OpenAPI Docs

fastapi-filters uses CSV-separated values for list parameters (e.g., field[in]=a,b,c). By default, Swagger UI may render these incorrectly with explode: true, generating separate query parameters for each value.

Fixing Swagger UI

Use fix_docs() to patch the OpenAPI schema so CSV parameters render correctly:

from fastapi import FastAPI

from fastapi_filters.docs import fix_docs

app = FastAPI()

fix_docs(app)

This sets explode: false on the relevant parameters in the generated OpenAPI schema, so Swagger UI displays a single input field for comma-separated values.

Tip

Call fix_docs(app) right after creating your FastAPI instance, before defining any routes.