Sanic

After installing, Sanic has all the tools you need for a scalable, production-grade server—out of the box!

Including full TLS support.

from sanic import Sanic
from sanic.response import text

app = Sanic("MyHelloWorldApp")

@app.get("/")
async def hello_world(request):
    return text("Hello, world.")

sanic path.to.server:app
[2023-01-31 12:34:56 +0000] [999996] [INFO] Sanic v22.12.0
[2023-01-31 12:34:56 +0000] [999996] [INFO] Goin' Fast @ http://127.0.0.1:8000
[2023-01-31 12:34:56 +0000] [999996] [INFO] mode: production, single worker
[2023-01-31 12:34:56 +0000] [999996] [INFO] server: sanic, HTTP/1.1
[2023-01-31 12:34:56 +0000] [999996] [INFO] python: 3.10.9
[2023-01-31 12:34:56 +0000] [999996] [INFO] platform: SomeOS-9.8.7
[2023-01-31 12:34:56 +0000] [999996] [INFO] packages: sanic-routing==22.8.0
[2023-01-31 12:34:56 +0000] [999997] [INFO] Starting worker [999997]

Running Sanic with TLS enabled is as simple as passing it the file paths...

sanic path.to.server:app --cert=/path/to/bundle.crt --key=/path/to/privkey.pem

... or the a directory containing fullchain.pem and privkey.pem

sanic path.to.server:app --tls=/path/to/certs

Even better, while you are developing, let Sanic handle setting up local TLS certificates so you can access your site over TLS at https://localhost:8443

sanic path.to.server:app --dev --auto-tls

Up and running with websockets in no time using the websockets package.

from sanic import Request, Websocket

@app.websocket("/feed")
async def feed(request: Request, ws: Websocket):
    async for msg in ws:
        await ws.send(msg)

Serving static files is of course intuitive and easy. Just name an endpoint and either a file or directory that should be served.

app.static("/", "/path/to/index.html")
app.static("/uploads/", "/path/to/uploads/")

Moreover, serving a directory has two additional features: automatically serving an index, and automatically serving a file browser.

Sanic can automatically serve index.html (or any other named file) as an index page in a directory or its subdirectories.

app.static(
    "/uploads/",
    "/path/to/uploads/",
    index="index.html"
)

And/or, setup Sanic to display a file browser.

app.static(
    "/uploads/",
    "/path/to/uploads/",
    directory_view=True
)

Beginning or ending a route with functionality is as simple as adding a decorator.

@app.on_request
async def add_key(request):
    request.ctx.foo = "bar"

@app.on_response
async def custom_banner(request, response):
    response.headers["X-Foo"] = request.ctx.foo

Same with server events.

@app.before_server_start
async def setup_db(app):
    app.ctx.db_pool = await db_setup()

@app.after_server_stop
async def setup_db(app):
    await app.ctx.db_pool.shutdown()

But, Sanic also allows you to tie into a bunch of built-in events (called signals), or create and dispatch your own.

@app.signal("http.lifecycle.complete")  # built-in
async def my_signal_handler(conn_info):
    print("Connection has been closed")

@app.signal("something.happened.ohmy")  # custom
async def my_signal_handler():
    print("something happened")

await app.dispatch("something.happened.ohmy")

Raising errors will intuitively result in proper HTTP errors:

raise sanic.exceptions.NotFound  # Automatically responds with HTTP 404

Or, make your own:

from sanic.exceptions import SanicException

class TeapotError(SanicException):
    status_code = 418
    message = "Sorry, I cannot brew coffee"

raise TeapotError

And, when an error does happen, Sanic's beautiful DEV mode error page will help you drill down to the bug quickly.

Regardless, Sanic comes with an algorithm that attempts to respond with HTML, JSON, or text-based errors as appropriate. Don't worry, it is super easy to setup and customize your error handling to your exact needs.

Check in on your live, running applications (whether local or remote).

sanic inspect      

┌─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│                                                        Sanic                                                        │
│                                          Inspecting @ http://localhost:6457                                         │
├───────────────────────┬─────────────────────────────────────────────────────────────────────────────────────────────┤
│                       │     mode: production, single worker                                                         │
│     ▄███ █████ ██     │   server: unknown                                                                           │
│    ██                 │   python: 3.10.9                                                                            │
│     ▀███████ ███▄     │ platform: SomeOS-9.8.7
│                 ██    │ packages: sanic==22.12.0, sanic-routing==22.8.0, sanic-testing==22.12.0, sanic-ext==22.12.0 │
│    ████ ████████▀     │                                                                                             │
│                       │                                                                                             │
│ Build Fast. Run Fast. │                                                                                             │
└───────────────────────┴─────────────────────────────────────────────────────────────────────────────────────────────┘

Sanic-Main
    pid: 999996

Sanic-Server-0-0
    server: True
    state: ACKED
    pid: 999997
    start_at: 2023-01-31T12:34:56.00000+00:00
    starts: 1

Sanic-Inspector-0
    server: False
    state: STARTED
    pid: 999998
    start_at: 2023-01-31T12:34:56.00000+00:00
    starts: 1

And, issue commands like reload, shutdown, scale...

sanic inspect scale 4

... or even create your own!

sanic inspect migrations

In addition to the tools that Sanic comes with, the officially supported Sanic Extensions provides lots of extra goodies to make development easier.

• CORS protection
• Template rendering with Jinja
• Dependency injection into route handlers
• OpenAPI documentation with Redoc and/or Swagger
• Predefined, endpoint-specific response serializers
• Request query arguments and body input validation
• Auto create HEAD, OPTIONS, and TRACE endpoints
• Live health monitor

Sanic is built for building.

From the moment it is installed, Sanic includes helpful tools to help the developer get their job done.

• One server - Develop locally in DEV mode on the same server that will run your PRODUCTION application
• Auto reload - Reload running applications every time you save a Python file, but also auto-reload on any arbitrary directory like HTML template directories
• Debugging tools - Super helpful (and beautiful) error pages that help you traverse the trace stack easily
• Auto TLS - Running a localhost website with https can be difficult, Sanic makes it easy
• Streamlined testing - Built-in testing capabilities, making it easier for developers to create and run tests, ensuring the quality and reliability of their services
• Modern Python - Thoughtful use of type hints to help the developer IDE experience