get": {
        "summary": "QueryDefault",
        "operationId": "QueryDefaultQueryDefault",
        "parameters": [
          {
            "name": "foo",
            "in": "query",
            "schema": {
              "type": "integer"
            },
            "required": false,
            "deprecated": false,
            "allowEmptyValue": false,
            "allowReserved": false
          }
        ],
...

where the default is missing in the schema property.

URL to code causing the issue

No response

MCVE

@get(path="query_default")
def query_default(foo: int = 12) -> None:
    return

app = Litestar(route_handlers=[query_default])

Steps to reproduce

No response

Screenshots

No response

Logs

No response

Litestar Version

Version 2.7.1

Platform

• Linux
• Mac
• Windows
• Other (Please specify in the description above)

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[JacobCoffee]

Could you confirm that this is also true in 2.7.0?

[globglarb]

Same result with fixed version 2.7.0

dependencies = [
    "litestar[standard]==2.7.0"
]

[JacobCoffee]

Thanks!

[guacs]

I don't think this is a bug. The specification doesn't have a field to indicate a default value for parameters.

[guacs]

Sorry about that. I was completely wrong. While it's correct that the parameter object as per the spec doesn't allow for defaults, it does allow for a schema which can have a default value.

Us not parsing the default properly is a bug.

[Alc-Alc]

Just leaving this here in case you need a workaround. You can use Annotated[int, Parameter(default=12)] to get the behavior you expect.

from typing_extensions import Annotated
from litestar import Litestar, get
from litestar.params import Parameter

@get(path="query_default")
async def query_default(foo: Annotated[int, Parameter(default=12)]) -> None:
    return

app = Litestar(route_handlers=[query_default])

[globglarb]

Thanks for the workaround. I added the working schema snippet for completeness

...
 "paths": {
    "/query_default": {
      "get": {
        "summary": "QueryDefault",
        "operationId": "QueryDefaultQueryDefault",
        "parameters": [
          {
            "name": "foo",
            "in": "query",
            "schema": {
              "type": "integer",
              "default": 12
            },
            "required": false,
            "deprecated": false,
            "allowEmptyValue": false,
            "allowReserved": false
          }
        ],
...

[github-actions]

This issue has been closed in #3280. The change will be included in the upcoming patch release.

[github-actions]

A fix for this issue has been released in v2.8.0