"Create forum post" button on a rig page (#551)

* Add button for creating forum thread draft from event detail

TODO: Allow RIGS to ingest POST requests sent from the forum on new posts in RIG info to link up the forum thread

RE https://forum.nottinghamtec.co.uk/t/rigs-discourse-integration/15592/21

* Mockup webhook recieving view

* Correct method of CRSF exemption for webhook reciever

* Use f-strings correctly, not like a big dumb

* That was also dumb, fix that too

* Second shot at webhook reciever

* Oops

* >.<

* Third shot

* Try again at signing

* What if I gave it the right arguments. That might be a good start.

* More fiddling with auth

* Add debug print

* Okay, put that back where it was because I inavertently overloaded my import

Flashbacks to my java days...

* Different header access method

* Fix import, again

* Fix ommited json parsing wotsit

* Fix url

* Fix string index

* Correct template logic

* Allow manual adding/editing of URLs

* Filter by right flavour of event

* Amend event str conversion for consistency

* Oops

* Make migration

Will be squashed later

* Fix logic when creating events

* Squash migration

* Implement codedoctor suggestion

RIGS/models.py

@@ -308,6 +308,14 @@ class EventManager(models.Manager):
         return qs
 
 
+def validate_forum_url(value):
+    if not value:
+        return  # Required error is done the field
+    obj = urlparse(value)
+    if obj.hostname not in ('forum.nottinghamtec.co.uk'):
+        raise ValidationError('URL must point to a location on the TEC Forum')
+
+
 @reversion.register(follow=['items'])
 class Event(models.Model, RevisionMixin):
     # Done to make it much nicer on the database
@@ -357,6 +365,8 @@ class Event(models.Model, RevisionMixin):
     auth_request_at = models.DateTimeField(null=True, blank=True)
     auth_request_to = models.EmailField(blank=True, default='')
 
+    forum_url = models.URLField(default='', blank=True, validators=[validate_forum_url])
+
     @property
     def display_id(self):
         if self.pk:
@@ -505,7 +515,7 @@ class Event(models.Model, RevisionMixin):
         return reverse('event_detail', kwargs={'pk': self.pk})
 
     def __str__(self):
-        return f"{self.display_id}: {self.name}"
+        return f"{self.display_id} | {self.name}"
 
     def clean(self):
         errdict = {}