FastAPI Adapter

The FastAPI adapter exposes your pRPC procedures at POST /rpc on a FastAPI app.

Installation

uv add prpc prpc-fastapi

Basic Setup

from fastapi import FastAPI
from prpc import rpc
from prpc_fastapi import mount_fastapi

app = FastAPI()

@rpc
def add(a: int, b: int) -> int:
    return a + b

mount_fastapi(app)

This registers add in the global registry and mounts a POST /rpc endpoint that forwards requests to pRPC.

How It Works

• @rpc registers functions in the default registry.
• mount_fastapi(app) adds a FastAPI route:
  • path: /rpc
  • method: POST
  • body: JSON-RPC request payload

The adapter calls handle_request(payload) from prpc, then returns the JSON-RPC response.