Interactive OpenAPI 3.0

🛠 OpenAPI 3.0 & Pydantic Schema Generation

RustAPI provides automatic, 100% FastAPI-compatible OpenAPI 3.0.0 specification generation served at /openapi.json and rendered interactively in Swagger UI at /docs and Redoc at /redoc.

✨ Architectural Advantages

Zero-Copy Ref Resolution: Pydantic models automatically register schemas in components["schemas"] and link via $ref.
Nested Hoisting: Pydantic v2 $defs nested schemas are automatically hoisted to components["schemas"].
Standard 422 Payload: Standardized HTTPValidationError and ValidationError schemas on all endpoints.
Interactive Swagger Pickers: Single and multi-file array upload pickers for Swagger UI.
Dependency Isolation: Depends(...) objects are excluded from query parameters without crashing JSON serializers.

Schema Resolution

📦 Pydantic Request & Response Models

Decorate route handlers with response_model or use Pydantic type annotations for request body parameters:

from pydantic import BaseModel
from rustapi import FastAPI

app = FastAPI(title="Product Catalog API")

class ProductIn(BaseModel):
    name: str
    price: float

class ProductOut(BaseModel):
    id: int
    name: str
    price: float

@app.post("/products", response_model=ProductOut, status_code=201)
def create_product(product: ProductIn):
    return ProductOut(id=1, name=product.name, price=product.price)

Structured Errors

⚠️ Validation Error Schemas (422)

When query, path, or request body payloads fail type validation, RustAPI yields structured 422 Unprocessable Entity JSON matching FastAPI:

{
  "detail": [
    {
      "loc": ["query", "item_id"],
      "msg": "invalid integer value",
      "type": "type_error.integer"
    }
  ]
}

Multipart Form-Data

📁 UploadFile & Form Schemas

from typing import List
from rustapi import FastAPI, File, Form, UploadFile

app = FastAPI()

@app.post("/upload")
def upload_single(file: UploadFile = File(...), note: str = Form("")):
    return {"filename": file.filename, "note": note}

@app.post("/upload-batch")
def upload_multi(files: List[UploadFile] = File(...)):
    return {"count": len(files)}

Standalone Generator

🔧 Standalone OpenAPI Utility

from rustapi.openapi.utils import get_openapi

spec = get_openapi(
    title="Custom Microservice",
    version="1.0.0",
    description="Standalone OpenAPI 3.0 spec generator",
)