Populating sql table with foreign keys using django

Question

So im having some trouble inserting data into my sql database when using django. Setting up the tables aswell as populating them trough the admin page works perfectly fine but i have a scraper function that runts every 24h thats supposed to insert data.

from datetime import datetime
from .faceScraper import faceScraper as fc


def Dbpopulator():

    from ..models import Event

    [title_list, time_list, location_list, nation_list] = fc()
    print("scraped")
    for i in range(len(title_list)):
        
        e = Event()
        
        e.title = title_list[i]
        e.starttime = time_list[i][0]
        e.endtime = time_list[i][1]
        e.location = location_list[i]
        
        instance = e.save(commit=False)
        
        instance.nation = nation_list[i]
       
        instance.save()

The problem arises when im trying to set the nation which is a foreign key from the models file below.

from django.db import models

# Create your models here.


class Nation(models.Model):
    name = models.CharField(max_length=80, primary_key=True)

    description = models.TextField()

    Facebook = models.CharField(max_length=80, null=True, blank=True)

    def __str__(self):
        return self.name


class Event(models.Model):
    title = models.CharField(max_length=80, unique=True)

    starttime = models.DateTimeField(null=True, blank=True)

    endtime = models.DateTimeField(null=True, blank=True)

    nation = models.ForeignKey(
        Nation, on_delete=models.CASCADE, default=None, null=True, blank=True)

    location = models.CharField(max_length=80, null=True, blank=True)

    def __str__(self):
        return self.title

I have tried many different ways primarily just setting the e and saving like normal, aka cutting out all the instance and commit=false.

e.nation = nation_list[i]
e.save()

But it just wont work, i am also very certain that the database is already populated with nations which contains names that corresponds to what im trying to insert as i can see thoose on the admin page. All help apreciated!

Answer 1

You need to get the Nation instance first. If nation-list contains the names of the nations, you can get them like this:

e = Event()
...
e.nation = Nation.objects.get(name=nation_list[i])
e.save()

If you're not a 100% sure that provided name will match a Nation, you can use .filter(...).first() rather than .get(...) to avoid any crash.