close Warning: Can't synchronize with repository "(default)" (Unsupported version control system "svn": No module named svn). Look in the Trac log for more information.

Changes between Initial Version and Version 1 of TracModPython

Dec 15, 2007, 12:51:54 AM (15 years ago)



  • TracModPython

    v1 v1  
     1= Trac and mod_python =
     4Trac supports [ mod_python], which speeds up Trac's response times considerably, especially compared to [TracCgi CGI], and permits use of many Apache features not possible with [wiki:TracStandalone tracd]/mod_proxy.
     6== Simple configuration ==
     8If you just installed mod_python, you may have to add a line to load the module in the Apache configuration:
     10LoadModule python_module modules/
     13 ''Note: The exact path to the module depends on how the HTTPD installation is laid out.''
     14On Debian using apt-get
     16apt-get install libapache2-mod-python libapache2-mod-python-doc
     18(Still on Debian) after you have installed mod_python, you must enable the modules in apache2 (equivalent of the above Load Module directive):
     20a2enmod mod_python
     22On Fedora use, using yum:
     24yum install mod_python
     26You can test your mod_python installation by adding the following to your httpd.conf.  You should remove this when you are done testing for security reasons. Note: mod_python.testhandler is only available in mod_python 3.2+.
     29<Location /mpinfo>
     30   SetHandler mod_python
     31   PythonInterpreter main_interpreter
     32   PythonHandler mod_python.testhandler
     36A simple setup of Trac on mod_python looks like this:
     39<Location /projects/myproject>
     40   SetHandler mod_python
     41   PythonInterpreter main_interpreter
     42   PythonHandler trac.web.modpython_frontend
     43   PythonOption TracEnv /var/trac/myproject
     44   PythonOption TracUriRoot /projects/myproject
     48The option '''`TracUriRoot`''' may or may not be necessary in your setup. Try your configuration without it; if the URLs produced by Trac look wrong, if Trac does not seem to recognize URLs correctly, or you get an odd "No handler matched request to..." error, add the '''`TracUriRoot`''' option.  You will notice that the `Location` and '''`TracUriRoot`''' have the same path.
     50=== Configuring Authentication ===
     52Creating password files and configuring authentication works similar to the process for [wiki:TracCgi#AddingAuthentication CGI]:
     55<Location /projects/myproject/login>
     56  AuthType Basic
     57  AuthName "myproject"
     58  AuthUserFile /var/trac/myproject/.htpasswd
     59  Require valid-user
     63Configuration for mod_ldap authentication in Apache is a bit tricky (httpd 2.2.x and OpenLDAP: slapd 2.3.19)
     651. You need to load the following modules in Apache httpd.conf
     67LoadModule ldap_module modules/
     68LoadModule authnz_ldap_module modules/
     712. Your httpd.conf also needs to look something like:
     75<Location /trac/>
     76  SetHandler mod_python
     77  PythonInterpreter main_interpreter
     78  PythonHandler trac.web.modpython_frontend
     79  PythonOption TracEnv /home/trac/
     80  PythonOption TracUriRoot /trac/
     81  Order deny,allow
     82  Deny from all
     83  Allow from
     84  AuthType Basic
     85  AuthName "Trac"
     86  AuthBasicProvider "ldap"
     87  AuthLDAPURL "ldap://,dc=co,dc=ke?uid?sub?(objectClass=inetOrgPerson)"
     88  authzldapauthoritative Off
     89  require valid-user
     93Or the LDAP interface to a Microsoft Active Directory:
     97<Location /trac/>
     98  SetHandler mod_python
     99  PythonInterpreter main_interpreter
     100  PythonHandler trac.web.modpython_frontend
     101  PythonOption TracEnv /home/trac/
     102  PythonOption TracUriRoot /trac/
     103  Order deny,allow
     104  Deny from all
     105  Allow from
     106  AuthType Basic
     107  AuthName "Trac"
     108  AuthBasicProvider "ldap"
     109  AuthLDAPURL "ldap://,DC=com?sAMAccountName?sub?(objectClass=user)"
     110  AuthLDAPBindDN
     111  AuthLDAPBindPassword "the_password"
     112  authzldapauthoritative Off
     113  # require valid-user
     114  require ldap-group CN=Trac Users,CN=Users,DC=company,DC=com
     118Note 1: This is the case where the LDAP search will get around the multiple OUs, conecting to Global Catalog Server portion of AD (Notice the port is 3268, not the normal LDAP 389). The GCS is basically a "flattened" tree which allows searching for a user without knowing to which OU they belong.
     120Note 2: Active Directory requires an authenticating user/password to access records (AuthLDAPBindDN and AuthLDAPBindPassword).
     122Note 3: The directive "require ldap-group ..."  specifies an AD group whose members are allowed access.
     126=== Setting the !PythonPath ===
     128If the Trac installation isn't installed in your Python path, you'll have to tell Apache where to find the Trac mod_python handler  using the `PythonPath` directive:
     131<Location /projects/myproject>
     132  ...
     133  PythonPath "sys.path + ['/path/to/trac']"
     134  ...
     138Be careful about using the !PythonPath directive, and ''not'' `SetEnv PYTHONPATH`, as the latter won't work.
     140== Setting up multiple projects ==
     142The Trac mod_python handler supports a configuration option similar to Subversion's `SvnParentPath`, called `TracEnvParentDir`:
     145<Location /projects>
     146  SetHandler mod_python
     147  PythonInterpreter main_interpreter
     148  PythonHandler trac.web.modpython_frontend
     149  PythonOption TracEnvParentDir /var/trac
     150  PythonOption TracUriRoot /projects
     154When you request the `/projects` URL, you will get a listing of all subdirectories of the directory you set as `TracEnvParentDir` that look like Trac environment directories. Selecting any project in the list will bring you to the corresponding Trac environment.
     156If you don't want to have the subdirectory listing as your projects home page you can use a
     159<LocationMatch "/.+/">
     162This will instruct Apache to use mod_python for all locations different from root while having the possibility of placing a custom home page for root in your !DocumentRoot folder.
     164You can also use the same authentication realm for all of the projects using a `<LocationMatch>` directive:
     167<LocationMatch "/projects/[^/]+/login">
     168  AuthType Basic
     169  AuthName "Trac"
     170  AuthUserFile /var/trac/.htpasswd
     171  Require valid-user
     175== Virtual Host Configuration ==
     177Below is the sample configuration required to set up your trac as a virtual server (i.e. when you access it at the URLs like
     182<VirtualHost * >
     183    DocumentRoot /var/www/myproject
     184    ServerName
     185    <Location />
     186        SetHandler mod_python
     187        PythonInterpreter main_interpreter
     188        PythonHandler trac.web.modpython_frontend
     189        PythonOption TracEnv /var/trac/myproject
     190        PythonOption TracUriRoot /
     191    </Location>
     192    <Location /login>
     193        AuthType Basic
     194        AuthName "MyCompany Trac Server"
     195        AuthUserFile /var/trac/myproject/.htpasswd
     196        Require valid-user
     197    </Location>
     201if you have issues with login try using `<LocationMatch>` instead of `<Location>`
     203For a virtual host that supports multiple projects replace "`TracEnv`" /var/trac/myproject with "`TracEnvParentDir`" /var/trac/
     205== Troubleshooting ==
     207In general, if you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option:
     210<Location /projects/myproject>
     211  ...
     212  PythonDebug on
     216For multiple projects, try restarting the server as well.
     218=== Form submission problems ===
     220If you're experiencing problems submitting some of the forms in Trac (a common problem is that you get redirected to the start page after submission), check whether your {{{DocumentRoot}}} contains a folder or file with the same path that you mapped the mod_python handler to. For some reason, mod_python gets confused when it is mapped to a location that also matches a static resource.
     222=== Problem with virtual host configuration ===
     224If the <Location /> directive is used, setting the `DocumentRoot` may result in a ''403 (Forbidden)'' error. Either remove the `DocumentRoot` directive, or make sure that accessing the directory it points is allowed (in a corresponding `<Directory>` block).
     226Using <Location /> together with `SetHandler` resulted in having everything handled by mod_python, which leads to not being able download any CSS or images/icons. I used <Location /trac> `SetHandler None` </Location> to circumvent the problem, though I do not know if this is the most elegant solution.
     228=== Using .htaccess ===
     230Although it may seem trivial to rewrite the above configuration as a directory in your document root with a `.htaccess` file, this does not work. Apache will append a "/" to any Trac URLs, which interferes with its correct operation.
     232It may be possible to work around this with mod_rewrite, but I failed to get this working. In all, it is more hassle than it is worth. Stick to the provided instructions. :)
     234=== Win32 Issues ===
     235If you run trac with mod_python < 3.2 on Windows, uploading attachments will '''not''' work. This problem is resolved in mod_python 3.1.4 or later, so please upgrade mod_python to fix this.
     238=== OS X issues ===
     240When using mod_python on OS X you will not be able to restart Apache using `apachectl restart`. This is apparently fixed in mod_python 3.2, but there's also a patch available for earlier versions [ here].
     242=== SELinux issues ===
     244If Trac reports something like: ''Cannot get shared lock on db.lock''
     245The security context on the repository may need to be set:
     248chcon -R -h -t httpd_sys_content_t PATH_TO_REPOSITORY
     251See also [[]]
     253=== FreeBSD issues ===
     254Pay attention to the version of the installed mod_python and sqlite packages. Ports have both the new and old ones, but earlier versions of pysqlite and mod_python won't integrate as the former requires threaded support in python, and the latter requires a threadless install.
     256If you compiled and installed apache2, apache wouldn´t support threads (cause it doesn´t work very well on FreeBSD). You could force thread support when running ./configure for apache, using --enable-threads, but this isn´t recomendable.
     257The best option [[ seems to be]] adding to /usr/local/apache2/bin/ennvars the line
     260export LD_PRELOAD=/usr/lib/
     263=== Subversion issues ===
     265If you get the following Trac Error `Unsupported version control system "svn"` only under mod_python, though it works well on the command-line and even with TracStandalone, chances are that you forgot to add the path to the Python bindings with the [TracModPython#ConfiguringPythonPath PythonPath] directive. (The better way is to add a link to the bindings in the Python `site-packages` directory, or create a `.pth` file in that directory.)
     267If this is not the case, it's possible that you're using Subversion libraries that are binary incompatible with the apache ones (an incompatibility of the `apr` libraries is usually the cause). In that case, you also won't be able to use the svn modules for Apache (`mod_dav_svn`).
     269You also need a recent version of `mod_python` in order to avoid a runtime error ({{{argument number 2: a 'apr_pool_t *' is expected}}}) due to the default usage of multiple sub-interpreters. 3.2.8 ''should'' work, though it's probably better to use the workaround described in #3371, in order to force the use of the main interpreter:
     271PythonInterpreter main_interpreter
     273This is anyway the recommended workaround for other well-known issues seen when using the Python bindings for Subversion within mod_python (#2611, #3455). See in particular Graham Dumpleton's comment in [comment:ticket:3455:9 #3455] explaining the issue.
     275=== Page layout issues ===
     277If the formatting of the Trac pages look weird chances are that the style sheets governing the page layout are not handled properly by the web server. Try adding the following lines to your apache configuration:
     280Alias /myproject/css "/usr/share/trac/htdocs/css"
     281<Location /myproject/css>
     282    SetHandler None
     286Note: For the above configuration to have any effect it must be put after the configuration of your project root location, i.e. {{{<Location /myproject />}}}.
     288=== HTTPS issues ===
     290If you want to run Trac fully under https you might find that it tries to redirect to plain http. In this case just add the following line to your apache configuration:
     293<VirtualHost * >
     294    DocumentRoot /var/www/myproject
     295    ServerName
     296    SetEnv HTTPS 1
     297    ....
     301=== Fedora 7 Issues ===
     302Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython but not for tracd
     305=== Segmentation fault with php5-mhash or other php5 modules ===
     306You may encounter segfaults (reported on debian etch) if php5-mhash module is installed. Try to remove it to see if this solves the problem. See debian bug report [[]]
     308Some people also have troubles when using php5 compiled with its own 3rd party libraries instead of system libraries. Check here [[]]
     311See also TracGuide, TracInstall, TracCgi, TracFastCgi