Using MacPorts

Installation steps:

1. sudo port install apache2
2. sudo port install subversion +mod_dav_svn
3. sudo port install trac

Optional:

1. sudo port install mod_python25

Note that you must ensure that you have installed the right version of mod_python for the python version upon which trac depends. As of late August, 2007 this is python25, and thus you have to use mod_python25.

Also note that on Leopard with XCode 3.0 you might run into an error when you try to install mod_python25 using macports:

nih$ sudo port install mod_python25
--->  Fetching mod_python25
--->  Verifying checksum(s) for mod_python25
--->  Extracting mod_python25
--->  Configuring mod_python25
--->  Building mod_python25 with target all
Error: Target org.macports.build returned: shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_www_mod_python25/work/mod_python-3.3.1" && make all " returned error 2
Command output:
Compiling for DSO.

/opt/local/apache2/bin/apxs -I/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_www_mod_python25/work/mod_python-3.3.1/src/include -I/opt/local/apache2/include -I/opt/local/include/python2.5 -c mod_python.c _apachemodule.c requestobject.c tableobject.c util.c serverobject.c connobject.c filterobject.c hlist.c hlistobject.c finfoobject.c -L/opt/local/lib -Wl,-F/opt/local/Library/Frameworks -L/opt/local/lib/python2.5/config  -u _PyMac_Error   -L/opt/local/lib   -lm  -lpython2.5   -ldl                    
/opt/local/share/apr-1/build/libtool --silent --mode=compile /usr/bin/gcc-4.0 -prefer-pic -O2  -DDARWIN -DSIGPROCMASK_SETS_THREAD_MASK -no-cpp-precomp -I/opt/local/include -I/opt/local/apache2/include  -I/opt/local/include/apr-1   -I/opt/local/include/apr-1 -I/opt/local/include -I/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_www_mod_python25/work/mod_python-3.3.1/src/include -I/opt/local/apache2/include -I/opt/local/include/python2.5  -c -o mod_python.lo mod_python.c && touch mod_python.slo
libtool: compile: unable to infer tagged configuration
libtool: compile: specify a tag with `--tag'
apxs:Error: Command failed with rc=65536
.
make[1]: *** [mod_python.so] Error 1
make: *** [do_dso] Error 2

Error: Status 1 encountered during processing.

The fix (from ​here) seems to be to edit /opt/local/apache2/bin/apxs and change (near line 50):

$ltflags or $ltflags = "--silent";

to

$ltflags or $ltflags = "--silent --tag=CC";

Then re-run

sudo port install mod_python25

After installing mod_python you may need to add LoadModule python_module modules/mod_python.so to your httpd.conf file.

Here is the trac configuration from my httpd.conf

<VirtualHost *>
  #
  # recall that ServerName has to be a read DNS name and 
  # match your VirtualHost spec (esp. if you are running on a special port)
  #
  ServerName projects.<domain>.com

  DocumentRoot "/Projects/Trac"

  #
  # don't forget to give httpd permission to read your trac docs and your trac root!
  #
  <Directory "/opt/local/share/trac/htdocs/">
    Order allow,deny
    Allow from all
  </Directory>

  <Directory "/Projects/Trac">
    Order allow,deny
    Allow from all
  </Directory>

  #
  # trac mod_python configuration
  #

  # we must first indicate where the doc supplementary 
  # files are so that trac's internal documentation works
  #
  Alias /trachtdocs/ "/opt/local/share/trac/htdocs/"
  <Location /trac>
    # then we indicate that, for this location, mod_python is in use
    SetHandler mod_python
    PythonInterpreter main_interpreter

    # next, we indicate where the "main()" is for mod_python
    PythonHandler trac.web.modpython_frontend

    # and now we configure trac via a few mod_python env variables.
    PythonOption TracUriRoot "/trac"
    PythonOption TracEnvParentDir "/Projects/Trac"
  </Location>

  #
  # trac authenticates with URLs of the form .../login, 
  # so we must match appropriately according to our TracUriRoot above
  #
  <LocationMatch /trac/[[:alnum:]]+/login>
    # for this example, only basic file-based authentication is demonstrated, 
    # but don't forget that many rich forms of authentication are available
    # including LDAP, DBM, groupfile, etc.
    AuthType Basic
    AuthName "<domain's> Trac"
    AuthUserFile "/opt/local/etc/trac-auth-file"
    Require valid-user
  </LocationMatch>
</VirtualHost>

If you installed Subversion without Berkeley DB support

If you installed Subversion without Berkeley DB support and the rest as above you get an Trac error:

   TracError: Unsupported version control system "svn". Check that the Python bindings for "svn" are correctly installed.

The reason is that the Subversion python bindings have been installed with the Berkeley DB support.

Either start again and follow the above instructions exactly or fix as follows:

1. sudo port uninstall trac
2. sudo port uninstall subversion-python25bindings
3. sudo port install subversion-python25bindings +no_bdb
4. sudo port install trac