Скачать или смотреть Creating Custom Filters in Django with django-filters

Learn how to create `custom filter sets` in Django using django-filters to enhance your application's querying capabilities.
---
This video is based on the question https://stackoverflow.com/q/72319516/ asked by the user 'Jeet Patel' ( https://stackoverflow.com/u/7790226/ ) and on the answer https://stackoverflow.com/a/72321206/ provided by the user 'Metalgear' ( https://stackoverflow.com/u/12965562/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Creating custom fields with django-filters

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Creating Custom Filters in Django with django-filters

In the world of web development, efficiently retrieving data from databases is crucial for building responsive applications. When working with Django, a powerful web framework, developers often face the need for advanced filtering options particularly when it comes to foreign key relationships. This guide will guide you through the process of creating custom filters using the django-filters package, specifically focusing on filtering foreign key fields with multiple values.

The Challenge: Adding Custom Filters

Imagine you have a Django model, YachtGeneralInfo, that contains a foreign key to another model, YachtTypes. You encounter a scenario where you want to filter the YachtGeneralInfo queryset based on multiple YachtTypes. The conventional approach would be to conduct filtering directly in the queryset like this:

[[See Video to Reveal this Text or Code Snippet]]

While this solution works, it's often better practice to implement a more organized approach using django-filters, especially if you need to handle more complex filtering scenarios across your application.

The Solution: Custom Filter Set

Step 1: Create Your Custom Filter Set

To create a custom filtering mechanism, you'll need to define a filter set that can handle your specific conditions. Here’s how you can do this:

[[See Video to Reveal this Text or Code Snippet]]

Breakdown of the Custom Filter Set

Importing Required Modules: First, ensure you import django_filters and json.

Creating the Filter Set: Extend django_filters.FilterSet to create your custom filter.

Defining the Filter: In this case, a CharFilter is created that utilizes a custom method called filter_type_in.

Filtering Logic: In the filter_type_in method, check if the provided value is not empty, then parse the JSON to get an array of IDs and finally filter the queryset accordingly.

Step 2: Integrate the Custom Filter Set into Your View

Once your custom filter set is defined, you will need to integrate it into the YachtGeneralInfoView. Here’s how you can do this:

[[See Video to Reveal this Text or Code Snippet]]

Combining Various Filters

With the custom filter set in place, you can now easily filter YachtGeneralInfo by specifying multiple types in your queries. For example, through a GET request, you might specify the filter condition like this:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

Creating custom filter sets in Django using django-filters not only enhances the readability and organization of your code but also provides more flexibility in handling complex query requirements. By following the steps outlined in this blog, you can effectively implement custom filters for your models, making data retrieval much more dynamic and powerful.

Now that you understand the basics of setting up custom filters, you can apply this knowledge to enhance your Django applications further. Happy coding!