django/docs/internals/contributing/triaging-tickets.txt

================
Triaging tickets
================

Django uses Trac_ for managing the work on the code base. Trac is a
community-tended garden of the bugs people have found and the features people
would like to see added. As in any garden, sometimes there are weeds to be
pulled and sometimes there are flowers and vegetables that need picking. We need
your help to sort out one from the other, and in the end we all benefit
together.

Like all gardens, we can aspire to perfection but in reality there's no such
thing. Even in the most pristine garden there are still snails and insects.
In a community garden there are also helpful people who -- with the best of
intentions -- fertilize the weeds and poison the roses. It's the job of the
community as a whole to self-manage, keep the problems to a minimum, and
educate those coming into the community so that they can become valuable
contributing members.

Similarly, while we aim for Trac to be a perfect representation of the state of
Django's progress, we acknowledge that this will not happen. By distributing
the load of Trac maintenance to the community, we accept that there will be
mistakes. Trac is "mostly accurate", and we give allowances for the fact that
sometimes it will be wrong. That's okay. We're perfectionists with deadlines.

We rely on the community to keep participating, keep tickets as accurate as
possible, and raise issues for discussion on our mailing lists when there is
confusion or disagreement.

Django is a community project, and every contribution helps. We can't do this
without **you**!

Triage workflow
===============

Unfortunately, not all bug reports and feature requests in the ticket tracker
provide all the :doc:`required details<bugs-and-features>`. A number of
tickets have patches, but those patches don't meet all the requirements of a
:ref:`good patch<patch-style>`.

One way to help out is to *triage* tickets that have been created by other
users.

Most of the workflow is based around the concept of a ticket's
:ref:`triage stages <triage-stages>`. Each stage describes where in its
lifetime a given ticket is at any time. Along with a handful of flags, this
attribute easily tells us what and who each ticket is waiting on.

Since a picture is worth a thousand words, let's start there:

.. image:: /internals/_images/triage_process.*
   :height: 501
   :width: 400
   :alt: Django's ticket triage workflow

We've got two roles in this diagram:

* Committers: people with commit access who are responsible for making the
  final decision to merge a patch.

* Ticket triagers: anyone in the Django community who chooses to
  become involved in Django's development process. Our Trac installation
  is intentionally left open to the public, and anyone can triage tickets.
  Django is a community project, and we encourage :ref:`triage by the
  community<how-can-i-help-with-triaging>`.

By way of example, here we see the lifecycle of an average ticket:

* Alice creates a ticket and sends an incomplete pull request (no tests,
  incorrect implementation).

* Bob reviews the pull request, marks the ticket as "Accepted", "needs tests",
  and "patch needs improvement", and leaves a comment telling Alice how the
  patch could be improved.

* Alice updates the pull request, adding tests (but not changing the
  implementation). She removes the two flags.

* Charlie reviews the pull request and resets the "patch needs improvement"
  flag with another comment about improving the implementation.

* Alice updates the pull request, fixing the implementation. She removes the
  "patch needs improvement" flag.

* Daisy reviews the pull request and marks the ticket as "Ready for checkin".

* Jacob, a committer, reviews the pull request and merges it.

Some tickets require much less feedback than this, but then again some tickets
require much much more.

.. _triage-stages:

Triage stages
=============

Below we describe in more detail the various stages that a ticket may flow
through during its lifetime.

Unreviewed
----------

The ticket has not been reviewed by anyone who felt qualified to make a
judgment about whether the ticket contained a valid issue, a viable feature,
or ought to be closed for any of the various reasons.

Accepted
--------

The big gray area! The absolute meaning of "accepted" is that the issue
described in the ticket is valid and is in some stage of being worked on.
Beyond that there are several considerations:

* **Accepted + No Flags**

  The ticket is valid, but no one has submitted a patch for it yet. Often this
  means you could safely start writing a patch for it. This is generally more
  true for the case of accepted bugs than accepted features. A ticket for a bug
  that has been accepted means that the issue has been verified by at least one
  triager as a legitimate bug - and should probably be fixed if possible. An
  accepted new feature may only mean that one triager thought the feature would
  be good to have, but this alone does not represent a consensus view or imply
  with any certainty that a patch will be accepted for that feature. Seek more
  feedback before writing an extensive patch if you are in doubt.

* **Accepted + Has Patch**

  The ticket is waiting for people to review the supplied patch. This means
  downloading the patch and trying it out, verifying that it contains tests
  and docs, running the test suite with the included patch, and leaving
  feedback on the ticket.

* **Accepted + Has Patch + Needs ...**

  This means the ticket has been reviewed, and has been found to need further
  work. "Needs tests" and "Needs documentation" are self-explanatory. "Patch
  needs improvement" will generally be accompanied by a comment on the ticket
  explaining what is needed to improve the code.

Ready For Checkin
-----------------

The ticket was reviewed by any member of the community other than the person
who supplied the patch and found to meet all the requirements for a
commit-ready patch. A committer now needs to give the patch a final
review prior to being committed. See the
:ref:`New contributors' FAQ<new-contributors-faq>` for "My ticket has been in
RFC forever! What should I do?"

Someday/Maybe
-------------

This stage isn't shown on the diagram. It's used sparingly to keep track of
high-level ideas or long term feature requests.

These tickets are uncommon and overall less useful since they don't describe
concrete actionable issues. They are enhancement requests that we might
consider adding someday to the framework if an excellent patch is submitted.
They are not a high priority.

Other triage attributes
=======================

A number of flags, appearing as checkboxes in Trac, can be set on a ticket:

Has patch
---------

This means the ticket has an associated
:doc:`patch<writing-code/submitting-patches>`. These will be reviewed
to see if the patch is "good".

The following three fields (Needs documentation, Needs tests,
Patch needs improvement) apply only if a patch has been supplied.

Needs documentation
-------------------

This flag is used for tickets with patches that need associated
documentation. Complete documentation of features is a prerequisite
before we can check them into the codebase.

Needs tests
-----------

This flags the patch as needing associated unit tests. Again, this
is a required part of a valid patch.

Patch needs improvement
-----------------------

This flag means that although the ticket *has* a patch, it's not quite
ready for checkin. This could mean the patch no longer applies
cleanly, there is a flaw in the implementation, or that the code
doesn't meet our standards.

Easy pickings
-------------

Tickets that would require small, easy, patches.

Type
----

Tickets should be categorized by *type* between:

* New Feature
    For adding something new.

* Bug
    For when an existing thing is broken or not behaving as expected.

* Cleanup/optimization
    For when nothing is broken but something could be made cleaner,
    better, faster, stronger.

Component
---------

Tickets should be classified into *components* indicating which area of
the Django codebase they belong to. This makes tickets better organized and
easier to find.

Severity
--------

The *severity* attribute is used to identify blockers, that is, issues which
should get fixed before releasing the next version of Django. Typically those
issues are bugs causing regressions from earlier versions or potentially
causing severe data losses. This attribute is quite rarely used and the vast
majority of tickets have a severity of "Normal".

Version
-------

It is possible to use the *version* attribute to indicate in which
version the reported bug was identified.

UI/UX
-----

This flag is used for tickets that relate to User Interface and User
Experiences questions. For example, this flag would be appropriate for
user-facing features in forms or the admin interface.

Cc
--

You may add your username or email address to this field to be notified when
new contributions are made to the ticket.

Keywords
--------

With this field you may label a ticket with multiple keywords. This can be
useful, for example, to group several tickets of a same theme. Keywords can
either be comma or space separated. Keyword search finds the keyword string
anywhere in the keywords. For example, clicking on a ticket with the keyword
"form" will yield similar tickets tagged with keywords containing strings such
as "formset", "modelformset", and "ManagementForm".

.. _closing-tickets:

Closing Tickets
===============

When a ticket has completed its useful lifecycle, it's time for it to be
closed. Closing a ticket is a big responsibility, though. You have to be sure
that the issue is really resolved, and you need to keep in mind that the
reporter of the ticket may not be happy to have their ticket closed (unless
it's fixed, of course). If you're not certain about closing a ticket, leave a
comment with your thoughts instead.

If you do close a ticket, you should always make sure of the following:

* Be certain that the issue is resolved.

* Leave a comment explaining the decision to close the ticket.

* If there is a way they can improve the ticket to reopen it, let them know.

* If the ticket is a duplicate, reference the original ticket. Also
  cross-reference the closed ticket by leaving a comment in the original one
  -- this allows to access more related information about the reported bug
  or requested feature.

* **Be polite.** No one likes having their ticket closed. It can be
  frustrating or even discouraging. The best way to avoid turning people
  off from contributing to Django is to be polite and friendly and to offer
  suggestions for how they could improve this ticket and other tickets in
  the future.

A ticket can be resolved in a number of ways:

* fixed
      Used once a patch has been rolled into Django and the issue is fixed.

* invalid
      Used if the ticket is found to be incorrect. This means that the
      issue in the ticket is actually the result of a user error, or
      describes a problem with something other than Django, or isn't
      a bug report or feature request at all (for example, some new users
      submit support queries as tickets).

* wontfix
      Used when a someone decides that the request isn't appropriate for
      consideration in Django. Sometimes a ticket is closed as "wontfix" with a
      request for the reporter to start a discussion on the |django-developers|
      mailing list if they feel differently from the rationale provided by the
      person who closed the ticket. Other times, a mailing list discussion
      precedes the decision to close a ticket. Always use the mailing list to
      get a consensus before reopening tickets closed as "wontfix".

* duplicate
      Used when another ticket covers the same issue. By closing duplicate
      tickets, we keep all the discussion in one place, which helps
      everyone.

* worksforme
      Used when the ticket doesn't contain enough detail to replicate
      the original bug.

* needsinfo
      Used when the ticket does not contain enough information to replicate
      the reported issue but is potentially still valid. The ticket
      should be reopened when more information is supplied.

If you believe that the ticket was closed in error -- because you're
still having the issue, or it's popped up somewhere else, or the triagers have
made a mistake -- please reopen the ticket and provide further information.
Again, please do not reopen tickets that have been marked as "wontfix" and
bring the issue to |django-developers| instead.

.. _how-can-i-help-with-triaging:

How can I help with triaging?
=============================

The triage process is primarily driven by community members. Really,
**ANYONE** can help.

To get involved, start by `creating an account on Trac`_. If you have an
account but have forgotten your password, you can reset it using the `password
reset page`_.

Then, you can help out by:

* Closing "Unreviewed" tickets as "invalid", "worksforme", or "duplicate", or
  "wontfix".

* Closing "Unreviewed" tickets as "needsinfo" when the description is too
  sparse to be actionable, or when they're feature requests requiring a
  discussion on |django-developers|.

* Correcting the "Needs tests", "Needs documentation", or "Has patch"
  flags for tickets where they are incorrectly set.

* Setting the "`Easy pickings`_" flag for tickets that are small and
  relatively straightforward.

* Set the *type* of tickets that are still uncategorized.

* Checking that old tickets are still valid. If a ticket hasn't seen
  any activity in a long time, it's possible that the problem has been
  fixed but the ticket hasn't yet been closed.

* Identifying trends and themes in the tickets. If there are a lot of bug
  reports about a particular part of Django, it may indicate we should
  consider refactoring that part of the code. If a trend is emerging,
  you should raise it for discussion (referencing the relevant tickets)
  on |django-developers|.

* Verify if patches submitted by other users are correct. If they are correct
  and also contain appropriate documentation and tests then move them to the
  "Ready for Checkin" stage. If they are not correct then leave a comment to
  explain why and set the corresponding flags ("Patch needs improvement",
  "Needs tests" etc.).

.. note::

    The `Reports page`_ contains links to many useful Trac queries, including
    several that are useful for triaging tickets and reviewing patches as
    suggested above.

    You can also find more :doc:`new-contributors`.

    .. _Reports page: https://code.djangoproject.com/wiki/Reports

However, we do ask the following of all general community members working in
the ticket database:

* Please **don't** promote your own tickets to "Ready for checkin". You
  may mark other people's tickets which you've reviewed as "Ready for
  checkin", but you should get at minimum one other community member to
  review a patch that you submit.

* Please **don't** reverse a decision without posting a message to
  |django-developers| to find consensus.

* If you're unsure if you should be making a change, don't make the
  change but instead leave a comment with your concerns on the ticket,
  or post a message to |django-developers|. It's okay to be unsure,
  but your input is still valuable.

.. _Trac: https://code.djangoproject.com/
.. _`easy pickings`: https://code.djangoproject.com/query?status=!closed&easy=1
.. _`creating an account on Trac`: https://www.djangoproject.com/accounts/register/
.. _password reset page: https://www.djangoproject.com/accounts/password/reset/

Bisecting a regression
======================

.. highlight:: console

A regression is a bug that's present in some newer version of Django but not in
an older one. An extremely helpful piece of information is the commit that
introduced the regression. Knowing the commit that caused the change in
behavior helps identify if the change was intentional or if it was an
inadvertent side-effect. Here's how you can determine this.

Begin by writing a regression test for Django's test suite for the issue. For
example, we'll pretend we're debugging a regression in migrations. After you've
written the test and confirmed that it fails on the latest master, put it in a
separate file that you can run standalone. For our example, we'll pretend we
created ``tests/migrations/test_regression.py``, which can be run with::

    $ ./runtests.py migrations.test_regression

Next, we mark the current point in history as being "bad" since the test fails::

    $ git bisect bad
    You need to start by "git bisect start"
    Do you want me to do it for you [Y/n]? y

Now, we need to find a point in git history before the regression was
introduced (i.e. a point where the test passes). Use something like
``git checkout HEAD~100`` to checkout an earlier revision (100 commits earlier,
in this case). Check if the test fails. If so, mark that point as "bad"
(``git bisect bad``), then checkout an earlier revision and recheck. Once you
find a revision where your test passes, mark it as "good"::

    $ git bisect good
    Bisecting: X revisions left to test after this (roughly Y steps)
    ...

Now we're ready for the fun part: using ``git bisect run`` to automate the rest
of the process::

    $ git bisect run tests/runtests.py migrations.test_regression

You should see ``git bisect`` use a binary search to automatically checkout
revisions between the good and bad commits until it finds the first "bad"
commit where the test fails.

Now, report your results on the Trac ticket, and please include the regression
test as an attachment. When someone writes a fix for the bug, they'll already
have your test as a starting point.