New Features to Add in Iteration 3

  • A visitor must authenticate (login) in order to submit a vote or change his vote(s).
  • An authenticated user gets only 1 vote per poll.
  • A user can change his vote on a poll during the voting period and his new vote replaces his old vote.
  • If a user selects a poll he already voted on, the list of choices shows which choice he/she previously selected. For example, a radio button is selected for his previous choice.
  • When a user submits a vote there is visual confirmation of his vote, such as a message on the results page “Your vote for xxxx has been saved”.
  • A visitor can login and logout.
  • A link for “Login” or “Logout” is shown on most or all web pages. In good UI design these links appear in the same place on every page (e.g. a common header or sidebar).

Other Behavior:

  • Anyone can view the list of polls and poll results (same as before)
  • (Optional) Add logging of important events, such as login, logout, failed login, and submitting a vote.

Requirements

Project Artifacts:

  • An Iteration 3 Plan in your wiki with goal, milestone(s), major work.
  • Reviewed and updated Requirements document.
  • Updated the Development Plan for iteration 3.
  • A Domain Model page in your Wiki. Include a UML class diagram and some text to explain the reasoning for your domain model.
  • Iteration 3 Task Board with complete tasks for work to do.
    • Convert task to “Issues” when it makes sense so they appear in your repo on Github.
  • iteration3 branch containing your work, merged into master.

Process Requirement:

  • Use Github Flow. Work on iteration3 branch.
  • Commit and push work regularly.
  • No credit (zero) for one big commit & push of work at end of the iteration.

Software Development:

  1. Make small changes to code and test each one so you can easily fix problems. Commit code after each successful change.
  2. Write unit tests to verify the new work is correct and satisfies requirements. A few “auth” tests are provided as starting point – please expand on them.
  3. Add at least 2 demo users to your database. In README.md add the username and password for these users. This is so we can use your application. For example 
    | Username  | Password        |
|-----------|-----------------|
|   demo1   | stupidpassword1 |
|   demo2   | stupidpassword2 |
  4. Data Fixtures Create new data files for questions, votes, and users. 
    cmd> python manage.py dumpdata --indent=2 -o data/polls.json polls 
cmd> python manage.py dumpdata --indent=2 -o data/users.json auth.user

    Note the file name is polls.json for polls data since the format will be different than old data.

(Optional) Divide Tests into Separate Files

Your code now has many unit tests. Consider separating tests into separate files, as recommended in the MDN Django Tutorial.

  • Create a polls/tests directory containing an __init__.py file.
  • Divide your tests into separate files, with related tests in one file, such as: 
    polls/tests/
           __init__.py
           test_index.py
           test_poll_dates.py
           test_auth.py
           test_voting.py
  • Delete the original tests.py file
  • Fix the imports in test files. Instead of import .models use import polls.models. Similarly for views.

(Optional) Logging

Add logging of important events:

Event Log Level
user login or logout info
unsuccessful login attempt warning
user submits a vote info
exception caught in code error
  • use Django Logging which is Python’s logging module.
  • logging methods automatically include (a) date and time, (b) location in code. This is done by the Formatter, so don’t add it in the log message you write.
  • login/logout messages should include the user’s IP address

You can configure the logger behavior, including message format, in settings.py.

An example of using logging is:

import logging

logger = logging.getLogger("polls")
logger.info(f"{user.username} logged in from {ip_addr}")
logger.warn(f"Failed login for {username} from {ip_addr}")

# Example of logging an exception.
# log.exception will include a stack trace
# log.error can be used to omit stack trace
try:
    question = Question.objects.get(id=question_id)
except Question.DoesNotExist as ex:
    logger.exception(f"Non-existent question {question_id} %s", ex)

Getting a Visitor’s IP Address for Logging

When someone logs in you should include their IP address in the log message.

There are many posts showing how to write a get_client_ip function using the Django request object. Getting the visitor’s actual IP address is harder than it looks, as commenters mention here: https://stackoverflow.com/questions/4581789/how-do-i-get-user-ip-address-in-django

One implementation uses HttpRequest headers sent by the client, HTTP_X_FORWARDED_FOR and REMOTE_ADDR

def get_client_ip(request):
    """Get the visitor’s IP address using request headers."""
    x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR')
    if x_forwarded_for:
        ip = x_forwarded_for.split(',')[0]
    else:
        ip = request.META.get('REMOTE_ADDR')
    return ip

This is OK, but request headers can be manipulated by the sender.

Resources that may help