FilterMapBackend

Table Of Content

• Introduction
• Installation
• Usage

Introduction

FilterBackend which takes mapping of query params to field name.

It takes the query_param to filter map and enables filter option in list view.

Installation

Install drf-filtermapbackend using

pip install drf-filtermapbackend

Then include filter_map in your installed apps

INSTALLED_APPS = [
    ...,
    'rest_framework',
    'filter_map',
    ...
]

Usage

You can use FilterMapBackend by adding it to your filter backends and setting filter_map attribute. For example

from rest_framework.viewsets import ModelViewSet
from filter_map.backends import FilterMapBackend

class ProfileViewSet(ModelViewSet):
    """
    Consider Profile Model has user FK,
    """
    queryset = ...
    serializer_class = ...
    filter_backends = (FilterMapBackend,)
    filter_map = {
        # plain map
        'first_name': 'user__first_name',
        
        # used with lte operator
        'joined_before': 'date_joined__date__lte',
        
        # also supports separate field name and operator 
        'last_name': ('user__last_name', 'iexact'),
    }
    

You can also define get_filter_map method to return the filter map. This will allow you to change filter_map in runtime. Here's an example

from rest_framework.viewsets import ModelViewSet
from filter_map.backends import FilterMapBackend

class ProfileViewSet(ModelViewSet):
    """
    Consider Profile Model has user FK,
    """
    queryset = ...
    serializer_class = ...
    filter_backends = (FilterMapBackend,)
    
    def get_filter_map(self):
        # Disable joined_before filter for non staff users
        if self.request.user.is_authenticated and self.request.user.is_staff:
            return {
                'first_name': 'user__first_name',
                'joined_before': 'date_joined__date__lte',
                'last_name': ('user__last_name', 'iexact'),
            }
        else:
            return {
                'first_name': 'user__first_name',
                'last_name': ('user__last_name', 'iexact'),
            }