incubator-cvs mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Apache Wiki <>
Subject [Incubator Wiki] Update of "CatacombProposal" by MarkusLitz
Date Fri, 19 Sep 2008 08:01:22 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Incubator Wiki" for change notification.

The following page has been changed by MarkusLitz:

New page:
= Catacomb Proposal =

== Abstract ==
Catacomb is a WebDAV repository module for use with the Apache WebDAV module, mod_dav.

== Proposal ==
Apache mod_dav parses WebDAV and DeltaV protocol requests into operations on a repository
providing persistent storage of resources and their properties. The default repository for
mod_dav is provided by a separate module, mod_dav_fs, which stores resource bodies as files
in the filesystem, and stores properties in a (G)DBM database.

Catacomb provides a replacement for mod_dav_fs called mod_dav_repos that stores resources
and their properties in a relational database using mod_dbd from the apache project for database
abstraction. The primary advantage of this approach is the searching capabilities of the database
are used to implement the DASL protocol. Additionally, the database allows straightforward
implementation of the versioning capabilities of the DeltaV protocol.

By shifting to relational database technology, Catacomb is a platform that contains important
aspects of typical document management systems: the ability to store large numbers of documents,
and search over their metadata. Furthermore, it is possible (via source code modification)
to change the set of predefined properties stored in the main schema of the relational database.
Properties in the main schema are faster to search. 

== Background ==
Catacomb was initially developed at the University of California, Santa Cruz (UCSC) in 2002
headed by Prof. E. James Whitehead. Catacomb was designed as a reference implementations for
WebDAV search and locating DASL. Also, main pieces of the WebDAV-DeltaV protocol (RFC 3253)
support originated from this time.

Since 2006 major parts of the development come from the german aerospace center (DLR) and
Catacomb gained support for the access control protocol (RFC 3744) and database abstraction
with apache mod_dbd.

== Rationale ==

The maintainers and developers of Catacomb are interested in joining the Apache Software Foundation
for several reasons:

 * Apache has a widely recognized name, which will help Catacomb get an increased visibility
and acceptance.
 * It might open the door for sharing ideas or cooperation with other projects, such as mod_dav
or Jackrabbit.
 * Catacomb would like to benefit from Apache's infrastructure.

== Initial Goals ==
Though the bulk of catacombs initial development is complete and the server is running stable,
there are still some large areas for future development. Some areas we hope to focus on in

 * Finish of the Access Control Protocol extension
 * Building up an automated testing environment
 * Implementation of WebDAV transaction methods 

== Current Status ==

=== Meritocracy ===
The initial development was done at UCSC and released as Open Source software under the Apache
Software License. Since release, many developers have adopted the server and submitted significant
patches. Later, the DLR take care of the most modifications and changed the license in agreement
with all developers to ASL2. Large portions of the codebase are now managed by those most
familiar with and responsible for them. Any potentially controversial change is discussed
on the public mailing list ( and
good suggestions are frequently implemented.

=== Community ===
Catacomb is used in many organizations which are interested in the advancement of the catacomb
development. Many of these have at least one developer that joined the catacomb mailing list
and so the mailing list is the most important communication platform. The catacomb community
encourages suggestions and contributions from any potential user and developer.

=== Core Developers ===
The initial core developers will come from UCSC. Many of these developers are still interested
in the advancement of the project. Furthermore there are a lot more commiters from other companies
which supports catacomb for years now. There is at least one Apache Member together with one
other Apache committer.

=== Alignment ===
Catacomb is a module for Apaches Webserver. This is why Apache httpd is the most important
dependency for catacomb. And catacomb is also a particularly good fit for Apache due to integration
potential with other projects, specifically mod_dav and Jackrabbit.

== Known Risks ==

=== Orphaned products ===
Despite to its small number of committers, there is no risk of being orphaned. The project
now exists for several years and there is a constant core-community which have a long-term
interest in use and maintenance of the code. 

=== Inexperience with Open Source ===
Catacomb was started as an open source project in 2002. Many of the committers have experience
working on open source projects and there are also at least one developer which has experience
as committer on other Apache projects. 

=== Homogenous Developers ===
As mentiont above, the current list of committers includes developers from at least two different
companies plus many independent volunteers. 

=== Reliance on Salaried Developers ===
At this time, many of the code comes from different companies like the DLR. Because the DLR
is a research facility, many of the work is done by students working on their diploma thesis.

=== Relationships with Other Apache Products ===
At this time, the only dependency to other apache projects is apaches http server. Another
project which implements advanced parts of the WebDAV protocol is Slide/Jackrabbit. But this
two project have different objectives and a different target audience so that there is no
direct competition between these project. In contrast to that, the developers could learn
much from each other when implementing advanced protocol issues.

=== A Excessive Fascination with the Apache Brand ===
The catacomb project exist quite successful on their own and could continue on that path with
no problems at all. We expect the Apache brand could help to increase the visibility of the
project and so maybe more developers could be interested in the project.

== Documentation ==
 * The existing project page could be found here:
 * The Catacomb Architecture:
 * The Catacomb mailing list with archive:
 * The Old mailing list archive:

== Initial Source ==
The initial source was hosted at Since 2006 the project is hosted at tigris. The
svn repository could be found here:

== Source and Intellectual Property Submission Plan ==
The complete catacomb code is under apache software license 2. The complete codebase that
is hosted at Tigris will be contributed.

== External Dependencies ==
At this time, there are no external dependencies. 

== Cryptography ==

== Required Resources ==

=== Mailing Lists ===
 * catacomb-dev
 * catacomb-users
 * catacomb-commits

=== Subversion Directory ===
 * per usual ASF guidelines 

=== Issue Tracking ===
 * Bugzilla (??)

== Initial Committers ==
 * Jim Whitehead <ejw at> UCSC
 * Sung Kim <hunkim at> UCSC
 * Pan Kai <pankai at> UCSC
 * Markus Litz <markus.litz at> DLR
 * Steven Mohr <steven.mohr at> DLR
 * Tim Olsen <tolsen718 at> !LimeWire
 * Elias Sinderson <elias at>  UCSC
 * Chris Knight <Christopher.D.Knight at> NASA
 * Gianugo Rabellino <gianugo at> Apache
 * Ricardo Rocha <ricardo at> Apache

== Sponsors ==

=== Champion ===
 * Gianugo Rabellino <gianugo at> Apache

=== Nominated Mentors ===
 * Gianugo Rabellino <gianugo at> Apache
 * Markus Litz <markus.litz at> DLR

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message