django/tests/middleware_exceptions/middleware.py

from asgiref.sync import iscoroutinefunction, markcoroutinefunction

from django.http import Http404, HttpResponse
from django.template import engines
from django.template.response import TemplateResponse
from django.utils.decorators import (
    async_only_middleware,
    sync_and_async_middleware,
    sync_only_middleware,
)

log = []


class BaseMiddleware:
    def __init__(self, get_response):
        self.get_response = get_response
        if iscoroutinefunction(self.get_response):
            markcoroutinefunction(self)

    def __call__(self, request):
        return self.get_response(request)


class ProcessExceptionMiddleware(BaseMiddleware):
    def process_exception(self, request, exception):
        return HttpResponse("Exception caught")


@async_only_middleware
class AsyncProcessExceptionMiddleware(BaseMiddleware):
    async def process_exception(self, request, exception):
        return HttpResponse("Exception caught")


class ProcessExceptionLogMiddleware(BaseMiddleware):
    def process_exception(self, request, exception):
        log.append("process-exception")


class ProcessExceptionExcMiddleware(BaseMiddleware):
    def process_exception(self, request, exception):
        raise Exception("from process-exception")


class ProcessViewMiddleware(BaseMiddleware):
    def process_view(self, request, view_func, view_args, view_kwargs):
        return HttpResponse("Processed view %s" % view_func.__name__)


@async_only_middleware
class AsyncProcessViewMiddleware(BaseMiddleware):
    async def process_view(self, request, view_func, view_args, view_kwargs):
        return HttpResponse("Processed view %s" % view_func.__name__)


class ProcessViewNoneMiddleware(BaseMiddleware):
    def process_view(self, request, view_func, view_args, view_kwargs):
        log.append("processed view %s" % view_func.__name__)
        return None


class ProcessViewTemplateResponseMiddleware(BaseMiddleware):
    def process_view(self, request, view_func, view_args, view_kwargs):
        template = engines["django"].from_string(
            "Processed view {{ view }}{% for m in mw %}\n{{ m }}{% endfor %}"
        )
        return TemplateResponse(
            request,
            template,
            {"mw": [self.__class__.__name__], "view": view_func.__name__},
        )


class TemplateResponseMiddleware(BaseMiddleware):
    def process_template_response(self, request, response):
        response.context_data["mw"].append(self.__class__.__name__)
        return response


@async_only_middleware
class AsyncTemplateResponseMiddleware(BaseMiddleware):
    async def process_template_response(self, request, response):
        response.context_data["mw"].append(self.__class__.__name__)
        return response


class LogMiddleware(BaseMiddleware):
    def __call__(self, request):
        response = self.get_response(request)
        log.append((response.status_code, response.content))
        return response


class NoTemplateResponseMiddleware(BaseMiddleware):
    def process_template_response(self, request, response):
        return None


@async_only_middleware
class AsyncNoTemplateResponseMiddleware(BaseMiddleware):
    async def process_template_response(self, request, response):
        return None


class NotFoundMiddleware(BaseMiddleware):
    def __call__(self, request):
        raise Http404("not found")


class PaymentMiddleware(BaseMiddleware):
    def __call__(self, request):
        response = self.get_response(request)
        response.status_code = 402
        return response


@async_only_middleware
def async_payment_middleware(get_response):
    async def middleware(request):
        response = await get_response(request)
        response.status_code = 402
        return response

    return middleware


@sync_and_async_middleware
class SyncAndAsyncMiddleware(BaseMiddleware):
    pass


@sync_only_middleware
class DecoratedPaymentMiddleware(PaymentMiddleware):
    pass


class NotSyncOrAsyncMiddleware(BaseMiddleware):
    """Middleware that is deliberately neither sync or async."""

    sync_capable = False
    async_capable = False

    def __call__(self, request):
        return self.get_response(request)