Middlewares

Middleware is a function that executes before the route handler in the application's request-response cycle. It has access to the request and response objects, as well as the next_fn() function, which passes control to the subsequent middleware. The next_fn() function is typically represented by the variable next_fn.

Python

from nestipy.common import Injectable

from nestipy.common import Request, Response
from nestipy.common import NestipyMiddleware
from nestipy.types_ import NextFn


@Injectable()
class LoggerMiddleware(NestipyMiddleware):
    async def use(self, req: Request, res: Response, next_fn: NextFn):
        print('Requesting ....')
        await next_fn()

Dependency injection

Nestipy middleware support dependency injection. Similar to providers and controllers, they can inject dependencies that are available within the same module.

Applying middleware

Nestipy apply middleware like the way Nestjs use. Modules that include middleware have to implement the NestipyModule.

app_module.py

from nestipy.dynamic_module import NestipyModule

from nestipy.common import Module
from nestipy.core import MiddlewareConsumer


@Module()
class AppModule(NestipyModule):
    def configure(self, consumer: MiddlewareConsumer):
        consumer.apply(LoggerMiddleware).for_route('cats')

Apply middleware for controller

We can apply middleware for controller and excludes some routes.

app_module.py

from nestipy.dynamic_module import NestipyModule

from nestipy.common import Module
from nestipy.core import MiddlewareConsumer


@Module()
class AppModule(NestipyModule):
    def configure(self, consumer: MiddlewareConsumer):
        consumer.apply(LoggerMiddleware).for_route(CatsController).excludes([])

Functional middleware

Python

from nestipy.common import Request, Response
from nestipy.types_ import NextFn


async def logger(req: Request, res: Response, next_fn: NextFn):
    print('Requesting ....')
    await next_fn()

And use it within the AppModule:

Python

consumer.apply(logger).for_route(CatsController).excludes([])

Global middleware

Python

from nestipy.core import NestipyFactory

app = NestipyFactory.create(AppModule)
app.use(logger)

Take a look here for an example.

Support us

Nestipy is a project released under the MIT license, meaning it's open source and freely available for use and modification. Its development thrives with the generous contributions of these fantastic individuals.