Introduction to the Fishbowl Process
Over time Zope has become a leading Open Source application server
with a large community of users and developers. In the past Digital
Creations has been a bottleneck for active participation by the
community in developing the Zope platform. One of the reasons for
this was a desire by Digital Creations to ensure a sound design
focus for the platform. As the community continues to grow it is
imperative to have an open development process that allows DC and
the community to work in concert while retaining sound software
development practices.
Digital Creations uses a mixture of key ideas of the Unified Process
championed by Rational Software, plus best practices from extreme
programming and real-world Open Source development. We are proposing
to formalize a lightweight version of these practices into the "Fishbowl
Process" that DC and the community will use to manage the development
of the Zope platform and other software projects (such as the PTK).
Fishbowl Motivations
The Fishbowl Process is the way the community, including Digital
Creations, will design and develop Zope. The name "fishbowl"
comes from the idea brought to prominence by Mozilla.org that
there are no internal conversations; rather, all communication,
decisions, arguments, and progress is visible as if everyone were
working "in a fishbowl".
These are the goals and motivations of this process:
Lightweight. The process should be as simple as possible
and should not require a great deal of learning or ceremony to
use. A process that is too heavy will eventually be ignored.
Consistency. When approaching projects, potential Zope
developers should be able to quickly come up to speed on
requirements and other project information. Likewise, people
running new projects should have a consistent body of existing
projects to emulate when running their own.
Thinking about thinking. If code is the only artifact,
we're in trouble. The requirements, design and decision-making
that lead to code are as important as the code. Equally important,
it means that non-developers can participate in the process by
commenting on (and contributing to) non-code artifacts.
Formalizing arguments. It is hard to engage a proposal
when it isn't clear what is proposed, or to debate an architecture
when you don't know what the architecture actually is. At the same
time, it is frustrating for would-be developers to be told things
such as, "You didn't write the requirements right" when there are
no examples of good requirements.
Ensuring progress. Projects that are mushy and poorly defined
are easily sidetracked and difficult to keep moving forward.
Ensuring that projects are well defined and using milestone-based
"hill-to-hill" planning as a part of the process can ensure that
projects make steady progress.
Fishbowl Structure
A project using the Fishbowl Process progresses through the same
four phases as the Unified Process: Inception, Elaboration,
Construction, and Transition. If you don't know what these mean,
that's OK. What these four phases mean in the context of the
Fishbowl Process is described below.
Inception
We have a great idea for a new capability in Zope. Where do we
start? The Inception phase is all about fleshing out our idea,
determining the scope of effort and deciding whether to proceed.
In the Fishbowl we get our great idea in play by writing a
proposal that includes:
What is the problem being solved?
What (broadly) is the proposed solution?
What are the major project risks?
What is the scope of the project?
What are the deliverables of the project?
Zope.org members can create proposals in the Proposals wiki of the
DevHome site. The Proposals wiki provides a common collaborative
environment where people can work on developing, reviewing and
providing feedback on proposals. A proposal should be a single wiki
document at this point. A proposal is "ready" for consideration as
a project when it addresses the above points and there is someone
willing to move the proposal forward as an active project.
When the proposal is ready and has a leader, the leader should
contact (zope-dev@zope.org for now) to ask that the proposal
move to the next phase and become an active project. At this
point, the maintainer of the software product in question will do
two things:
This is a recurring pattern that you'll see each time you move
into a new phase. At transition points there will be an editorial
review where we ensure that we've done things consistent with the
process and a technical review focused on the ideas of the proposal
itself.
For example, if we were to write a proposal containing only:
DTML is ugly, non-intuitive and hard. I propose to fix that.
then ask to become an active project the Zope product manager is
going to tell us that our proposal is not up to snuff from an
editorial point of view. Our proposal at this point is far too
broad and doesn't cover the points a proposal needs to address.
On the other hand maybe we have a great idea to embed video game
emulation functionality into Zope and we've created a proposal that
follows the process to the letter. In this case, the Zope product
manager will probably have technical objections to the proposal.
At the end of Inception we have:
Fleshed out our idea in a proposal that captures the problem
being solved, the proposed solution, risk factors, a statement
of the scope of the project and expected deliverables
Incorporated feedback from the community
Identified a leader for the project
Gotten editorial and technical review from the maintainer
of the relevant software product
Now we're ready to go on to the next phase: Elaboration.
Elaboration
Now that we've staked out the basic ground in our proposal, it's
time for the really hard, frustrating, but critical part. Not
writing code, but fleshing out the requirements and capturing
the major design decisions so that people can really critique
the project and understand its implications. Elaboration is all
about making sure that our project is solving the right problem
and solving the problem in the right way.
When we move into Elaboration we get a project area in DevHome.
Project areas in DevHome consist of a Folder containing a Wiki
(where most of the project work is done) and possibly a Tracker
and other tools for managing the project. Project Wikis have a
basic structure to organize the few main artifacts that are used
in a Fishbowl project. The core artifacts are the Vision Statement,
Risk List and Use Cases.
Once you have a project area, the first thing to do is put a copy
of your proposal in the Wiki for historical reference. Next you
work on the Vision Statement, which will probably be largely drawn
from the material in the proposal (though you'll often want to go
into a little more detail in the Vision Statement).
Every project implies risks, both inside the software and in
external forces. It is important for the project owner to
recognize these risks, and perhaps plan accordingly. For
instance, if the architectural choice might imply hotspots in
the Catalog that need to be worked around, the project owner
might whip up a "spike solution" (to borrow extreme programming
jargon) to prototype workarounds. The Risk List captures these
risks associated with the project and the proposed solutions
to those risks.
The broad outlines of the project captured in the Vision Statement
are then fleshed out in Use Cases. The Fishbowl Process focuses on
a pragmatic, simple approach: do as little as possible while still
achieving the main goal of truly understanding the requirements of
the project. Use Cases in the Fishbowl are not meticulously specified
with fifteen fields or so as in other processes. A Use Case in the
Fishbowl must at least:
State the goal from point of view of the user
Name the actor (kind of user) performing the use case
Provide enough descriptive text to ensure that you've thought
things through.
A good way to handle the description is to write it in a user
documentation style as if it were to be consumed by the actor.
This will often give you a head start on user documentation :^)
If you've used Use Cases in an organization before then you know
that there are endless opinions on how they should be done. The
main goal is that they provide a common understanding of the
requirements. Community review is the best way to make sure that
this goal is achieved. A good way to get started with Use Cases is
to find a project fairly similar to your own and use the way that
that project's use cases were done as a guide for your own.
As you flesh out the requirements in use cases, you will also be
able to begin defining the "architecture" for the project. The
architecture is simply a partial design that addresses the
major risks of the project. Sometimes these key design decisions
are captured in the course of architectural discussions that go on
in the project Wiki. Other times it may be better to capture them
more formally. Again, look to other projects for guidance.
Finally in Elaboration you begin planning the implementation (at
least the first few milestones). The manager of a Fishbowl project
is not expected to have an all-encompassing blow-by-blow plan to
the end of the project. The planning you do should make sure
that everyone knows what the next milestone is and what needs to
be done to hit it. This "hill-to-hill" planning keeps everyone on
the same page and ensures that the project keeps moving forward.
Once we understand the requirements, have made the key architectural
decisions and have an implementation plan it is time to have the
project manager for the software you are contributing to (Zope core,
PTK, etc.) to do editorial and technical review on the work so far.
At the end of Elaboration we have:
come to a good common understanding of the requirements
through use cases
made the key architectural decisions to deal with risks
developed a basic plan for implementing and working on
other project deliverables such as user documentation
Gotten editorial and technical review from the maintainer
of the relevant software product
If everything is in order, a CVS branch will be created for the
project team to start working on. Now we can start following our
implementation plan in the Construction phase.
Construction
The time in the fishbowl up to this point has been focused on
thinking. Now it's time to start producing some code. What's
the right way to do this?
The most imporant piece by far is to continuously plan.
Without planning, you're just a one-person show. Isn't it
important to communicate the status with people and set
expectations? Isn't it important to accept and track input?
The first Fishbowl Process approach to planning is to work on a
milestone to milestone basis. These milestones should be
frequent, and you should be specific about what is coming in the
next milestone. It is important to keep the plan up to date -
people working on the project (and especially new people who
would like to jump in and help) should always know what is
happening now and what the next milestone is.
A good way to handle this is a "status" area of the project Wiki
where people can go to quickly find out what's going on now and
what the next milestone is. For larger projects, it might be a
good idea to give the status of your project wider distribution
via the Zope Weekly News. ZWN is a facility for collecting the
status of Zope projects, packaging this up neatly, and distributing
it far and wide. The Zope.org is more than happy to do much of the
hard work of distribution if you're willing to do a good job of
giving them status reports to include.
Next, use the Tracker as a facility for accepting bug reports,
feature requests, and dumb (meaning, not your :^) ideas. You
can then schedule these issues to give people a constant idea of
where you stand and what is on your radar.
The Wiki can be your friend as well. "Water cooler" conversations
are the enemy of every project, as invariably something critical
gets communicated, and someone leaves with expectations that are
lost in the ether. Wiki pages can help collect these
unstructured tidbits.
In some cases a mailing list will be setup for substantive,
large-scale projects. Otherwise existing mailing lists can be
leveraged (for now, use zope-dev for this).
The goal of Construction is to deliver the deliverables committed
to in the Vision Statement. This often includes things beside
code - help system pages, API documentation, user manuals and
other supporting materials are often part of the deliverables.
These deliverables must be completed (and tested!) before the
project will be able to come off of the CVS branch and be merged
into the main codebase. Well-run projects should plan so that
the deliverables are worked on in parallel - you don't want to
have everyone cram to produce final code and have to wait for
API or user documentation to be done.
So at the end of Construction we have:
If everything is in order, you're ready to move on to Transition,
where the Zope community owes you a beer, where you get your
net.fame and where someone else gets to do all the hard work for
a change. :^)
Transition
Getting off your branch and onto the trunk can be a traumatic
activity. Your stuff might break some stuff, other stuff might
break your stuff. Have pity on the soul who has to sort all of
this out :^)
In transition the relevant product manager will work with you to
resolve any conflicts and make sure that all of the deliverables
go where they need to go to get into official releases.
What happens after transition? Your work goes into the next
product release and the world rejoices. More importantly, there is
a strong record of how the code came into being for people to
rely on later and another good example for future projects to
follow.
Conclusion
That's an overview of the activities for the four phases. Being a
loose approach, the Fishbowl Process relies on one thing for
success: adoption in spirit as well as form.
Created by Brian.
Last modified on 2000/07/06.
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