Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Mail Systems
Eclipse Documentation

How To Guides
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Problem Solutions
Privacy Policy




Version Control with Subversion
Prev Home Next

Version Control with Subversion - Subversion and DeltaV

Subversion and DeltaV

The original WebDAV standard has been widely successful. Every modern computer operating system has a general WebDAV client built-in (details to follow), and a number of popular standalone applications are also able to speak WebDAV — Microsoft Office, Dreamweaver, and Photoshop to name a few. On the server end, the Apache webserver has been able to provide WebDAV services since 1998 and is considered the de-facto open-source standard. There are several other commercial WebDAV servers available, including Microsoft's own IIS.

DeltaV, unfortunately, has not been so successful. It's very difficult to find any DeltaV clients or servers. The few that do exist are relatively unknown commercial products, and thus it's very difficult to test interoperability. It's not entirely clear as to why DeltaV has remained stagnant. Some argue that the specification is just too complex, others argue that while WebDAV's features have mass appeal (even the least technical users appreciate network file-sharing), version control features aren't interesting or necessary for most users. Finally, some have argued that DeltaV remains unpopular because there's still no open-source server product which implements it.

When Subversion was still in its design phase, it seemed like a great idea to use Apache httpd as the main network server. It already had a module to provide WebDAV services. DeltaV was a relatively new specification. The hope was that the Subversion server module (mod_dav_svn) would eventually evolve into an open-source DeltaV reference implementation. Unfortunately, DeltaV has a very specific versioning model that doesn't quite line up with Subversion's model. Some concepts were mappable, others were not.

The upshot is that

  1. The Subversion client is not a fully-implemented DeltaV client.

    The client needs certain things from the server that DeltaV cannot provide, and thus is largely dependent on a number of Subversion-specific REPORT requests that only mod_dav_svn understands.

  2. mod_dav_svn is not a fully-implemented DeltaV server.

    Many portions of the DeltaV specification were irrelevant to Subversion, and thus left unimplemented.

There is still some debate in the developer community as to whether or not it's worthwhile to remedy either of these situations. It's fairly unrealistic to change Subversion's design to match DeltaV, so there's probably no way the client can ever learn to get everything it needs from a general DeltaV server. On the other hand, mod_dav_svn could be further developed to implement all of DeltaV, but it's hard to find motivation to do so—there are almost no DeltaV clients to interoperate with.

[an error occurred while processing this directive]
Version Control with Subversion
Prev Home Next

  Published under the terms of the Creative Commons License Design by Interspire