Does anyone have or know of a recipe (sample code and/or instructions) on setting up many-to-many relationships between different Page models? If I have PersonPage and SitePage models, how do I connect the pages (a person can work at multiple sites and a site can have multiple people working there)?
Here's what I've found related to, but not directly on, this topic—
Wagtail docs: from a search for "many-to-many" the only hit is in the section on the taggit module (Recipes page).
Wagtail docs: the only reference to the ParentalManyToManyField is a demo of how it can be used to create M2Ms between pages and categories (Tutorial)
This 2015 post on M2M relationships in Wagtail (it's referenced in an SO 'answer' to basically the same question I'm asking here). Although it doesn't discuss page-page relationships the approach presented might be adapted to work. My modified imitation failed with various errors depending on how I tried to set up the InlinePanel call — but the sample code from the post fails in just the same ways, so either it wasn't tested or it's been made obsolete in 2.x.
class PersonPage(Page):
pass
PersonPage.content_panels = [
InlinePanel('ps_links', label='PS Links'),
]
class PersonSitePageLink():
spage = models.ForeignKey('SitePage', on_delete=models.SET_NULL, related_name='sites')
ppage = ParentalKey('PersonPage', related_name='ps_links', on_delete=models.SET_NULL,)
panels = [
FieldPanel('spage')
]
class SitePage(Page):
pass
class PlantPage(Page):
related_bugs = ParentalManyToManyField('BugPage', blank=True)
content_panels = Page.content_panels + [
FieldPanel('related_bugs'),
]
class BugPage(Page):
related_plants = ParentalManyToManyField('PlantPage', blank=True)
content_panels = Page.content_panels + [
FieldPanel('related_plants'),
]
I hope this helps, I took inspiration from this article about moving from ParentalManyToManyField
to a central model that 'links' each page from this AccordBox article.
It turns out that InlinePanel
does not fully support ParentalManyToManyField
, hence the issues you were running into.
I was able to implement a refined approach to your option one above and it should solve your problem.
A reminder that all Page
models already extend ClusterableModel
so there is no need to add that to any models you create.
models.Model
which will be the relation between these two page models.ParentalKey
each with a logical related_name
set that is the OTHER side of the relationship.panels
on this model as we will declare the panels individually via the panels
kwarg to InlinePanel
- see the InlinePanel docs.Page
's content_panels
has an InlinePanel
added that refers to the central relation model indirectly via that model's related_name
, adding the other side reference to PageChooserPanel
.
from modelcluster.fields import ParentalKey
from wagtail.admin.edit_handlers import FieldPanel, InlinePanel, PageChooserPanel
class PersonPageSitePageRelation(models.Model):
person = ParentalKey('app.PersonPage', on_delete=models.CASCADE, related_name='sites')
site = ParentalKey('app.SitePage', on_delete=models.CASCADE, related_name='people')
# Optional: some additional fields (e.g. 'note') for this relation
# Important: NOT setting any `panels` here, will be set individually for each 'direction'
class Meta:
unique_together = ('person', 'site')
class PersonPage(Page):
# ... fields (note: `sites` does NOT need to be declared as a field)
# Now we add an `InlinePanel` that will connect to the parental connection to PersonPageSitePageRelation via the related name `sites`, but the panels available will be the PersonPageSitePageRelation's field `site`
content_panels = Page.content_panels + [
# ... other FieldPanel etc
InlinePanel('sites', label='Related Sites', [PageChooserPanel('site')]),
]
class SitePage(Page):
# ... fields (note: `people` does NOT need to be declared as a field)
# Now we add an `InlinePanel` that will connect to the parental connection to PersonPageSitePageRelation via the related name `people`, but the panels available will be the PersonPageSitePageRelation's field `person`
content_panels = Page.content_panels + [
# ... other FieldPanel etc
InlinePanel('people', label='Related People', panels=[PageChooserPanel('person')]),
]
ParentalKey
comes from.