Note: This is an outdated document. It’s more or less the historical
reasons for a lot of things. That doesn’t mean these decisions have
stayed the same or we haven’t changed our minds on some things!
Chris came up with the name MediaGoblin. The name is pretty fun.
It merges the idea that this is a Media hosting project with
Goblin which sort of sounds like gobbling. Here’s a piece of
software that gobbles up your media for all to see.
a legendary evil or mischievous illiterate creature, described
as grotesquely evil or evil-like phantom
So are we evil? No. Are we mischievous or illiterate? Not
really. So what kind of goblin are we thinking about? We’re
thinking about these goblins:
Figure 1: Cute goblin with a beret. Illustrated by Chris
Webber¶
Figure 2: Snuggly goblin. Illustrated by Karen Rustad¶
Those are pretty cute goblins. Those are the kinds of goblins
we’re thinking about.
Chris started doing work on the project after thinking about it
for a year. Then, after talking with Matt and Rob, it became an
official GNU project. Thus we now call it GNU MediaGoblin.
That’s a lot of letters, though, so in the interest of brevity and
facilitating easier casual conversation and balancing that with
what’s important to us, we have the following rules:
“GNU MediaGoblin” is the name we’re going to use in all official
capacities: web site, documentation, press releases, …
In casual conversation, it’s OK to use more casual names.
If you’re writing about the project, we ask that you call it GNU
MediaGoblin.
If you don’t like the name, we kindly ask you to take a deep
breath, think a happy thought about cute little goblins playing
on a playground and taking cute pictures of themselves, and let
it go. (Will added this one.)
Because I know Python, love Python, am capable of actually making
this thing happen in Python (I’ve worked on a lot of large free
software web applications before in Python, including Miro
Community, the Miro Guide, a large portion of Creative
Commons, and a whole bunch of things while working at Imaginary
Landscape). Me starting a project like this makes sense if it’s
done in Python.
You might say that PHP is way more deployable, that Rails has way
more cool developers riding around on fixie bikes—and all of
those things are true. But I know Python, like Python, and think
that Python is pretty great. I do think that deployment in Python
is not as good as with PHP, but I think the days of shared hosting
are (thankfully) coming to an end, and will probably be replaced
by cheap virtual machines spun up on the fly for people who want
that sort of stuff, and Python will be a huge part of that future,
maybe even more than PHP will. The deployment tools are getting
better. Maybe we can use something like Silver Lining. Maybe we
can just distribute as .debs or .rpms. We’ll figure it
out when we get there.
Regardless, if I’m starting this project, which I am, it’s gonna
be in Python.
If you notice in the technology list I list a lot of components
that are very “Django-like”, but not actually Django
components. What can I say, I really like a lot of the ideas in
Django! Which leads to the question: why not just use Django?
While I really like Django’s ideas and a lot of its components, I
also feel that most of the best ideas in Django I want have been
implemented as good or even better outside of Django. I could
just use Django and replace the templating system with Jinja2, and
the form system with wtforms, and the database with MongoDB and
MongoKit, but at that point, how much of Django is really left?
I also am sometimes saddened and irritated by how coupled all of
Django’s components are. Loosely coupled yes, but still coupled.
WSGI has done a good job of providing a base layer for running
applications on and if you know how to do it yourself [1], it’s
not hard or many lines of code at all to bind them together
without any framework at all (not even say Pylons, Pyramid
or Flask which I think are still great projects, especially for
people who want this sort of thing but have no idea how to get
started). And even at this already really early stage of writing
MediaGoblin, that glue work is mostly done.
Not to say I don’t think Django isn’t great for a lot of things.
For a lot of stuff, it’s still the best, but not for MediaGoblin,
I think.
One thing that Django does super well though is documentation. It
still has some faults, but even with those considered I can hardly
think of any other project in Python that has as nice of
documentation as Django. It may be worth learning some lessons on
documentation from Django [2], on that note.
I’d really like to have a good, thorough hacking-howto and
deployment-howto, especially in the former making some notes on
how to make it easier for Django hackers to get started.
(Note: We don’t use MongoDB anymore. This is the original rationale,
however.)
Chris Webber on “Why MongoDB”:
In case you were wondering, I am not a NOSQL fanboy, I do not go
around telling people that MongoDB is web scale. Actually my
choice for MongoDB isn’t scalability, though scaling up really
nicely is a pretty good feature and sets us up well in case large
volume sites eventually do use MediaGoblin. But there’s another
side of scalability, and that’s scaling down, which is important
for federation, maybe even more important than scaling up in an
ideal universe where everyone ran servers out of their own
housing. As a memory-mapped database, MongoDB is pretty hungry,
so actually I spent a lot of time debating whether the inability
to scale down as nicely as something like SQL has with SQLite
meant that it was out.
But I decided in the end that I really want MongoDB, not for
scalability, but for flexibility. Schema evolution pains in SQL
are almost enough reason for me to want MongoDB, but not quite.
The real reason is because I want the ability to eventually handle
multiple media types through MediaGoblin, and also allow for
plugins, without the rigidity of tables making that difficult. In
other words, something like:
{"title":"Me talking until you are bored","description":"blah blah blah","media_type":"audio","media_data":{"length":"2:30","codec":"OGG Vorbis"},"plugin_data":{"licensing":{"license":"http://creativecommons.org/licenses/by-sa/3.0/"}}}
Being able to just dump media-specific information in a media_data
hash table is pretty great, and even better is having a plugin
system where you can just let plugins have their own entire
key-value space cleanly inside the document that doesn’t interfere
with anyone else’s stuff. If we were to let plugins to deposit
their own information inside the database, either we’d let plugins
create their own tables which makes SQL migrations even harder
than they already are, or we’d probably end up creating a table
with a column for key, a column for value, and a column for type
in one huge table called “plugin_data” or something similar. (Yo
dawg, I heard you liked plugins, so I put a database in your
database so you can query while you query.) Gross.
I also don’t want things to be too loose so that we forget or lose
the structure of things, and that’s one reason why I want to use
MongoKit, because we can cleanly define a much structure as we
want and verify that documents match that structure generally
without adding too much bloat or overhead (MongoKit is a pretty
lightweight wrapper and doesn’t inject extra MongoKit-specific
stuff into the database, which is nice and nicer than many other
ORMs in that way).
Sphinx is a fantastic tool for organizing documentation for a
Python-based project that makes it pretty easy to write docs that
are readable in source form and can be “compiled” into HTML, LaTeX
and other formats.
There are other doc systems out there, but given that GNU
MediaGoblin is being written in Python and I’ve done a ton of
documentation using Sphinx, it makes sense to use Sphinx for now.
Chris, Brett, Will, Rob, Matt, et al curated into a story where
everyone is the hero by Will on “Why AGPLv3 and CC0”:
The AGPL v3 preserves the freedoms guaranteed by the GPL v3 in
the context of software as a service. Using this license ensures
that users of the service have the ability to examine the source,
deploy their own instance, and implement their own version. This
is really important to us and a core mission component of this
project. Thus we decided that the software parts should be under
this license.
However, the project is made up of more than just software:
there’s CSS, images, and other output-related things. We wanted
the templates/images/css side of the project all permissive and
permissive in the same absolutely permissive way. We’re waiving
our copyrights to non-software things under the CC0 waiver.
That brings us to the templates where there’s some code and some
output. The template engine we’re using is called Jinja2. It
mixes HTML markup with Python code to render the output of the
software. We decided the templates are part of the output of the
software and not the software itself. We wanted the output of the
software to be licensed in a hassle-free way so that when someone
deploys their own GNU MediaGoblin instance with their own
templates, they don’t have to deal with the copyleft aspects of
the AGPLv3 and we’d be fine with that because the changes they’re
making are identity-related. So at first we decided to waive our
copyrights to the templates with a CC0 waiver and then add an
exception to the AGPLv3 for the software such that the templates
can make calls into the software and yet be a separately licensed
work. However, Brett brought up the question of whether this
allows some unscrupulous person to make changes to the software
through the templates in such a way that they’re not bound by the
AGPLv3: i.e. a loophole. We thought about this loophole and
between this and the extra legalese involved in the exception to
the AGPLv3, we decided that it’s just way simpler if the templates
were also licensed under the AGPLv3.
Then we have the licensing for the documentation. Given that the
documentation is tied to the software content-wise, we don’t feel
like we have to worry about ensuring freedom of the documentation
or worry about attribution concerns. Thus we’re waiving our
copyrights to the documentation under CC0 as well.
Lastly, we have branding. This covers logos and other things that
are distinctive to GNU MediaGoblin that we feel represents this
project. Since we don’t currently have any branding, this is an
open issue, but we’re thinking we’ll go with a CC BY-SA license.
By licensing in this way, we make sure that users of the software
receive the freedoms that the AGPLv3 ensures regardless of what
fate befalls this project.
So to summarize:
software (Python, JavaScript, HTML templates): licensed
under AGPLv3
non-software things (CSS, images, video): copyrights waived
under CC0 because this is output of the software
documentation: copyrights waived under CC0 because it’s not part
of the software
branding assets: we’re kicking this can down the road, but
probably CC BY-SA
GNU MediaGoblin is a GNU project with non-mandatory but heavily
encouraged copyright assignment to the FSF. Most, if not all, of
the core contributors to GNU MediaGoblin will have done a
copyright assignment, but unlike some other GNU projects, it isn’t
required here. We think this is the best choice for GNU
MediaGoblin: it ensures that the Free Software Foundation may
protect the software by enforcing the AGPL if the FSF sees fit,
but it also means that we can immediately merge in changes from a
new contributor. It also means that some significant non-FSF
contributors might also be able to enforce the AGPL if seen fit.
Again, assignment is not mandatory, but it is heavily encouraged,
even incentivized: significant contributors who do a copyright
assignment to the FSF are eligible to have a unique goblin drawing
produced for them by the project’s main founder, Christopher Allan
Webber. See the wiki for details.
