# About FastAPI versions

**FastAPI** is already being used in production in many applications and systems. And the test coverage is kept at 100%. But its development is still moving quickly.

New features are added frequently, bugs are fixed regularly, and the code is still continuously improving.

<div class="termy">

```console
$ pip install websockets

---> 100%
```

</div>

## WebSockets client

### In production

In your production system, you probably have a frontend created with a modern framework like React, Vue.js or Angular.

And to communicate using WebSockets with your backend you would probably use your frontend's utilities.

# The mode of Lasta Di's smart-deploy, should be cool in production (e.g. hot, cool, warm)
lasta_di.smart.deploy.mode = warm

# Is development environment here? (used for various purpose, you should set false if unknown)
development.here = true

# The title of environment (e.g. local or integration or production)
environment.title = Local Development

For production you would use `fastapi run` instead. 🚀

Internally, **FastAPI CLI** uses <a href="https://www.uvicorn.org" class="external-link" target="_blank">Uvicorn</a>, a high-performance, production-ready, ASGI server. 😎

## `fastapi dev`

Running `fastapi dev` initiates development mode.

- Test all upgrades in a lower environment (DEV, QA, UAT) before applying to production. Performing blind upgrades in production environments carries significant risk.
- Read the release notes for MinIO *before* performing any upgrade, there is no forced requirement to upgrade to latest release upon every release. Some release may not be relevant to your setup, avoid upgrading production environments unnecessarily.

# use single binary and filesystem storage for test
# do not use in production
loki:
  useTestSchema: true
  auth_enabled: false
  commonConfig:
    replication_factor: 1
  storage:
    type: 'filesystem'
test:
  enabled: false
lokiCanary:
  enabled: false
monitoring:
  dashboards:
    enabled: false
  rules:
    enabled: false
    alerting: false
  serviceMonitor:
    enabled: false
    metricsInstance:

from fastapi import FastAPI, Request

app = FastAPI(
    servers=[
        {"url": "https://stag.example.com", "description": "Staging environment"},
        {"url": "https://prod.example.com", "description": "Production environment"},
    ],
    root_path="/api/v1",
)


@app.get("/app")
def read_main(request: Request):

from pydantic import BaseModel, EmailStr

app = FastAPI()


class UserIn(BaseModel):
    username: str
    password: str
    email: EmailStr
    full_name: Union[str, None] = None


# Don't do this in production!
@app.post("/user/")
async def create_user(user: UserIn) -> UserIn:

    * **Concis** : Minimise la duplication de code. Plusieurs fonctionnalités à chaque déclaration de paramètre.
    * **Robuste** : Obtenez du code prêt pour être utilisé en production. Avec de la documentation automatique interactive.

 │                          │
 ╰──────────────────────────╯

<font color="#3465A4">INFO    </font> Using import string <font color="#8AE234"><b>main:app</b></font>

 <font color="#4E9A06">╭─────────── FastAPI CLI - Production mode ───────────╮</font>
 <font color="#4E9A06">│                                                     │</font>
 <font color="#4E9A06">│  Serving at: http://0.0.0.0:8000                    │</font>