RE: Clearcase to Subversion conversion

Here is some more information on available tools for converting Clearcase VOBs to Subversion repositories:

1. http://www.unix-girl.com/cc2svn/

I would not suggest using this conversion tool. It makes no attempt to convert ClearCase labels and branches to Subversion tags and branches.

2. http://www.polarion.org?page=overview&project=svnimporter <http://www.polarion.org/?page=overview&project=svnimporter>

Version 1.1-M6 does not convert ClearCase labels to Subversion tags.

Version 1.1-M7 does make an attempt to convert ClearCase labels to Subversion tags. However, it has a serious problem converting ClearCase branches -- it only puts files on a branch if it was actually modified on that branch. It does not understand the concept in ClearCase of using a checkpoint label as the basis for a branch. (This is solved in tool # 3 below by using a "branchinfo file".)

This tool also suffers from the same problems described with the next tool...

3. http://fdd.com/software/cvs/

(with the idea of then using cvs2svn to convert the resulting CVS repository to Subversion...)

This tool's problems are described right on the website:

(begin quote) "Essentially, the script exports everything ClearCase allows from a snapshot view. Thus, deleted files are not exported. All revisions of every branch are exported, but only if the current snapshot has that element, since ClearCase excludes others from lshist. We had an example where the same filename was created on two branches so ClearCase considered them separate elements, thus lshist of one did not show the revisions of the other. Cc2cvs.pl exported only the revisions of whichever snapshot it was run it on. " (end quote)

Personally, I would really like to have the complete ClearCase VOB history converted to Subversion. That way, I'll feel more confident that I'll never have a need to refer back to our old ClearCase VOBs (especially since we are de-commissioning these servers). It turns out that ClearCase's "cleartool lshist" command *can* supply information for deleted files, and for files with the same name that are different elements. You just have to execute "cleartool lshist -all" instead. Unfortunately, you then also have to deal with all the complex issues regarding renamed/deleted files and different elements with the same name.

4. Our solution

We actually wrote a C++ program to perform a complete conversion of our ClearCase VOBs into Subversion repositories. I am currently attempting to secure permission from my employer to release the source code for this program to the Open Source community. I'll probably know more about this in a few weeks. So, this may be helpful to you if you're not in a hurry.

5. Any other ideas?

Let me know if anyone knows of other tools or methods to convert ClearCase VOBs into Subversion repositories. If no other tools exist, then it may improve my argument to make our program available to the Open Source community.

Brian

________________________________

From: Luiz Henrique dos Santos Cruz
Sent: Thursday, May 11, 2006 2:53 PM
To: Brian Roark
Subject: Clearcase to Svn

Hi,

  I saw your post at http://svn.haxx.se/users/archive-2006-05/0015.shtml, and i am trying to find this tool too. Do you find something? Have any idea?

My possible next steps:

- http://www.unix-girl.com/cc2svn/ (have you tested it? I´m not sure that this will work)

- http://fdd.com/software/cvs/ (2 way conversion ... to cvs and after to svn)

 -----Original Message-----
From: Honzik
Sent: Wednesday, May 03, 2006 11:36 AM
To: Brian Roark
Subject: Re: ClearCase to Subversion conversion

svnimporter for svn from Polarion (http://www.polarion.org).

(copy && paste from polarion website):

    * External tool cleartool is used to access the ClearCase repository

      (part of ClearCase installation)

    * The transformation preserves revisions, authors, commit messages

      and dates of commits

    * Transformation converts ClearCase branches to SVN branches

    * Transformation converts ClearCase labels to SVN tags

    * Logging (output to console, logging level) can be tuned in

      configuration file (using log4j configuration)

H.h.

Brian Roark wrote:

>

> Is there a real tool available to convert existing ClearCase VOBs into

> a Subversion repository (similar in theory to "cvs2svn")?

>

> I've seen a few tools available on the web that simply migrate a

> single branch (usually the "main" branch) from ClearCase to

> Subversion. But, I've found no tool that can properly convert complete

> ClearCase VOBs, including all branches and labels (tags).

>

> Anyone have any suggestions? Or, has anyone considered starting up a

> new OpenSource project to address this type of conversion?

>

 
Received on Fri May 12 17:52:31 2006