fastapi-versioning

api versioning for fastapi web applications

Installation

pip install fastapi-versioning

Examples

fromfastapiimportFastAPIfromfastapi_versioningimportVersionedFastAPI, versionapp=FastAPI(title="My App")
@app.get("/greet")@version(1, 0)defgreet_with_hello():
return"Hello"@app.get("/greet")@version(1, 1)defgreet_with_hi():
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

There's also the possibility of adding a set of additional endpoints that redirect the most recent API version. To do that make the argument enable_latest true:

app=VersionedFastAPI(app, enable_latest=True)

this will generate the following additional endpoints:

/latest/greet
/latest/docs
/latest/openapi.json

In this example, /latest endpoints will reflect the same data as /v1.1.

Try it out:

pip install pipenv
pipenv install --dev
pipenv run uvicorn example.annotation.app:app
# pipenv run uvicorn example.folder_name.app:app

Usage without minor version

fromfastapiimportFastAPIfromfastapi_versioningimportVersionedFastAPI, versionapp=FastAPI(title='My App')
@app.get('/greet')@version(1)defgreet():
return'Hello'@app.get('/greet')@version(2)defgreet():
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

fromfastapiimportFastAPI, Requestfromfastapi_versioningimportVersionedFastAPI, versionfromstarlette.middlewareimportMiddlewarefromstarlette.middleware.sessionsimportSessionMiddlewareapp=FastAPI(
title='My App',
description='Greet uses with a nice message',
middleware=[
Middleware(SessionMiddleware, secret_key='mysecretkey')
]
)
@app.get('/greet')@version(1)defgreet(request: Request):
request.session['last_version_used'] =1return'Hello'@app.get('/greet')@version(2)defgreet(request: Request):
request.session['last_version_used'] =2return'Hi'@app.get('/version')deflast_version(request: Request):
returnf'Your last greeting was sent from version {request.session["last_version_used"]}'app=VersionedFastAPI(app,
version_format='{major}',
prefix_format='/v{major}',
description='Greet users with a nice message',
middleware=[
Middleware(SessionMiddleware, secret_key='mysecretkey')
]
)