[Python-Dev] PEP 595: Improving bugs.python.org
On Thu, May 23, 2019 at 10:17 PM Ezio Melotti <ezio.melotti at gmail.com> wrote:
> Berker and I have been working on a PEP that suggests we keep using
> and improving bugs.python.org and Roundup instead of switching to
> GitHub Issues as proposed by PEP 581.
> The PEP covers:
> * What are the advantages of Roundup over GitHub issues;
> * What features are missing in Roundup and how can we add them;
> * Issues with PEP 581;
> * Issues with the migration plan proposed by PEP 588;
> The rendered version of PEP 595 is available at
> For reference, you can consult PEP 581 and 588 at
> https://www.python.org/dev/peps/pep-0581/ and
> The full text of the PEP is include below. We are planning to update
> the PEP to include the feedback we receive and to update the status of
> features as we implement them (we also have a Google Summer of Code
> students working on it).
> Best Regards,
> Ezio Melotti
earlier today I expanded and reworded the "Migration considerations"
section and added the feedback I got from the replies.
You can find the rendered version of that section (and the rest of the
PEP) at https://www.python.org/dev/peps/pep-0595/#migration-considerations
The changeset can be found at
The full text of the latest version of the PEP is included below.
Title: Improving bugs.python.org
Author: Ezio Melotti <ezio.melotti at gmail.com>, Berker Peksag
<berker.peksag at gmail.com>
This PEP proposes a list of improvements to make bugs.python.org
more usable for contributors and core developers. This PEP also
discusses why remaining on Roundup should be preferred over
switching to GitHub Issues, as proposed by :pep:`581`.
On May 14th, 2019 :pep:`581` has been accepted [#]_ without much
public discussion and without a clear consensus [#]_. The PEP
contains factual errors and doesn't address some of the
issues that the migration to GitHub Issues might present.
Given the scope of the migration, the amount of work required,
and how it will negatively affect the workflow during the
transition phase, this decision should be re-evaluated.
Roundup advantages over GitHub Issues
This section discusses reasons why Roundup should be preferred
over GitHub Issues and Roundup features that are not available
on GitHub Issues.
* **Roundup is the status quo.** Roundup has been an integral
part of the CPython workflow for years. It is a stable product
that has been tested and customized to adapt to our needs as the
It is possible to gradually improve it and avoid the disruption
that a switch to a different system would inevitabily bring to
* **Open-source and Python powered.** Roundup is an open-source
project and is written in Python. By using it and supporting
it, we also support the Python ecosystem. Several features
developed for bpo have also been ported to upstream Roundup
over the years.
* **Fully customizable.** Roundup can be (and has been) fully
customized to fit our needs.
* **Finer-grained access control.** Roundup allows the creation
of different roles with different permissions (e.g. create,
view, edit, etc.) for each individual property, and users can
have multiple roles.
* **Flexible UI.** While Roundup UI might look dated, it is
convenient and flexible.
For example, on the issue page, each field (e.g. title, type,
versions, status, linked files and PRs, etc.) have appropriate
UI elements (input boxes, dropdowns, tables, etc.) that are
easy to set and also provide a convenient way to get info about
the issue at a glance. The number of fields, their values, and
the UI element they use is also fully customizable.
GitHub only provides labels.
The issue list page presents the issues in a compact and easy
to read table with separate columns for different fields. For
comparison, Roundup lists 50 issues in a screen, whereas GitHub
takes two screens to shows 25 issues.
* **Advanced search.** Roundup provides an accurate way to search
and filter by using any combination of issue fields.
It is also possible to customize the number of results and the
fields displayed in the table, and the sorting and grouping
(up to two levels).
bpo also provides predefined summaries (e.g. "Created by you",
"Assigned to you", etc.) and allows the creation of custom
search queries that can be conveniently accessed from the sidebar.
* **Nosy list autocomplete.** The nosy list has an autocomplete
feature that suggests maintainers and experts. The suggestions
are automatically updated when the experts index [#]_ changes.
* **Dependencies and Superseders.** Roundup allows to specify
dependencies that must be addressed before the current issues
can be closed and a superseder issue to easily mark duplicates
[#]_. The list of dependencies can also be used to create
meta-issues that references several other sub-issues [#]_.
This section lists some of the issues mentioned by :pep:`581`
and other desired features and discusses how they can be implemented
by improving Roundup and/or our instance.
* **REST API support.** A REST API will make integration with other
services and the development of new tools and applications easiers.
Upstream Roundup now supports a REST API. Updating the tracker will
make the REST API available.
* **GitHub login support.** This will allow users to login
to bugs.python.org (bpo) without having to create a new account.
It will also solve issues with confirmation emails being marked
as spam, and provide two-factor authentication.
A patch to add this functionality is already available and is
being integrated at the time of writing [#]_.
* **Markdown support and message preview and editing.** This feature
will allow the use of Markdown in messages and the ability to
preview the message before the submission and edit it afterward.
This can be done, but it will take some work. Possible solutions
have been proposed on the roundup-devel mailing list [#]_.
* **"Remove me from nosy list" button.** Add a button on issue pages
to remove self from the nosy list.
This feature will be added during GSoC 2019.
* **Mobile friendly theme.** Current theme of bugs.python.org looks
dated and it doesn't work well with mobile browsers.
A mobile-friendly theme that is more modern but still familiar
will be added.
* **Move reply box close to the last message.** The reply box is
located at the top of the page, whereas the last message is at the
The reply box can be moved or duplicated after the last message.
* **Real-time updates.** When another users submits changes to an
issue, they should show up in real time.
This can be accomplished by using the REST API.
* **Add PR link to BPO emails.** Currently bpo emails don't include
links to the corresponding PRs.
A patch [#]_ is available to change the content of the bpo emails
versions: +Python 3.4
versions: +Python 3.4
* **Python 3 support.** Using Python 3 will make maintenance easier.
Upstream Roundup now supports Python 3. Updating the tracker will
allow us to switch to Python 3. The instances will need to be
updated as well.
* **Use upstream Roundup.** We currently use a fork of Roundup with
a few modifications, most notably the GitHub integration. If this
is ported upstream, we can start using upstream Roundup without
having to maintain our fork.
PEP 581 issues
This section addresses some errors and inaccuracies found in :pep:`581`.
The "Why GitHub?" section of PEP 581 lists features currently
available on GitHub Issues but not on Roundup. Some of this features
are currently supported:
* "Ability to reply to issue and pull request conversations via email."
* Being able to reply by email has been one of the core features of
Roundup since the beginning. It is also possible to create new
issues or close existing ones, set or modify fields, and add
* "Email notifications containing metadata, integrated with Gmail,
allowing systematic filtering of emails."
* Emails sent by Roundup contains metadata that can be used for
* "Additional privacy, such as offering the user a choice to hide an
email address, while still allowing communication with the user
* Email addresses are hidden by default to users that are not
registered. Registered users can see other users' addresses
because we configured the tracker to show them. It can easily
be changed if desired. Users can still be added to the nosy
list by using their username even if their address is hidden.
* "Ability to automatically close issues when a PR has been merged."
* The GitHub integration of Roundup automatically closes issues
when a commit that contains "fixes issue <id>" is merged.
(Alternative spellings such as "closes" or "bug" are also supported.)
See [#]_ for a recent example of this feature.
* "Support for permalinks, allowing easy quoting and copying &
pasting of source code."
* Roundup has permalinks for issues, messages, attachments, etc.
In addition, Roundup allows to easily rewrite broken URLs in
messages (e.g. if the code hosting changes).
* "Core developers, volunteers, and the PSF don't have to maintain the
issue infrastructure/site, giving us more time and resources to focus
on the development of Python."
* While this is partially true, additional resources are required to
write and maintain bots.
In some cases, bots are required to workaround GitHub's lack of
features rather than expanding. [#]_ was written
specifically to workaround GitHub's email integration.
Updating our bots to stay up-to-date with changes in the GitHub API
has also maintenance cost. [#]_ took two days to be fixed.
In addition, we will still need to maintain Roundup for bpo (even
if it becomes read-only) and for the other trackers
we currently host/maintain (Jython [#]_ and Roundup [#]_).
The "Issues with Roundup / bpo" section of :pep:`581` lists some issues
that have already been fixed:
* "The upstream Roundup code is in Mercurial. Without any CI available,
it puts heavy burden on the few existing maintainers in terms of
reviewing, testing, and applying patches."
* While Roundup uses Mercurial by default, there is a git clone
available on GitHub [#]_. Roundup also has CI available [#]_ [#]_.
* "There is no REST API available. There is an open issue in Roundup for
adding REST API. Last activity was in 2016."
* The REST API has been integrated and it's now available in Roundup.
* "Users email addresses are exposed. There is no option to mask it."
* Exposing addresses to registered and logged in users was a decision
taken when our instance was set up.
This has now been changed to make the email addresses hidden for
regular users too (Developers and Coordinators can still see them).
The "Email address"" column from the user listing page [#]_ has been
* "It sends a number of unnecessary emails and notifications, and it is
difficult, if not impossible, to configure."
* This can be configured.
* "Creating an account has been a hassle. There have been reports of people
having trouble creating accounts or logging in."
* The main issue is confirmation emails being marked as spam. Work has
been done to resolve the issue.
This section describes issues with the migrations that might not
have been addressed by :pep:`581` and :pep:`588`.
:pep:`588` suggests to add a button to migrate issues to GitHub
only when someone wants to keep working on them. This approach
has several issues, but there are also other issues that will
need to be addressed regardless of the approach used:
* **Vendor lock-in.** GitHub is properietary and there is risk
of vendor lock-in. Their business model might change and they
could shut down altogether. For example, several projects
decided to move away from GitHub after Microsoft acquisition.
If/when the repository is no longer available on GitHub, we will
be forced to migrate again and all the links to the issues won't
* **Required bpo updates.** bpo will need to be updated in order
to add a button that, once pressed, creates a new issue on
GitHub, copies over all the messages, attachments, and
creates/adds labels for the existing fields. Permissions will
also need to be tweaked to make individual issues read-only
once they are migrated, and to prevent users to create new
accounts. It might be necessary to set up redirects (see below).
* **Two trackers.** If issues are migrated on demand, the issues
will be split between two trackers. Referencing and searching
issues will take significant more effort.
* **Lossy conversion.** GitHub only mechanism to add custom metadata
is through labels. bpo uses a number of fields to specify several
different metadata. Preserving all fields and values will result
in too many labels. If only some fields and values are preserved
the others will be lost (unless there is a way to preserve them
* **Issue IDs preservation.** GitHub doesn't provide a way to
set and preserve the ID of migrated issues. Some projects managed
to preserve the IDs by contacting the GitHub staff and migrating
the issues *en masse*. However, this is no longer possible, since
PRs and issues share the same namespace and PRs already use
existing bpo issue IDs.
* **Internal issue links preservation.** Existing issues might
contain references to other issues in messages and fields (e.g.
dependencies or superseder). Since the issue ID will change
during the migration, these will need to be updated. If the
issues are migrated on demand, all the existing internal
references to the migrated issues (on both bpo and GitHub issues)
will have to be updated.
Setting up a redirect for each migrated issue on bpo might
mitigate the issue, however -- if references in migrated messages
are not updated -- it will cause confusion (e.g. if bpo issue
`#1234` becomes GitHub issue `#4321`, a reference to `#1234`
in a migrated message could link to bpo `#1234` and bpo can
redirect to GitHub issue `#4321`, but new references to `#1234`
will link to GitHub PR `#1234` rather than GitHub issue `#4321`).
Manually having to specify a `bpo-` or `gh-` prefix is error prone.
* **External issue links preservation.** A number of websites,
mails, etc. link to bpo issues. If bpo is shut down, these links
will break. If we don't want to break the links, we will have to
keep bpo alive and set up a redirect system that links to the
corresponding GitHub issue.
In addition, if GitHub shuts down, we won't have any way to setup
redirects and preserve external links to GitHub issues.
* **References preservation and updating.** In addition to issue
references, bpo converts a number of other references into links,
including message and PR IDs, changeset numbers, legacy SVN
revision numbers, paths to files in the repo, files in tracebacks
(detecting the correct branch), and links to devguide pages and
Since Roundup converts references to links when messages are
requested, it is possible to update the target and generate the
correct link. This need already arised several times, for
example: files and HG changesets moved from `hg.python.org` to
GitHub and the devguide moved from `docs.python.org/devguide` to
Since messages on GitHub are static, the links will need to be
generated and hardcoded during the migration or they will be lost.
In order to update them, a tool to find all references and
regenerate the links will need to be written.
* **Roundup and bpo maintenance.** On top of the aforementioned
changes to bpo and development of tools required to migrate to
GitHub issues, we will still need to keep running and maintaining
Roundup, both for our bpo instance (read-only) and for the Jython
and Roundup trackers (read-write).
Even if eventually we migrate all bpo issues to GitHub and we stop
maintaining Jython and Roundup, bpo will need to be maintained
and redirect to the corresponding GitHub issues.
* **Bots maintenance.** Since it's not possible to customize GitHub
directly, it's also necessary to write, maintain, and host bots.
Even if eventually we stop maintaining Roundup, the maintenance
burden simply shifted from Roundup to the bots. Hosting each
different bot also has a monetary cost.
* **Using issue templates.** Manually editing issue templates to
"remove texts that don't apply to [the] issue" is cumbersome and
* **Signal to noise ratio.** Switching to GitHub Issues will
likely increase the number of invalid reports and increase
the triaging effort. This concern has been raised in the past
in a Zulip topic [#]_.
There have been already cases where people posted comments on
PRs that required moderators to mark them as off-topic or
disruptive, delete them altogether, and even lock the
* **Weekly tracker reports and stats.** Roundup sends weekly reports
to python-dev with a summary that includes new issues, recent
issues with no replies, recent issues waiting for review, most
discussed issues, closed issues, and deltas for open/closed/total
issue counts [#]_. The report provides an easy way to keep track
of the tracker activity and to make sure that issues that require
attention are noticed.
The data collect by the weekly report is also use to generate
statistics and graphs that can be used to gain new insights [#]_.
* **bpo-related MLs.** There are currently two mailing lists where
bpo posts new tracker issues and all messages respectively:
`new-bugs-announce` [#]_ and `python-bugs-list` [#]_. A new system
will need to be developed to preserve this functionality. These MLs
offer additional ways to keep track of the tracker activity.
.. [#] [Python-Dev] PEP 581 (Using GitHub issues for CPython) is accepted
.. [#] [python-committers] [Python-Dev] PEP 581 (Using GitHub issues
for CPython) is accepted
.. [#] Experts Index -- Python Devguide
.. [#] An example of superseded issues:
"re.sub() replaces only several matches"
.. [#] An example of meta issue using dependencies to track sub-issues:
"Meta-issue: support of the android platform""
.. [#] Support logging in with GitHub
.. [#] Re: [Roundup-devel] PEP 581 and Google Summer of Code
.. [#] [Tracker-discuss] [issue624] bpo emails contain useless non-github
pull_request number - users want a link to actual github PR
.. [#] The commit reported in msg342882 closes the issue (see the history below)
.. [#] The cpython-emailer-webhook project
.. [#] A recent incident caused by GitHub
.. [#] Jython issue tracker
.. [#] Roundup issue tracker
.. [#] GitHub clone of Roundup
.. [#] Travis-CI for Roundup
https://travis-ci.org/roundup-tracker/roundup) and codecov
.. [#] Codecov for Roundup
.. [#] User listing -- Python tracker
.. [#] Generating Special Links in a Comment -- Python Devguide
.. [#] The New-bugs-announce mailing list
.. [#] The Python-bugs-list mailing list
.. [#] An example of [Python-Dev] Summary of Python tracker Issues
.. [#] Issues stats -- Python tracker
.. [#] s/n ratio -- Python -- Zulip
.. [#] For example this and other related PRs:
This document has been placed in the public domain.