django-impersonate

Info:	Simple application to allow superusers to "impersonate" other non-superuser accounts.
Version:	1.3.0
Author:	Peter Sanchez (http://www.petersanchez.com)

Python / Django Support

• Python 2.7+ for Django versions 1.8 - 1.11
• Python 3.4+ for Django versions 1.9 - 2.0
• Python 3.3 for Django version 1.8

Note: In release 1.4 we plan to only support Python 3.4+ and Django 2.0+ moving forward. Bug fixes will be ported to older versions but new feature development will be focusing on modern releases of Python and Django.

Dependencies

• Depends on your project using the django.contrib.session framework.

NOTE:

• Version 1.3 adds a settings format change. Please see the Settings section for details.
• Version 1.0 adds new functionality by default. Please see the DISABLE_LOGGING settings option.
• If you need to use this with Django older than 1.8, please use version django-impersonate == 1.0.1
• If you need to use this with Django older than 1.7, please use version django-impersonate == 0.9.2
• Version 0.9.2 partially reverts work completed in version 0.9.1. This is because work done to address a request in Issue #17 broke default behavior for all previous versions. Issue #24 was opened and the fix was released in 0.9.2 to address it. Please see the new USE_HTTP_REFERER settings option.
• If you need to use this with Django older than 1.4, please use version django-impersonate == 0.5.3

Installation

PIP:

pip install django-impersonate

Basic Manual Install:

$ python setup.py build
$ sudo python setup.py install

Alternative Install (Manually):

Place impersonate directory in your Python path. Either in your Python installs site-packages directory or set your $PYTHONPATH environment variable to include a directory where the impersonate directory lives.

Use

1. Add 'impersonate' to your INSTALLED_APPS

2. Add 'impersonate.middleware.ImpersonateMiddleware' to your MIDDLEWARE_CLASSES

3. Add 'impersonate.urls' somewhere in your url structure. Example:

   urlpatterns = patterns('',
       url(r'^admin/', include(admin.site.urls)),
       url(r'^impersonate/', include('impersonate.urls')),
       ... (all your other urls here) ...
   )
   

Note: The ImpersonationMiddleware class should be placed AFTER the django.contrib.auth middleware classes

Functionality

You can now impersonate another user by hitting the following path:

/impersonate/<user-id>/

Replace <user-id> with the user id of the user you want to impersonate.

While in impersonation "mode" the request.user object will have an "is_impersonate" attribute set to True. So if you wanted to check in your templates or view, you just do something like...:

{% if user.is_impersonate %} .... {% endif %}

The original user is available as request.impersonator:

{{ request.user }} ({{ request.impersonator }})

The real user is available as request.real_user - this is equivalent to calling getattr(request, 'impersonator', request.user):

assert request.real_user == getattr(request, 'impersonator', request.user)

You can reference this URL with reverse() or the {% url %} template tag as 'impersonate-start' and expects the argument of the user ID. Example:

reverse('impersonate-start', args=[user.id])
reverse('impersonate-start', uid=user.id)

To remove the impersonation, hit the following path:

/impersonate/stop/

You can reference this URL with reverse() or the {% url %} template tag as 'impersonate-stop'. When you call this URL, you will be redirected to the page that you used to start impersonating a user (eg, some search results or the user list).

To list all users you can go to:

/impersonate/list/

This will render the template 'impersonate/list_users.html' and will pass the following in the context:

• users - queryset of all users
• paginator - Django Paginator instance
• page - Current page of objects (from Paginator)
• page_number - Current page number, defaults to 1

You can reference this URL with reverse() or the {% url %} template tag as 'impersonate-list'.

To search all users you can go to:

/impersonate/search/

This will render the template 'impersonate/search_users.html' and will pass the following in the context:

• users - queryset of all users
• paginator - Django Paginator instance
• page - Current page of objects (from Paginator)
• page_number - Current page number, defaults to 1
• query - The search query that was entered

The view will expect a GET request and look for the 'q' variable being passed. If present, it will search the user entries with the value of 'q'. The default fields searched are:

User.username, User.first_name, User.last_name, User.email

You can reference this URL with reverse() or the {% url %} template tag as 'impersonate-search'.

To allow some users to impersonate other users

You can optionally allow only some non-superuser and non-staff users to impersonate by adding a CUSTOM_ALLOW setting option. Create a function that takes a request object, and based on your rules, returns True if the user is allowed to impersonate or not.

To limit what users a user can impersonate

By, optionally, setting the CUSTOM_USER_QUERYSET option you can control what users can be impersonated. It takes a request object of the user, and returns a QuerySet of users. This is used when searching for users to impersonate, when listing what users to impersonate, and when trying to start impersonation.

Signals

If you wish to hook into the impersonation session (for instance, in order to audit access), there are two signals that are fired by django-impersonate, at the beginning and end of a session:

• session_begin - sent when calling the impersonate view
• session_end - sent when calling the stop_impersonate view

Both of these signals send the same arguments:

• sender - this is a Django signal requirement, and is always set to None
• impersonator - a reference to the User object of the person doing the impersonation
• impersonating - a reference to the User object of the person being impersonated
• request - the Django HttpRequest object from which the impersonation was invoked

The request object is included as it contains pertinent information that you may wish to audit - such as client IP address, user-agent string, etc.

For an example of how to hook up the signals, see the relevant test - test_successful_impersonation_signals.

NB The session_end signal will only be fired if the impersonator explicitly ends the session.

Settings

The following settings are available for django-impersonate. All settings should be set as variables in a dictionary assigned to the attribute named IMPERSONATE.

For example:

IMPERSONATE = {
    'REDIRECT_URL': '/some-path/',
    'PAGINATE_COUNT': 10,
}

Note: This is a new format. The old format is now deprecated and support for the old format will be removed in a future release.

Here are the options available...

REDIRECT_URL

This is the URL you want to be redirected to after you have chosen to impersonate another user. If this is not present it will check for the LOGIN_REDIRECT_URL setting and fall back to '/' if neither is present. Value should be a string containing the redirect path.

USE_HTTP_REFERER

If this is set to True, then the app will attempt to be redirect you to the URL you were at when the impersonation began once you have stopped the impersonation. For example, if you were at the url '/foo/bar/' when you began impersonating a user, once you end the impersonation, you will be redirected back to '/foo/bar/' instead of the value in REDIRECT_URL.

Value should be a boolean (True/False), defaults to False

PAGINATE_COUNT

This is the number of users to paginate by when using the list or search views. This defaults to 20. Value should be an integer.

REQUIRE_SUPERUSER

If this is set to True, then only users who have 'is_superuser' set to True will be allowed to impersonate other users. Default is False. If False, then any 'is_staff' user will be able to impersonate other users.

Note: Regardless of this setting, a 'is_staff' user will not be allowed to impersonate a 'is_superuser' user.

Value should be a boolean (True/False)

If the CUSTOM_ALLOW is set, then that custom function is used, and this setting is ignored.

ALLOW_SUPERUSER

By default, superusers cannot be impersonated; this setting allows for that.

Note: Even when this is true, only superusers can impersonate other superusers, regardless of the value of REQUIRE_SUPERUSER.

Value should be a boolean (True/False), and the default is False.

URI_EXCLUSIONS

Set to a list/tuple of url patterns that, if matched, user impersonation is not completed. It defaults to:

(r'^admin/',)

If you do not want to use even the default exclusions then set the setting to an emply list/tuple.

CUSTOM_USER_QUERYSET

A string that represents a function (e.g. 'module.submodule.mod.function_name') that allows more fine grained control over what users a user can impersonate. It takes one argument, the request object, and should return a QuerySet. Only the users in this queryset can be impersonated.

This function will not be called when the request has an unauthorised users, and will only be called when the user is allowed to impersonate (cf. REQUIRE_SUPERUSER and CUSTOM_ALLOW ).

Regardless of what this function returns, a user cannot impersonate a superuser, even if there are superusers in the returned QuerySet.

It is optional, and if it is not present, the user can impersonate any user (i.e. the default is User.objects.all()).

CUSTOM_ALLOW

A string that represents a function (e.g. 'module.submodule.mod.function_name') that allows more fine grained control over who can use the impersonation. It takes one argument, the request object, and should return True to allow impesonation. Regardless of this setting, the user must be logged in to impersonate. If this setting is used, REQUIRE_SUPERUSER is ignored.

It is optional, and if it is not present, the previous rules about superuser and REQUIRE_SUPERUSER apply.

REDIRECT_FIELD_NAME

A string that represents the name of a request (GET) parameter which contains the URL to redirect to after impersonating a user. This can be used to redirect to a custom page after impersonating a user. Example:

# in settings.py
IMPERSONATE = {'REDIRECT_FIELD_NAME': 'next'}

# in your view
<a href="{% url 'impersonate-list' %}?next=/some/url/">switch user</a>

To return always to the current page after impersonating a user, use request.path:

<a href="{% url 'impersonate-list' %}?next={{request.path}}">switch user</a>

SEARCH_FIELDS

Array of user model fields used for building searching query. Default value is [User.USERNAME_FIELD, 'first_name', 'last_name', 'email']. If the User model doesn't have the USERNAME_FIELD attribute, it falls back to 'username' (< Django 1.5).

LOOKUP_TYPE

A string that represents SQL lookup type for searching users by query on fields above. It is 'icontains' by default.

DISABLE_LOGGING

A bool that can be used to disable the logging of impersonation sessions. By default each impersonation session_begin signal will create a new ImpersonationLog object, which is closed out (duration calculated) at the corresponding session_end signal.

It is optional, and defaults to False (i.e. logging is enabled).

MAX_FILTER_SIZE

The max number of items acceptable in the admin list filters. If the number of items exceeds this, then the filter is removed (just shows all). This is used by the "Filter by impersonator" filter.

It is optional, and defaults to 100.

SETTINGS PRIOR TO VERSION 1.3

Prior to version 1.3, settings were not stored in a dictionary. They were each an individual setting. For the time being, you can still use individual settings for each option. If present, they will supersede any setting within the IMPERSONATE dictionary and will also issue a warning that the settings format has changed and you should convert your projects settings to use the new dictionary format.

All dictionary options can be used as individual settings by simply prepending IMPERSONATE_ to the name. For example, the following is the dictionary sample from above and it's old style settings equivalent.

New format:

IMPERSONATE = {
    'REDIRECT_URL': '/some-path/',
    'PAGINATE_COUNT': 10,
}

Deprecated (old) format:

IMPERSONATE_REDIRECT_URL = '/some-path'
IMPERSONATE_PAGE_COUNT = 10

Admin

As of version 1.3 django-impersonate now includes a helper admin mixin, located at imepersonate.admin.UserAdminImpersonateMixin, to include in your User model's ModelAdmin. This provides a direct link to impersonate users from your user model's Django admin list view. Using it is very simple, however if you're using the default django.contrib.auth.models.User model you will need to unregister the old ModelAdmin before registering your own.

The UserAdminImpersonateMixin has a attribute named open_new_window that defaults to False. If this is set to True a new window will be opened to start the new impersonation session when clicking the impersonate link directly in the admin.

Here's an example:

# yourapp/admin.py
from django.contrib import admin
from django.contrib.auth.models import User
from django.contrib.auth.admin import UserAdmin
from impersonate.admin import UserAdminImpersonateMixin


class NewUserAdmin(UserAdminImpersonateMixin, UserAdmin):
    open_new_window = True
    pass

admin.site.unregister(User)
admin.site.register(User, NewUserAdmin)

Testing

You need factory_boy installed for tests to run. To install, use:

$ pip install factory_boy

Note: This is currently not required for Python 3.3+. For more info on factory_boy, see: https://github.com/dnerdy/factory_boy

From the repo checkout, ensure you have Django in your PYTHONPATH and run:

$ python runtests.py

To get test coverage, use:

$ coverage run --branch runtests.py
$ coverage html  <- Pretty HTML files for you
$ coverage report -m  <- Ascii report

If you're bored and want to test all the supported environments, you'll need tox.:

$ pip install tox
$ tox

And you should see:

py3.6-django2.0: commands succeeded
py3.6-django1.11: commands succeeded
py3.5-django1.11: commands succeeded
py3.5-django1.10: commands succeeded
py3.5-django1.9: commands succeeded
py3.5-django1.8: commands succeeded
py3.4-django1.11: commands succeeded
py3.4-django1.10: commands succeeded
py3.4-django1.9: commands succeeded
py3.4-django1.8: commands succeeded
py3.3-django1.8: commands succeeded
py2.7-django1.11: commands succeeded
py2.7-django1.10: commands succeeded
py2.7-django1.9: commands succeeded
py2.7-django1.8: commands succeeded
congratulations :)

Copyright & Warranty

All documentation, libraries, and sample code are Copyright 2011 Peter Sanchez <petersanchez@gmail.com>. The library and sample code are made available to you under the terms of the BSD license which is contained in the included file, BSD-LICENSE.

Commercial Support

This software, and lots of other software like it, has been built in support of many of Netlandish's own projects, and the projects of our clients. We would love to help you on your next project so get in touch by dropping us a note at hello@netlandish.com.