GLEP:1
Title:GLEP Purpose and Guidelines
Version:1.12
Last-Modified:2008/06/05 06:05:32
Author:Grant Goodyear <g2boojum at gentoo.org>
Status:Active
Type:Informational
Content-Type:text/x-rst
Created:31-May-2003
Post-History:1-Jun-2003, 2-Jul-2003, 19-Jan-2008, 05-Jun-2008, 09-Mar-2011

Contents

Credits

The GLEP concept, and, in fact, much of the text of this document, is liberally stolen from Python's [1] PEPs [2], especially PEP-0001 [3] by Barry A. Warsaw, Jeremy Hylton, and David Goodger.

What is a GLEP?

GLEP stands for "Gentoo Linux Enhancement Proposal". A GLEP is a design document providing information to the Gentoo Linux community, or describing a new feature for Gentoo Linux. The GLEP should provide a concise technical specification of the feature and rationale for the feature.

We intend GLEPs to be the primary mechanisms for proposing significant new features, for collecting community input on an issue, and for documenting the design decisions that have gone into Gentoo Linux. The GLEP author is responsible for building consensus within the community and documenting dissenting opinions.

Because the GLEPs are maintained as text files under CVS control, their revision history is the historical record of the feature proposal [4].

Kinds of GLEPs

There are two kinds of GLEPs. A Standards Track GLEP describes a new feature or implementation for Gentoo Linux. An Informational GLEP describes provides general guidelines or information to the Gentoo Linux community, but does not propose a new feature. Informational GLEPs do not necessarily represent a Gentoo Linux community consensus or recommendation, so users and implementors are free to ignore Informational GLEPs or follow their advice.

GLEP Work Flow

The GLEP editors assign GLEP numbers and change their status. The current GLEP editors are Grant Goodyear and Alastair Tse. Please send all GLEP-related email to <glep@gentoo.org>.

The GLEP process begins with a new idea for Gentoo Linux. It is highly recommended that a single GLEP contain a single key proposal or new idea. The more focussed the GLEP, the more successful it tends to be. The GLEP editors reserve the right to reject GLEP proposals if they appear too unfocussed or too broad. If in doubt, split your GLEP into several well-focussed ones.

Each GLEP must have a champion -- someone who writes the GLEP using the style and format described below, shepherds the discussions in the appropriate forums, and attempts to build community consensus around the idea. The GLEP champion (a.k.a. Author) should first attempt to ascertain whether the idea is GLEP-able. Small enhancements or patches often don't need a GLEP and can be injected into the Gentoo Linux development work flow with an enhancement "bug" submitted to the Gentoo Linux bugzilla [6].

The GLEP champion then emails the GLEP editors <glep@gentoo.org> with a proposed title and a rough, but fleshed out, draft of the GLEP. This draft must be written in GLEP style as described below.

If the GLEP editor accepts the GLEP, he will assign the GLEP a number, label it as Standards Track (a better name would be nice here -- suggestions?) or Informational, give it status "Draft", and create and check-in the initial draft of the GLEP. The GLEP editors will not unreasonably deny a GLEP. Reasons for denying GLEP status include duplication of effort, being technically unsound, not providing proper motivation or addressing backwards compatibility, or not in keeping with Gentoo Linux philosophy.

If a pre-GLEP is rejected, the author may elect to take the pre-GLEP to the gentoo-dev@gentoo.org mailing list to help flesh it out, gain feedback and consensus from the community at large, and improve the GLEP for re-submission.

The author of the GLEP is then responsible for posting the GLEP to the gentoo-dev mailing list (and additionally to the Gentoo Linux forums [7] if they so desire), and marshaling community support for it. As updates are necessary, the GLEP author may check in new versions directly, or forward to a Gentoo developer with commit access.

Standards Track GLEPs consist of two parts, a design document and a reference implementation. The GLEP should be reviewed and accepted before a reference implementation is begun, unless a reference implementation will aid people in studying the GLEP. Standards Track GLEPs must include an implementation -- in the form of code, patch, or URL to same -- before it can be considered Final.

GLEP authors are responsible for collecting community feedback on a GLEP before submitting it for review. A GLEP that has not been discussed on gentoo-dev@gentoo.org and the Gentoo Linux forums [7] will not be accepted. However, wherever possible, long open-ended discussions on public mailing lists should be avoided. Strategies to keep the discussions efficient include setting up a specific forums thread for the topic, having the GLEP author accept private comments in the early design phases, etc. GLEP authors should use their discretion here.

Once the authors have completed a GLEP, they must inform the Gentoo Council [8] that it is ready for review by way of the gentoo-dev mailing list. GLEPs are then reviewed at a Council meeting where the may be approved or rejected outright, or sent back to the author(s) for revision. This generally should be done a few weeks in advance of the actual review so as to avoid the appearance of "slipping" a GLEP in without proper public review by the Gentoo developer community.

For a GLEP to be approved it must meet certain minimum criteria. It must be a clear and complete description of the proposed enhancement. The enhancement must represent a net improvement. The proposed implementation, if applicable, must be solid and must not complicate the distribution unduly. Finally, a proposed enhancement must satisfy the philosophy of Gentoo Linux.

Once a GLEP has been accepted, the reference implementation must be completed. When the reference implementation is complete and accepted, the status will be changed to "Final".

A GLEP can also be assigned status "Deferred". The GLEP author or editor can assign the GLEP this status when no progress is being made on the GLEP. Once a GLEP is deferred, the GLEP editor can re-assign it to draft status.

A GLEP can also be "Rejected". Perhaps after all is said and done it was not a good idea. It is still important to have a record of this fact.

GLEPs can also be replaced by a different GLEP, rendering the original obsolete (where version 2 of a policy, for example, might replace version 1).

GLEP work flow is as follows:

Draft -> Accepted -> Final -> Replaced
  ^
  +----> Rejected
  v
Deferred

Some Informational GLEPs may also have a status of "Active" if they are never meant to be completed. E.g. GLEP 1 (this GLEP).

What belongs in a successful GLEP?

Each GLEP should have the following parts:

  1. Preamble -- RFC 822 style headers containing meta-data about the GLEP, including the GLEP number, a short descriptive title (limited to a maximum of 44 characters), the names, and optionally the contact info for each author, etc.

  2. Abstract -- a short (~200 word) description of the technical issue being addressed.

  3. Motivation -- The motivation is critical for GLEPs that want to modify Gentoo Linux functionality. It should clearly explain why the existing functionality or policy is inadequate to address the problem that the GLEP solves. GLEP submissions without sufficient motivation may be rejected outright.

  4. Specification -- The technical specification should describe the specific areas of Gentoo Linux that would be touched by this GLEP. If new functionality is being introduced, what packages will that functionality affect? If new policy, who will be affected?

  5. Rationale -- The rationale fleshes out the specification by describing what motivated the design and why particular design decisions were made. It should describe alternate designs that were considered and related work, e.g. how the feature is supported in other distributions.

    The rationale should provide evidence of consensus within the community and discuss important objections or concerns raised during discussion.

  6. Backwards Compatibility -- All GLEPs must include a section describing any issues of backwards incompatibilities and their severity. The GLEP must explain how the author proposes to deal with these incompatibilities. (Even if there are none, this section should be included to clearly state that fact.) GLEP submissions without a sufficient backwards compatibility treatise may be rejected outright.

  7. Reference Implementation -- The reference implementation must be completed before any GLEP is given status "Final", but it need not be completed before the GLEP is accepted. It is better to finish the specification and rationale first and reach consensus on it before writing code or significantly modifying ebuilds.

  8. Copyright/public domain -- Each GLEP must either be explicitly labelled as placed in the public domain (see this GLEP as an example) or licensed under the Open Publication License [#OPL].

GLEP Formating and Template

GLEPs are written either in Gentoo Linux Guide-XML [11] or in a just-barely-marked-up version of plain ASCII text called ReStructuredText [10] that is then converted to HTML using Docutils [12]. Using ReStructuredText GLEPs allows for rich markup that is still quite easy to read, but results in much better-looking and more functional HTML. Moreover, it should be straightforward to convert GLEPs to Gentoo Linux guide xml [11] if needed. GLEP 2 contains a boilerplate template [5] for use with ReStructuredText GLEPs.

GLEP Header Preamble

Each GLEP must begin with an RFC 2822 style header preamble. The headers must appear in the following order. Headers marked with "*" are optional and are described below. All other headers are required.

  GLEP: <glep number>
  Title: <glep title>
  Version: <cvs version string>
  Last-Modified: <cvs date string>
  Author: <list of authors' real names and optionally, email addrs>
* Discussions-To: <email address>
  Status: <Draft | Active | Accepted | Deferred | Rejected |
           Final | Replaced>
  Type: <Informational | Standards Track>
* Content-Type: <text/plain | text/x-rst>
* Requires: <glep numbers>
  Created: <date created on, in dd-mmm-yyyy format>
  Post-History: <dates of postings to gentoo-dev>
* Replaces: <glep number>
* Replaced-By: <glep number>

The Author header lists the names, and optionally the email addresses of all the authors/owners of the GLEP. The format of the Author header value must be

Random J. User <address@dom.ain>

if the email address is included, and just

Random J. User

if the address is not given.

If there are multiple authors, each should be on a separate line following RFC 2822 continuation line conventions. Note that personal email addresses in GLEPs will be obscured as a defense against spam harvesters.

While a GLEP is in private discussions (usually during the initial Draft phase), a Discussions-To header will indicate the mailing list or URL where the GLEP is being discussed. No Discussions-To header is necessary if the GLEP is being discussed privately with the author, or on the gentoo-dev mailing list. Note that email addresses in the Discussions-To header will not be obscured.

The Type header specifies the type of GLEP: Informational or Standards Track.

The format of a GLEP is specified with a Content-Type header, which should read "text/xml" for Gentoo Guide XML or "text/x-rst" for ReStructuredText GLEPs (see GLEP 2 [5]).

The Created header records the date that the GLEP was assigned a number, while Post-History is used to record the dates of when new versions of the GLEP are posted to gentoo-dev. Both headers should be in dd-mmm-yyyy format, e.g. 14-Aug-2001.

GLEPs may have a Requires header, indicating the GLEP numbers that this GLEP depends on.

GLEPs may also have a Replaced-By header indicating that a GLEP has been rendered obsolete by a later document; the value is the number of the GLEP that replaces the current document. The newer GLEP must have a Replaces header containing the number of the GLEP that it rendered obsolete.

Reporting GLEP Bugs, or Submitting GLEP Updates

How you report a bug, or submit a GLEP update depends on several factors, such as the maturity of the GLEP, the preferences of the GLEP author, and the nature of your comments. For the early draft stages of the GLEP, it's probably best to send your comments and changes directly to the GLEP author. For more mature, or finished GLEPs you may want to submit corrections to the Gentoo Linux bugzilla [6] so that your changes don't get lost. If the GLEP author is a Gentoo Linux developer, assign the bug/patch to him, otherwise assign it to the GLEP editors.

When in doubt about where to send your changes, please check first with the GLEP author and/or GLEP editors.

GLEP authors who are also Gentoo Linux developers can update the GLEPs themselves by using "cvs commit" to commit their changes.

Transferring GLEP Ownership

It occasionally becomes necessary to transfer ownership of GLEPs to a new champion. In general, we'd like to retain the original author as a co-author of the transferred GLEP, but that's really up to the original author. A good reason to transfer ownership is because the original author no longer has the time or interest in updating it or following through with the GLEP process, or has fallen off the face of the 'net (i.e. is unreachable or not responding to email). A bad reason to transfer ownership is because you don't agree with the direction of the GLEP. We try to build consensus around a GLEP, but if that's not possible, you can always submit a competing GLEP.

If you are interested in assuming ownership of a GLEP, send a message asking to take over, addressed to both the original author and the GLEP editors <glep@gentoo.org>. If the original author doesn't respond to email in a timely manner, the GLEP editors will make a unilateral decision (it's not like such decisions can't be reversed :).

References and Footnotes

[1]http://www.python.org
[2]http://www.python.org/peps
[3]http://www.python.org/peps/pep-0001.html
[4]This historical record is available by the normal CVS commands for retrieving older revisions. For those without direct access to the CVS tree, you can browse the current and past GLEP revisions via the Gentoo Linux viewcvs web site at http://www.gentoo.org/cgi-bin/viewcvs.cgi/gentoo/xml/htdocs/proj/en/glep/
[5](1, 2) GLEP 2, Sample ReStructuredText GLEP Template, (http://glep.gentoo.org/glep-0002.html)
[6](1, 2) http://bugs.gentoo.org
[7](1, 2) http://forums.gentoo.org
[8]http://www.gentoo.org/proj/en/glep/glep-0039.html
[9]http://www.opencontent.org/openpub/
[10]http://docutils.sourceforge.net/rst.html
[11](1, 2) http://www.gentoo.org/doc/en/xml-guide.xml
[12]http://docutils.sourceforge.net/