Following error was occurring:

An Exception Has Occurred
Python Traceback
 
Traceback (most recent call last):
  File "/usr/local/viewvc-1.1/lib/viewvc.py", line 4065, in main
    request.run_viewvc()
  File "/usr/local/viewvc-1.1/lib/viewvc.py", line 403, in run_viewvc
    self.view_func(self)
  File "/usr/local/viewvc-1.1/lib/viewvc.py", line 1662, in view_roots
    allroots = list_roots(request)
  File "/usr/local/viewvc-1.1/lib/viewvc.py", line 3922, in list_roots
    cfg.utilities, cfg.options.svn_config_dir)
  File "/usr/local/viewvc-1.1/lib/vclib/svn/__init__.py", line 53, in SubversionRepository
    import svn_repos
  File "/usr/local/viewvc-1.1/lib/vclib/svn/svn_repos.py", line 25, in ?
    from svn import fs, repos, core, client, delta
ImportError: No module named svn

Solution: You need to install python bindings for svn and may also need to install python-devel and python-subversion.

Step 1: Check whether SWIG library is installed in your system or not (most distribution already have):

$ rpm -qa | grep -i swig
swig-1.3.29-2.el5

Its there in my system, if you doesn’t get any output then install the library by using yum install swig or manually by from here.

Step 2: Install python bindings for SWIG. I assume you have subversion source avaialble with you. Untar the source and you will be able to find the bindings in /usr/src/subversion-1.6.1/subversion/bindings/swig/python directory.

$ cd /usr/src/subversion-1.6.1/
$ make swig-py
$ make check-swig-py		### Perform checks 
$ make install-swig-py

You may also need to install python-devel and python-subversion as mentioned by comments below but I didn’t required it. If you face any issue while this installation, pls check INSTALL file in /usr/src/subversion-1.6.1/subversion/bindings/swig directory to get further instructions, otherwise the library should be installed successfully and programs like ViewVC or other ones which requires swig python bindings should run fine.

Step 1. Download and install
Get the latest version of viewvc from here, when writing of this article the latest version was 1.2-dev. I’m using the development branch, you can use more stable. Untar it and start installation:

$ tar xzf viewvc-1.2-dev.tar.gz
$ cd viewvc-1.2-dev
$ ./viewvc-install

Step 2. Installation
Answer simple questions. Default choice is okay for normal operation.

Step 3. Update Config
Edit its config file which is self explanatory. Various options are there, you should read carefully and make use of. For basic working just update following options related to your Subversion server:

$ cd /usr/local/viewvc-1.2-dev/
$ vi viewvc.conf
svn_roots = cgi-bin: /svn/cgi-bin
root_parents = /svn : svn
default_root = cgi
root_as_url_component = 1

here, root_parents is directory which contains all you repositories. It can be avoided in case your repositories are spread over multiple locations. default_root is the name of repository(set in svn_roots) to be displayed by viewvc automatically.

Step 4. Update Apache
Open your httpd.conf file for Apache settings and write:

$ vi /etc/httpd/conf/httpd.conf
 
ScriptAlias /viewvc /usr/local/viewvc-1.2-dev/bin/cgi/viewvc.cgi
ScriptAlias /queryvc /usr/local/viewvc-1.2-dev/bin/cgi/query.cgi

We are making a scriptalias to access viewvc through running its cgi script. The second line, which make alias of query.cgi is optional but recommended. It enables you to search for repositories, branches, files in your cvs/subversion.

ViewVC should run fine now, but in case you still found that its throwing some exception/error something like something like No module named svn found , pls proceed to the solution which I’ve posted here.

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