Django Complex Filter

A powerful and flexible declarative filter for Django ORM that enables complex query construction through a simple JSON-based API. Perfect for building advanced filtering capabilities in your Django REST Framework applications.

Features

• Advanced Filtering: Complex AND/OR operations with nested conditions
• Declarative Syntax: Simple JSON-based query structure
• Dynamic Values: Support for computed values and server-side calculations
• Related Model Queries: Efficient subquery handling for related models
• Extensible: Easy to add custom operators and value functions
• Type Safe: Built-in operator validation
• DRF Integration: Seamless integration with Django REST Framework

Installation

pip install drf-complex-filter

Quick Start

1. Add ComplexQueryFilter to your ViewSet:

from drf_complex_filter.filters import ComplexQueryFilter

class UserViewSet(ModelViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer
    filter_backends = [ComplexQueryFilter]

2. Make API requests with complex filters:

# Simple equality filter
GET /users?filters={"type":"operator","data":{"attribute":"first_name","operator":"=","value":"John"}}

# Complex AND condition
GET /users?filters={"type":"and","data":[
    {"type":"operator","data":{"attribute":"age","operator":">","value":18}},
    {"type":"operator","data":{"attribute":"is_active","operator":"=","value":true}}
]}

Filter Types

1. Simple Operator

{
    "type": "operator",
    "data": {
        "attribute": "field_name",
        "operator": "=",
        "value": "value_to_compare"
    }
}

2. AND Operator

{
    "type": "and",
    "data": [
        # List of operators to combine with AND
    ]
}

3. OR Operator

{
    "type": "or",
    "data": [
        # List of operators to combine with OR
    ]
}

Available Operators

Operator	Description	Symbol
Is	Equality	=
Is not	Inequality	!=
Contains	Case-insensitive contains	*
Not contains	Case-insensitive not contains	!
Greater	Greater than	>
Greater or equal	Greater than or equal	>=
Less	Less than	<
Less or equal	Less than or equal	<=
In	Value in list	in
Not in	Value not in list	not_in
Current user	Current authenticated user	me
Not current user	Not current authenticated user	not_me

Advanced Features

Custom Operators

1. Create your operator class:

class CustomOperators:
    def get_operators(self):
        return {
            "custom_op": lambda f, v, r, m: Q(**{f"{f}__custom": v}),
        }

2. Register in settings:

COMPLEX_FILTER_SETTINGS = {
    "COMPARISON_CLASSES": [
        "drf_complex_filter.comparisons.CommonComparison",
        "path.to.CustomOperators",
    ],
}

Dynamic Values

1. Create value functions:

class CustomFunctions:
    def get_functions(self):
        return {
            "current_time": lambda request, model: timezone.now(),
        }

2. Register in settings:

COMPLEX_FILTER_SETTINGS = {
    "VALUE_FUNCTIONS": [
        "drf_complex_filter.functions.DateFunctions",
        "path.to.CustomFunctions",
    ],
}

3. Use in filters:

{
    "type": "operator",
    "data": {
        "attribute": "created_at",
        "operator": ">",
        "value": {
            "func": "current_time",
            "kwargs": {}
        }
    }
}

Related Model Queries

Use ModelName___ prefix for efficient subqueries:

{
    "type": "operator",
    "data": {
        "attribute": "Profile___is_verified",
        "operator": "=",
        "value": true
    }
}

Requirements

• Python >= 3.6
• Django >= 3.0.0
• Django REST Framework

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.