basic.py

from fastapi import FastAPI, HTTPException, Depends, Request
from fastapi.responses import JSONResponse
from fastapi_jwt_auth import AuthJWT
from fastapi_jwt_auth.exceptions import AuthJWTException
from pydantic import BaseModel

app = FastAPI()

class User(BaseModel):
    username: str
    password: str

# in production you can use Settings management
# from pydantic to get secret key from .env
class Settings(BaseModel):
    authjwt_secret_key: str = "secret"

# callback to get your configuration
@AuthJWT.load_config
def get_config():
    return Settings()

# exception handler for authjwt
# in production, you can tweak performance using orjson response
@app.exception_handler(AuthJWTException)
def authjwt_exception_handler(request: Request, exc: AuthJWTException):
    return JSONResponse(
        status_code=exc.status_code,
        content={"detail": exc.message}
    )

# provide a method to create access tokens. The create_access_token()
# function is used to actually generate the token to use authorization
# later in endpoint protected
@app.post('/login')
def login(user: User, Authorize: AuthJWT = Depends()):
    if user.username != "test" or user.password != "test":
        raise HTTPException(status_code=401,detail="Bad username or password")

    # subject identifier for who this token is for example id or username from database
    access_token = Authorize.create_access_token(subject=user.username)
    return {"access_token": access_token}

# protect endpoint with function jwt_required(), which requires
# a valid access token in the request headers to access.
@app.get('/user')
def user(Authorize: AuthJWT = Depends()):
    Authorize.jwt_required()

    current_user = Authorize.get_jwt_subject()
    return {"user": current_user}