Introduce a middleware that allows for HttpResponses to be thrown from inner utility functions, to avoid boilerplate in views

This commit is contained in:
Danielle McLean 2018-07-03 09:41:00 +10:00
parent 1d4be082cf
commit 7d17a92793
Firmato da: 00dani
ID Chiave GPG: 8EB789DDF3ABD240
4 ha cambiato i file con 22 aggiunte e 9 eliminazioni

Vedi File

@ -1,35 +1,35 @@
from typing import Union
from urllib.parse import urlparse
from django.contrib.sites.models import Site
from django.http import HttpResponse
from django.urls import resolve, Resolver404
from micropub.views import error
from lemoncurry.middleware import ResponseException
from .models import Entry
def from_url(url: str) -> Union[Entry, HttpResponse]:
def from_url(url: str) -> Entry:
domain = Site.objects.get_current().domain
if not url:
return error.bad_req('url parameter required')
raise ResponseException(error.bad_req('url parameter required'))
if '//' not in url:
url = '//' + url
parts = urlparse(url, scheme='https')
if parts.scheme not in ('http', 'https') or parts.netloc != domain:
return error.bad_req('url does not point to this site')
raise ResponseException(error.bad_req('url does not point to this site'))
try:
match = resolve(parts.path)
except Resolver404:
return error.bad_req('url does not point to a valid page on this site')
raise ResponseException(error.bad_req('url does not point to a valid page on this site'))
if match.view_name != 'entries:entry':
return error.bad_req('url does not point to an entry on this site')
raise ResponseException(error.bad_req('url does not point to an entry on this site'))
try:
entry = Entry.objects.get(pk=match.kwargs['id'])
except Entry.DoesNotExist:
return error.bad_req('url does not point to an existing entry')
raise ResponseException(error.bad_req('url does not point to an existing entry'))
return entry

14
lemoncurry/middleware.py Normal file
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@ -0,0 +1,14 @@
from django.http import HttpRequest, HttpResponse
from django.utils.deprecation import MiddlewareMixin
class ResponseException(Exception):
def __init__(self, response: HttpResponse) -> None:
self.response = response
class ResponseExceptionMiddleware(MiddlewareMixin):
def process_exception(self, request: HttpRequest, exception: Exception) -> HttpResponse:
if isinstance(exception, ResponseException):
return exception.response
raise exception

Vedi File

@ -118,6 +118,7 @@ MIDDLEWARE = [
'django.contrib.messages.middleware.MessageMiddleware',
'django.contrib.sites.middleware.CurrentSiteMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
'lemoncurry.middleware.ResponseExceptionMiddleware',
]
ROOT_URLCONF = 'lemoncurry.urls'

Vedi File

@ -17,8 +17,6 @@ def delete(request):
return error.unsupported_type(request.content_type)
url = normalise[request.content_type](request)
entry = from_url(url)
if isinstance(entry, HttpResponse):
return entry
if entry.author != request.token.user:
return error.forbid('entry belongs to another user')