how to add multiple autocomplete in django admin page

Question

I am using built in function to build autocomplete for many fields: https://docs.djangoproject.com/en/2.0/ref/contrib/admin/#django.contrib.admin.ModelAdmin.autocomplete_fields

I have following model:

 class Ipaddress(models.Model):
        ipaddress=models.CharField(max_length=20)
        slug = models.SlugField(unique=True)
        machinename=models.CharField(max_length=500)
        user=models.CharField(max_length=200)
        department= models.ForeignKey('Department',on_delete=models.CASCADE,default='Empty')
        location= models.ForeignKey('Location', on_delete=models.CASCADE)
        updated = models.DateField("Date Updated",null=True)
        note =models.TextField()

    def __str__(self):
        return self.ipaddress[:50]

class Department(models.Model):
    name= models.CharField(max_length=100, unique=True)
    def __str__(self):
        return self.name[:50] 

class Location(models.Model):
    description= models.CharField(max_length=100, unique=True)
    def __str__(self):
        return self.description[:50] 

The admin page is here:

from django.contrib import admin
from pages.models import  Ipaddress, DeviceGroup, Location,Department,
from django_admin_listfilter_dropdown.filters import DropdownFilter, RelatedDropdownFilter

class IpaddressAdmin(admin.ModelAdmin):
        prepopulated_fields = {'slug': ('ipaddress',)}

        search_fields = ['ipaddress']
        autocomplete_fields = ['department',]

        list_display = ('ipaddress', 'machinename', 'user', 'department','location','updated',)
        list_filter = (
        ('user', DropdownFilter),
        ('department', RelatedDropdownFilter),
        ('location', RelatedDropdownFilter),

    )

If i change the autocomplete_fields = ['location',] it works but it does not work when i try to change it department. Also i want to have autocomplete for both department and location at the same time.

The error i am seeing is when i set autocomplete_fields = ['department',]

ERRORS:<class 'pages.admin.IpaddressAdmin'>: (admin.E040) ModelAdmin must define    
"search_fields", because it's referenced by 
IpaddressAdmin.autocomplete_fields.

Any idea how to fix this error I want to some thing like this:

 autocomplete_fields = ['department', 'location','user',]

Answer 1

As per the documentation that you have referenced in your link here

You must define search_fields on the related object’s ModelAdmin because the autocomplete search uses it.

What this means, in your case and also from the error that you are getting is you need to define your search_fields on the related object ( in your case Department and Location ModelAdmin classes, because the autocomplete search uses it).

So, it would be something like this.

class DepartmentAdmin(admin.ModelAdmin):
    search_fields = ['name']

class LocationAdmin(admin.ModelAdmin):
    search_fields = ['description']

Your autocomplete_fields on your IPAddressAdmin can then be like this.

 autocomplete_fields = ['department', 'location',]