django-admin-edit-lock 0.4.0

django-admin-edit-lock is a Django application used in admin to prevent simultaneous edit by more than one users.

django-admin-edit-lock

:warning: Correct operation relies on cache. Therefore, the current version will be unreliable in cases where the default local-memory cache backend is used, along with multiple application server worker (see https://github.com/demestav/django-admin-edit-lock/issues/1).

Setup

Install package using pip:

python -m pip install django-admin-edit-lock

Add it to the installed apps:

INSTALLED_APPS = [
    ...
    "admin_edit_lock",
    ...
]

Configuration

There are two one mandatory settings:

ADMIN_EDIT_LOCK_DURATION

Defines how long each edit lock should last. The value is in seconds. For example:

ADMIN_EDIT_LOCK_DURATION = 60

will keep the lock for sixty seconds.

The lock is being updated regularly (every 5 seconds) as long as the user is still editing the object. Therefore this value needs to be larger than 5 seconds. This configuration will probably be removed in the future, as it does not really offer any value by being user-configurable. The only case this affects the user is how long the lock will remain after the user finished editing. For example, the user updated the lock at 10:00:00 (i.e. the lock expires at 10:01:00) and the user exits the edit screen (closer tab or saves or navigates back etc.) at 10:00:10. For the remaining 50 seconds, the lock will be there without any real purpose.

ADMIN_EDIT_LOCK_MAX_DURATION

Defines for how long a user can keep the same lock. The value is in seconds.

This prevents a user to keep the maintain the edit rights of an object indefinitely. This is useful in cases where a user unintentionally keeps the edit screen open and therefore not allowing other users to edit the object.

ADMIN_EDIT_LOCK_DISPLAY_OWNER

Defines whether to display the username of the user with edit rights, to other users trying to edit the same object. The value is True or False.

:warning: If this is set to True, it raises potential privacy issues.

Usage

Use the AdminEditLockMixin to enable edit lock on a model.

For example:

# models.py
from django.db import models

class Book(models.Model):
    name = models.CharField(max_length=100)

# admin.py
from django.contrib import admin
from admin_edit_lock.admin import AdminEditLockMixin


class BookAdmin(AdminEditLockMixin, admin.ModelAdmin):
    class Meta:
        model = Book

Roadmap

• Customize messages
• Extending the lock expiry time through AJAX call
• Optionally set a limit to how much the lock can be extended

Acknowledgements

This project is inspired by https://github.com/jonasundderwolf/django-admin-locking . This project differentiates by utilizing the Django permissions to decide whether a user can edit or not. Further, this project uses the messages middleware to notify the users of the lock status.