Extending OpenWISP IPAM

Note

This page is for developers who want to customize or extend OpenWISP IPAM, whether for bug fixes, new features, or contributions.

For user guides and general information, please see:

One of the core values of the OpenWISP project is Software Reusability, for this reason openwisp-ipam provides a set of base classes which can be imported, extended and reused to create derivative apps.

In order to implement your custom version of openwisp-ipam, you need to perform the steps described in this section.

When in doubt, the code in the test project and the sample app will serve you as source of truth: just replicate and adapt that code to get a basic derivative of openwisp-ipam working.

If you want to add new users fields, please follow the tutorial to extend the openwisp-users. As an example, we have extended openwisp-users to sample_users app and added a field social_security_number in the sample_users/models.py.

Important

If you plan on using a customized version of this module, we suggest to start with it since the beginning, because migrating your data from the default module to your extended version may be time consuming.

1. Initialize your Custom Module 

The first thing you need to do is to create a new django app which will contain your custom version of openwisp-ipam.

A django app is nothing more than a python package (a directory of python scripts), in the following examples we'll call this django app myipam, but you can name it how you want:

django-admin startapp myipam

Keep in mind that the command mentioned above must be called from a directory which is available in your PYTHON_PATH so that you can then import the result into your project.

Now you need to add myipam to INSTALLED_APPS in your settings.py, ensuring also that openwisp_ipam has been removed:

INSTALLED_APPS = [
    # ... other apps ...
    "openwisp_utils.admin_theme",
    # all-auth
    "django.contrib.sites",
    "allauth",
    "allauth.account",
    "allauth.socialaccount",
    # openwisp2 modules
    "openwisp_users",
    # 'myipam',   <-- replace without your app-name here
    # admin
    "admin_auto_filters",
    "django.contrib.admin",
    # rest framework
    "rest_framework",
    # Other dependencies
    "reversion",
]

For more information about how to work with django projects and django apps, please refer to the django documentation.

2. Install `openwisp-ipam`

Install (and add to the requirements of your project) the openwisp-ipam python package:

pip install openwisp-ipam

3. Add `EXTENDED_APPS`

Add the following to your settings.py:

EXTENDED_APPS = ("openwisp_ipam",)

4. Add `openwisp_utils.staticfiles.DependencyFinder`

Add openwisp_utils.staticfiles.DependencyFinder to STATICFILES_FINDERS in your settings.py:

STATICFILES_FINDERS = [
    "django.contrib.staticfiles.finders.FileSystemFinder",
    "django.contrib.staticfiles.finders.AppDirectoriesFinder",
    "openwisp_utils.staticfiles.DependencyFinder",
]

5. Add `openwisp_utils.loaders.DependencyLoader`

Add openwisp_utils.loaders.DependencyLoader to TEMPLATES in your settings.py, but ensure it comes before django.template.loaders.app_directories.Loader:

TEMPLATES = [
    {
        "BACKEND": "django.template.backends.django.DjangoTemplates",
        "OPTIONS": {
            "loaders": [
                "django.template.loaders.filesystem.Loader",
                "openwisp_utils.loaders.DependencyLoader",
                "django.template.loaders.app_directories.Loader",
            ],
            "context_processors": [
                "django.template.context_processors.debug",
                "django.template.context_processors.request",
                "django.contrib.auth.context_processors.auth",
                "django.contrib.messages.context_processors.messages",
            ],
        },
    }
]

6. Inherit the AppConfig Class 

Please refer to the following files in the sample app of the test project:

You have to replicate and adapt that code in your project.

For more information regarding the concept of AppConfig please refer to the "Applications" section in the django documentation.

7. Create your Custom Models 

For the purpose of showing an example, we added a simple "details" field to the models of the sample app in the test project.

You can add fields in a similar way in your models.py file.

Note

If you have questions about using, extending, or developing models, refer to the "Models" section of the Django documentation.

8. Add Swapper Configurations 

Once you have created the models, add the following to your settings.py:

# Setting models for swapper module
OPENWISP_IPAM_IPADDRESS_MODEL = "myipam.IpAddress"
OPENWISP_IPAM_SUBNET_MODEL = "myipam.Subnet"

Substitute myipam with the name you chose in step 1.

9. Create Database Migrations 

Create and apply database migrations:

./manage.py makemigrations
./manage.py migrate

For more information, refer to the "Migrations" section in the django documentation.

10. Create the Admin 

Refer to the admin.py file of the sample app.

To introduce changes to the admin, you can do it in two main ways which are described below.

Note

For more information regarding how the django admin works, or how it can be customized, please refer to "The django admin site" section in the django documentation.

1. Monkey Patching 

If the changes you need to add are relatively small, you can resort to monkey patching.

For example:

from openwisp_ipam.admin import IpAddressAdmin, SubnetAdmin

SubnetAdmin.app_label = "sample_ipam"

2. Inheriting Admin Classes 

If you need to introduce significant changes and/or you don't want to resort to monkey patching, you can proceed as follows:

from django.contrib import admin
from openwisp_ipam.admin import (
    IpAddressAdmin as BaseIpAddressAdmin,
    SubnetAdmin as BaseSubnetAdmin,
)
from swapper import load_model

IpAddress = load_model("openwisp_ipam", "IpAddress")
Subnet = load_model("openwisp_ipam", "Subnet")

admin.site.unregister(IpAddress)
admin.site.unregister(Subnet)


@admin.register(IpAddress)
class IpAddressAdmin(BaseIpAddressAdmin):
    # add your changes here
    pass


@admin.register(Subnet)
class SubnetAdmin(BaseSubnetAdmin):
    app_label = "myipam"
    # add your changes here

Substitute myipam with the name you chose in step 1.

11. Create Root URL Configuration 

from .sample_ipam import views as api_views
from openwisp_ipam.urls import get_urls

urlpatterns = [
    # ... other urls in your project ...
    # openwisp-ipam urls
    # path('', include(get_urls(api_views))) <-- Use only when changing API views (dicussed below)
    path("", include("openwisp_ipam.urls")),
]

For more information about URL configuration in django, please refer to the "URL dispatcher" section in the django documentation.

12. Import the Automated Tests 

When developing a custom application based on this module, it's a good idea to import and run the base tests too, so that you can be sure the changes you're introducing are not breaking some of the existing features of openwisp-ipam.

In case you need to add breaking changes, you can overwrite the tests defined in the base classes to test your own behavior.

See the tests of the sample app to find out how to do this.

You can then run tests with:

# the --parallel flag is optional
./manage.py test --parallel myipam

Substitute myipam with the name you chose in step 1.

For more information about automated tests in django, please refer to "Testing in Django".

Other Base Classes That Can be Inherited and Extended 

The following steps are not required and are intended for more advanced customization.

1. Extending the API Views 

The API view classes can be extended into other django applications as well. Note that it is not required for extending openwisp-ipam to your app and this change is required only if you plan to make changes to the API views.

Create a view file as done in views.py.

For more information about django views, please refer to the views section in the django documentation.

Extending OpenWISP IPAM

Version