How to deal with circular relationship in Django models?

I'm trying to write a basic DB to offer my photographs. It seemed so simple, but I just can't wrap my head around this, despite thinking for a couple of weeks. I'm trying to combine multiple models that link to each other.

Photo: Files with some stored data
Person: Data about a person that appears in a photo / has mad a Quote
Quote: Something a Person has said and needs to be attached to Photos
(the quote does not belong to all photos of that person, but rather a specific set)
Offer: An overview that has all the quotes with one Photo as a thumbnail and all the Photos
(some photos might have the same quote, but it should only appear once)

As a mockup and because people here really love to see some code first I made this:

class Quote:
    person = models.ForeignKey("Person")
    photos = models.ManyToManyField("Photo")
    
class Person:
    photo = models.ForeignKey("Photo")
    
class Photo:
    pass
    
class Offer:
    quotes = models.ManyToManyField("Quote")
    photos = models.ManyToManyField("Photo")

Please take the code above as an illustration, because I already don't know how to tackle this. I tried multiple different versions, but there is always some case that doesn't get covered. In the above example the problem is: Person and Quote are independently attached to Photos. But there can't be a Quote without that Person being in there. So some information is doubled and might disagree. I also tried to using "through=" to bring People and Quotes together, but then ran into other problems.

Can you recommend any good tutorials or give me a hint how to deal with these kind of 'messy' relationships?

Thank you, Michael

Back to Top