81 lines
2.5 KiB
Python
81 lines
2.5 KiB
Python
"""
|
|
utils.converter: Custom URL converters to match patterns in @app.route()
|
|
|
|
The Flask documentation is elusive on this topic. To add a new converter,
|
|
proceed as follows:
|
|
|
|
1. Define a new converter class.
|
|
2. Set the [regex] attribute to decide which portion of the URL will be
|
|
considered for conversion (apparently the default is everything until next
|
|
slash or end of string).
|
|
3. Define the to_python() and to_url() methods to actually convert.
|
|
4. Add the class to __all__ at the bottom of this file.
|
|
5. In app/__init__.py, add a dictionary entry to [app.url_map.converters].
|
|
|
|
For more information, see the Werkzeug documentation:
|
|
<https://werkzeug.palletsprojects.com/en/0.15.x/routing/#custom-converters>
|
|
"""
|
|
|
|
from werkzeug.routing import BaseConverter, ValidationError
|
|
from app.models.forum import Forum
|
|
from app.models.topic import Topic
|
|
from slugify import slugify
|
|
|
|
|
|
class ForumConverter(BaseConverter):
|
|
|
|
# This regex will decide which portion of the URL is matched by the curtom
|
|
# converter. By default, slashes are not included, so we must add them.
|
|
regex = r'[a-z/]+'
|
|
|
|
def to_python(self, url):
|
|
url = '/' + url
|
|
f = Forum.query.filter_by(url=url).first()
|
|
if f is None:
|
|
raise ValidationError(f"ForumConverter: no forum with url {url}")
|
|
return f
|
|
|
|
def to_url(self, forum):
|
|
return forum.url[1:]
|
|
|
|
class PageConverter(BaseConverter):
|
|
|
|
# Matches integers for the topic number, then either nothing, a page
|
|
# number, a slug, or a page number followed by a slug
|
|
regex = r'(\d+)(?:/(\d+)|/fin)?(?:/[\w-]+)?'
|
|
object = None
|
|
|
|
def to_python(self, url):
|
|
tid, *args = url.split('/')
|
|
tid = int(tid)
|
|
|
|
if len(args) == 0:
|
|
page = 1
|
|
elif args[0] == "fin":
|
|
page = -1
|
|
else:
|
|
# The argument is considered to be a slug if it's not "last" and it
|
|
# doesn't convert to an int
|
|
try:
|
|
page = int(args[0])
|
|
except ValueError:
|
|
page = 1
|
|
|
|
t = self.object.query.filter_by(id=tid).first()
|
|
if t is None:
|
|
raise Exception(f"BaseConverter: no object with id {url}")
|
|
|
|
return (t, page)
|
|
|
|
def to_url(self, object_and_page):
|
|
o, page = object_and_page
|
|
page = str(page) if page != -1 else "fin"
|
|
slug = slugify(o.title)
|
|
return f'{o.id}/{page}/{slug}'
|
|
|
|
class TopicPageConverter(PageConverter):
|
|
object = Topic
|
|
|
|
# Export only the converter classes
|
|
__all__ = "ForumConverter TopicPageConverter".split()
|