fastapi-versioning

api versioning for fastapi web applications

Examples

from fastapi import FastAPI
from fastapi_versioning import VersionedFastAPI, version

app = FastAPI(title='My App')

@app.get('/greet')
@version(1, 0)
def greet():
  return 'Hello'

@app.get('/greet')
@version(1, 1)
def greet():
  return 'Hi'

app = VersionedFastAPI(app)

this will generate two endpoints:

/v1_0/greet
/v1_1/greet

as well as:

/docs
/v1_0/docs
/v1_1/docs
/v1_0/openapi.json
/v1_1/openapi.json

Try it out:

pip install pipenv
pipenv install --dev
pipenv run uvicorn example.app:app

Usage without minor version

from fastapi import FastAPI
from fastapi_versioning import VersionedFastAPI, version

app = FastAPI(title='My App')

@app.get('/greet')
@version(1)
def greet():
  return 'Hello'

@app.get('/greet')
@version(2)
def greet():
  return 'Hi'

app = VersionedFastAPI(app,
    version_format='{major}',
    prefix_format='/v{major}')

this will generate two endpoints:

/v1/greet
/v2/greet

as well as:

/docs
/v1/docs
/v2/docs
/v1/openapi.json
/v2/openapi.json

Extra FastAPI constructor arguments

It's important to note that only the title from the original FastAPI will be provided to the VersionedAPI app. If you have any middleware, event handlers etc these arguments will also need to be provided to the VersionedAPI function call, as in the example below

from fastapi import FastAPI, Request
from fastapi_versioning import VersionedFastAPI, version
from starlette.middleware import Middleware
from starlette.middleware.sessions import SessionMiddleware

app = FastAPI(
    title='My App',
    description='Greet uses with a nice message',
    middleware=[
        Middleware(SessionMiddleware, secret_key='mysecretkey')
    ]
)

@app.get('/greet')
@version(1)
def greet(request: Request):
    request.session['last_version_used'] = 1
    return 'Hello'

@app.get('/greet')
@version(2)
def greet(request: Request):
    request.session['last_version_used'] = 2
    return 'Hi'

@app.get('/version')
def last_version(request: Request):
    return f'Your last greeting was sent from version {request.session["last_version_used"]}'

app = VersionedFastAPI(app,
    version_format='{major}',
    prefix_format='/v{major}',
    description='Greet uses with a nice message',
    middleware=[
        Middleware(SessionMiddleware, secret_key='mysecretkey')
    ]
)