Changes between Version 2 and Version 3 of TracModPython


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Timestamp:
Sep 11, 2019, 12:51:09 PM (5 years ago)
Author:
trac
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  • TracModPython

    v2 v3  
    1 = Trac and mod_python =
    21[[TracGuideToc]]
    32
     3= Trac and mod_python
     4
     5Mod_python is an [https://httpd.apache.org/ Apache] module that embeds the Python interpreter within the server, so that web-based applications in Python will run many times faster than traditional CGI and will have the ability to retain database connections.
    46Trac supports [http://www.modpython.org/ 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.
    57
    6 These instructions are for Apache 2; if you are still using Apache 1.3, you may have some luck with [trac:wiki:TracModPython2.7 TracModPython2.7].
    7 
    8 == A Word of Warning ==
    9 
    10 As of 16^th^ June 2010, the mod_python project is officially dead.  If you are considering using mod_python for a new installation, '''please don't'''!  There are known issues which will not be fixed and there are now better alternatives.  Check out the main TracInstall pages for your target version for more information.
    11 
    12 == Simple configuration ==
     8[[PageOutline(2-3,Overview,inline)]]
     9
     10== Simple configuration: single project #Simpleconfiguration
    1311
    1412If you just installed mod_python, you may have to add a line to load the module in the Apache configuration:
    15 {{{
     13{{{#!apache
    1614LoadModule python_module modules/mod_python.so
    1715}}}
    1816
    19 ''Note: The exact path to the module depends on how the HTTPD installation is laid out.''
    20 
    21 On Debian using apt-get
    22 {{{
     17'''Note''': The exact path to the module depends on how the HTTPD installation is laid out.
     18
     19On Debian using apt-get:
     20{{{#!sh
    2321apt-get install libapache2-mod-python libapache2-mod-python-doc
    2422}}}
    25 (Still on Debian) after you have installed mod_python, you must enable the modules in apache2 (equivalent of the above Load Module directive):
    26 {{{
     23
     24Still on Debian, after you have installed mod_python, you must enable the modules in apache2, equivalent to the above Load Module directive:
     25{{{#!sh
    2726a2enmod python
    2827}}}
     28
    2929On Fedora use, using yum:
    30 {{{
     30{{{#!sh
    3131yum install mod_python
    3232}}}
    33 You 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+.
    34 {{{
    35 #!xml
     33
     34You 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+.
     35{{{#!apache
    3636<Location /mpinfo>
    37    SetHandler mod_python
    38    PythonInterpreter main_interpreter
    39    PythonHandler mod_python.testhandler
    40    Order allow,deny
    41    Allow from all
    42 </Location>
    43 }}}
    44 
    45 A simple setup of Trac on mod_python looks like this:
    46 {{{
    47 #!xml
    48 <Location /projects/myproject>
    49    SetHandler mod_python
    50    PythonInterpreter main_interpreter
    51    PythonHandler trac.web.modpython_frontend
    52    PythonOption TracEnv /var/trac/myproject
    53    PythonOption TracUriRoot /projects/myproject
    54    Order allow,deny
    55    Allow from all
    56 </Location>
    57 }}}
    58 
    59 The 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.
    60 
    61 The options available are
    62 {{{
    63     # For a single project
    64     PythonOption TracEnv /var/trac/myproject
    65     # For multiple projects
    66     PythonOption TracEnvParentDir /var/trac/myprojects
    67     # For the index of multiple projects
    68     PythonOption TracEnvIndexTemplate /srv/www/htdocs/trac/project_list_template.html
    69     # A space delimitted list, with a "," between key and value pairs.
    70     PythonOption TracTemplateVars key1,val1 key2,val2
    71     # Useful to get the date in the wanted order
    72     PythonOption TracLocale en_GB.UTF8
    73     # See description above       
    74     PythonOption TracUriRoot /projects/myproject
    75 }}}
    76 
    77 === Python Egg Cache ===
    78 
    79 Compressed python eggs like Genshi are normally extracted into a directory named `.python-eggs` in the users home directory. Since apache's home usually is not writable an alternate egg cache directory can be specified like this:
    80 {{{
    81 PythonOption PYTHON_EGG_CACHE /var/trac/myprojects/egg-cache
    82 }}}
    83 
    84 or you can uncompress the Genshi egg to resolve problems extracting from it.
    85 === Configuring Authentication ===
    86 
    87 Creating password files and configuring authentication works similar to the process for [wiki:TracCgi#AddingAuthentication CGI]:
    88 {{{
    89 #!xml
    90 <Location /projects/myproject/login>
    91   AuthType Basic
    92   AuthName "myproject"
    93   AuthUserFile /var/trac/myproject/.htpasswd
    94   Require valid-user
    95 </Location>
    96 }}}
    97 
    98 Configuration for mod_ldap authentication in Apache is a bit tricky (httpd 2.2.x and OpenLDAP: slapd 2.3.19)
    99 
    100 1. You need to load the following modules in Apache httpd.conf
    101 {{{
    102 LoadModule ldap_module modules/mod_ldap.so
    103 LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
    104 }}}
    105 
    106 2. Your httpd.conf also needs to look something like:
    107 
    108 {{{
    109 #!xml
    110 <Location /trac/>
    11137  SetHandler mod_python
    11238  PythonInterpreter main_interpreter
    113   PythonHandler trac.web.modpython_frontend
    114   PythonOption TracEnv /home/trac/
    115   PythonOption TracUriRoot /trac/
    116   Order deny,allow
    117   Deny from all
    118   Allow from 192.168.11.0/24
    119   AuthType Basic
    120   AuthName "Trac"
    121   AuthBasicProvider "ldap"
    122   AuthLDAPURL "ldap://127.0.0.1/dc=example,dc=co,dc=ke?uid?sub?(objectClass=inetOrgPerson)"
    123   authzldapauthoritative Off
    124   require valid-user
    125 </Location>
    126 }}}
    127 
    128 Or the LDAP interface to a Microsoft Active Directory:
    129 
    130 {{{
    131 #!xml
    132 <Location /trac/>
     39  PythonHandler mod_python.testhandler
     40  # For Apache 2.2
     41  <IfModule !mod_authz_core.c>
     42    Order allow,deny
     43    Allow from all
     44  </IfModule>
     45  # For Apache 2.4
     46  <IfModule mod_authz_core.c>
     47    Require all granted
     48  </IfModule>
     49</Location>
     50}}}
     51
     52A simple setup of Trac on mod_python looks like this:
     53{{{#!apache
     54<Location /projects/myproject>
    13355  SetHandler mod_python
    13456  PythonInterpreter main_interpreter
    135   PythonHandler trac.web.modpython_frontend
    136   PythonOption TracEnv /home/trac/
    137   PythonOption TracUriRoot /trac/
    138   Order deny,allow
    139   Deny from all
    140   Allow from 192.168.11.0/24
    141   AuthType Basic
    142   AuthName "Trac"
    143   AuthBasicProvider "ldap"
    144   AuthLDAPURL "ldap://adserver.company.com:3268/DC=company,DC=com?sAMAccountName?sub?(objectClass=user)"
    145   AuthLDAPBindDN       ldap-auth-user@company.com
    146   AuthLDAPBindPassword "the_password"
    147   authzldapauthoritative Off
    148   # require valid-user
    149   require ldap-group CN=Trac Users,CN=Users,DC=company,DC=com
    150 </Location>
    151 }}}
    152 
    153 Note 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.
    154 
    155 Note 2: Active Directory requires an authenticating user/password to access records (AuthLDAPBindDN and AuthLDAPBindPassword).
    156 
    157 Note 3: The directive "require ldap-group ..."  specifies an AD group whose members are allowed access.
    158 
    159 
    160 === Setting the Python Egg Cache ===
    161 
    162 If the Egg Cache isn't writeable by your Web server, you'll either have to change the permissions, or point Python to a location where Apache can write. This can manifest itself as a ''500 internal server error'' and/or a complaint in the syslog.
    163 
    164 {{{
    165 #!xml
     57  PythonHandler trac.web.modpython_frontend
     58  PythonOption TracEnv /var/trac/myproject
     59  PythonOption TracUriRoot /projects/myproject
     60  # For Apache 2.2
     61  <IfModule !mod_authz_core.c>
     62    Order allow,deny
     63    Allow from all
     64  </IfModule>
     65  # For Apache 2.4
     66  <IfModule mod_authz_core.c>
     67    Require all granted
     68  </IfModule>
     69</Location>
     70}}}
     71
     72The 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.
     73
     74The options available are:
     75{{{#!apache
     76# For a single project
     77PythonOption TracEnv /var/trac/myproject
     78
     79# For multiple projects
     80PythonOption TracEnvParentDir /var/trac/myprojects
     81
     82# For the index of multiple projects
     83PythonOption TracEnvIndexTemplate /srv/www/htdocs/trac/project_list_template.html
     84
     85# A space delimitted list, with a "," between key and value pairs.
     86PythonOption TracTemplateVars key1,val1 key2,val2
     87
     88# Useful to get the date in the wanted order
     89PythonOption TracLocale en_GB.UTF8
     90
     91# See description above       
     92PythonOption TracUriRoot /projects/myproject
     93}}}
     94
     95=== Python Egg Cache
     96
     97Compressed Python eggs like Genshi are normally extracted into a directory named `.python-eggs` in the users home directory. Since Apache's home usually is not writeable, an alternate egg cache directory can be specified like this:
     98{{{#!apache
     99PythonOption PYTHON_EGG_CACHE /var/trac/myprojects/egg-cache
     100}}}
     101
     102Or you can uncompress the Genshi egg to resolve problems extracting from it.
     103
     104=== Configuring Authentication
     105
     106See corresponding section in the [wiki:TracModWSGI#ConfiguringAuthentication] page.
     107
     108== Advanced Configuration
     109
     110=== Setting the Python Egg Cache
     111
     112If the Egg Cache isn't writeable by your Web server, you'll either have to change the permissions, or point Python to a location where Apache can write. This can manifest itself as a `500 internal server error` and/or a complaint in the syslog.
     113
     114{{{#!apache
    166115<Location /projects/myproject>
    167116  ...
     
    171120}}}
    172121
    173 
    174 === Setting the !PythonPath ===
    175 
    176 If 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:
    177 {{{
    178 #!xml
     122=== Setting the !PythonPath
     123
     124If the Trac installation isn't installed in your Python path, you will have to tell Apache where to find the Trac mod_python handler  using the `PythonPath` directive:
     125{{{#!apache
    179126<Location /projects/myproject>
    180127  ...
     
    186133Be careful about using the !PythonPath directive, and ''not'' `SetEnv PYTHONPATH`, as the latter won't work.
    187134
    188 == Setting up multiple projects ==
     135=== Setting up multiple projects
    189136
    190137The Trac mod_python handler supports a configuration option similar to Subversion's `SvnParentPath`, called `TracEnvParentDir`:
    191 {{{
    192 #!xml
     138{{{#!apache
    193139<Location /projects>
    194140  SetHandler mod_python
     
    203149
    204150If you don't want to have the subdirectory listing as your projects home page you can use a
    205 {{{
    206 #!xml
     151{{{#!apache
    207152<LocationMatch "/.+/">
    208153}}}
     
    211156
    212157You can also use the same authentication realm for all of the projects using a `<LocationMatch>` directive:
    213 {{{
    214 #!xml
     158{{{#!apache
    215159<LocationMatch "/projects/[^/]+/login">
    216160  AuthType Basic
     
    221165}}}
    222166
    223 == Virtual Host Configuration ==
    224 
    225 Below is the sample configuration required to set up your trac as a virtual server (i.e. when you access it at the URLs like
    226 !http://trac.mycompany.com):
    227 
    228 {{{
    229 #!xml
    230 <VirtualHost * >
     167=== Virtual Host Configuration
     168
     169Below is the sample configuration required to set up your Trac as a virtual server, ie when you access it at the URLs like
     170`http://trac.mycompany.com`:
     171
     172{{{#!apache
     173<VirtualHost *>
    231174    DocumentRoot /var/www/myproject
    232175    ServerName trac.mycompany.com
     
    248191
    249192This does not seem to work in all cases. What you can do if it does not:
    250  * Try using `<LocationMatch>` instead of `<Location>`
    251  * <Location /> may, in your server setup, refer to the complete host instead of simple the root of the server. This means that everything (including the login directory referenced below) will be sent to python and authentication does not work (i.e. you get the infamous Authentication information missing error). If this applies to you, try using a sub-directory for trac instead of the root (i.e. /web/ and /web/login instead of / and /login).
     193 * Try using `<LocationMatch>` instead of `<Location>`.
     194 * `<Location />` may, in your server setup, refer to the complete host instead of simple the root of the server. This means that everything (including the login directory referenced below) will be sent to Python and authentication does not work, ie you get the infamous Authentication information missing error. If this is the case, try using a sub-directory for Trac instead of the root, ie /web/ and /web/login instead of / and /login.
    252195 * Depending on apache's `NameVirtualHost` configuration, you may need to use `<VirtualHost *:80>` instead of `<VirtualHost *>`.
    253196
    254 For a virtual host that supports multiple projects replace "`TracEnv`" /var/trac/myproject with "`TracEnvParentDir`" /var/trac/
    255 
    256 Note: !DocumentRoot should not point to your Trac project env. As Asmodai wrote on #trac: "suppose there's a webserver bug that allows disclosure of !DocumentRoot they could then leech the entire Trac environment".
    257 
    258 == Troubleshooting ==
    259 
    260 In general, if you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option:
    261 {{{
    262 #!xml
     197For a virtual host that supports multiple projects replace `TracEnv /var/trac/myproject` with `TracEnvParentDir /var/trac`.
     198
     199'''Note''': !DocumentRoot should not point to your Trac project env. As Asmodai wrote on #trac: "suppose there's a webserver bug that allows disclosure of !DocumentRoot they could then leech the entire Trac environment".
     200
     201== Troubleshooting
     202
     203If you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option:
     204{{{#!apache
    263205<Location /projects/myproject>
    264206  ...
     
    269211For multiple projects, try restarting the server as well.
    270212
     213=== Login Not Working
     214
     215If you've used `<Location />` directive, it will override any other directives, as well as `<Location /login>`.
     216The workaround is to use negation expression as follows (for multi project setups):
     217{{{#!apache
     218#this one for other pages
     219<Location ~ "/*(?!login)">
     220   SetHandler mod_python
     221   PythonHandler trac.web.modpython_frontend
     222   PythonOption TracEnvParentDir /projects
     223   PythonOption TracUriRoot /
     224</Location>
     225
     226#this one for login page
     227<Location ~ "/[^/]+/login">
     228   SetHandler mod_python
     229   PythonHandler trac.web.modpython_frontend
     230   PythonOption TracEnvParentDir /projects
     231   PythonOption TracUriRoot /
     232
     233   #remove these if you don't want to force SSL
     234   RewriteEngine On
     235   RewriteCond %{HTTPS} off
     236   RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}
     237
     238   AuthType Basic
     239   AuthName "Trac"
     240   AuthUserFile /projects/.htpasswd
     241   Require valid-user
     242</Location>
     243}}}
     244
    271245=== Expat-related segmentation faults === #expat
    272246
    273247This problem will most certainly hit you on Unix when using Python 2.4.
    274 In Python 2.4, some version of Expat (an XML parser library written in C) is used,
    275 and if Apache is using another version, this results in segmentation faults.
    276 As Trac 0.11 is using Genshi, which will indirectly use Expat, that problem
    277 can now hit you even if everything was working fine before with Trac 0.10.
    278 
    279 See Graham Dumpleton's detailed [http://www.dscpl.com.au/wiki/ModPython/Articles/ExpatCausingApacheCrash explanation and workarounds] for the issue.
    280 
    281 === Form submission problems ===
     248In Python 2.4, some version of [http://expat.sourceforge.net/ Expat] (an XML parser library written in C) is used and if Apache is using another version, this results in segmentation faults.
     249As Trac 0.11 is using Genshi, which will indirectly use Expat, that problem can now hit you even if everything was working fine before with Trac 0.10. This problem has not been reported for Python 2.5+, so best to upgrade.
     250
     251=== Form submission problems
    282252
    283253If 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.
    284254
    285 === Problem with virtual host configuration ===
    286 
    287 If 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).
    288 
    289 Using <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.
    290 
    291 === Problem with zipped egg ===
    292 
    293 It's possible that your version of mod_python will not import modules from zipped eggs. If you encounter an `ImportError: No module named trac` in your Apache logs but you think everything is where it should be, this might be your problem. Look in your site-packages directory; if the Trac module appears as a ''file'' rather than a ''directory'', then this might be your problem. To rectify, try installing Trac using the `--always-unzip` option, like this:
    294 
    295 {{{
     255=== Problem with virtual host configuration
     256
     257If 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.
     258
     259Using <Location /> together with `SetHandler` resulted in having everything handled by mod_python, which leads to not being able to download any CSS or images/icons. Use <Location /trac> `SetHandler None` </Location> to circumvent the problem, though this may not be the most elegant solution.
     260
     261=== Problem with zipped egg
     262
     263It's possible that your version of mod_python will not import modules from zipped eggs. If you encounter an `ImportError: No module named trac` in your Apache logs but you think everything is where it should be, this might be your problem. Look in your site-packages directory; if the Trac module appears as a ''file'' rather than a ''directory'', then this might be your problem. To rectify this, try installing Trac using the `--always-unzip` option:
     264
     265{{{#!sh
    296266easy_install --always-unzip Trac-0.12b1.zip
    297267}}}
    298268
    299 === Using .htaccess ===
     269=== Using .htaccess
    300270
    301271Although 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.
    302272
    303 It 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. :)
    304 
    305 A success story: For me it worked out-of-box, with following trivial config:
    306 {{{
     273It 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.
     274
     275This also works out-of-box, with following trivial config:
     276{{{#!apache
    307277SetHandler mod_python
    308278PythonInterpreter main_interpreter
     
    317287}}}
    318288
    319 The `TracUriRoot` is obviously the path you need to enter to the browser to get to the trac (e.g. domain.tld/projects/trac)
    320 
    321 === Additional .htaccess help ===
    322 
    323 If you are using the .htaccess method you may have additional problems if your trac directory is inheriting .htaccess directives from another. This may also help to add to your .htaccess file:
    324 
    325 {{{
     289The `TracUriRoot` is obviously the path you need to enter to the browser to get to Trac, eg `domain.tld/projects/trac`.
     290
     291=== Additional .htaccess help
     292
     293If you are using the .htaccess method you may have additional problems if your Trac directory is inheriting .htaccess directives from another. This may also help to add to your .htaccess file:
     294
     295{{{#!apache
    326296<IfModule mod_rewrite.c>
    327297  RewriteEngine Off
     
    329299}}}
    330300
    331 
    332 === Win32 Issues ===
    333 If 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.
    334 
    335 
    336 === OS X issues ===
    337 
    338 When 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 [http://www.dscpl.com.au/projects/vampire/patches.html here].
    339 
    340 === SELinux issues ===
    341 
    342 If Trac reports something like: ''Cannot get shared lock on db.lock''
    343 The security context on the repository may need to be set:
    344 
    345 {{{
     301=== Platform specific issues
     302==== Win32 Issues
     303
     304If 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.
     305
     306==== OS X issues
     307
     308When 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, so please upgrade mod_python to fix this.
     309
     310==== SELinux issues
     311
     312If Trac reports something like: `Cannot get shared lock on db.lock`, then the security context on the repository may need to be set:
     313
     314{{{#!sh
    346315chcon -R -h -t httpd_sys_content_t PATH_TO_REPOSITORY
    347316}}}
    348317
    349 See also [http://subversion.tigris.org/faq.html#reposperms]
    350 
    351 === FreeBSD issues ===
    352 Pay 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.
    353 
    354 If 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 recommendable.
    355 The best option [http://modpython.org/pipermail/mod_python/2006-September/021983.html seems to be] adding to /usr/local/apache2/bin/ennvars the line
    356 
    357 {{{
     318See also [http://subversion.apache.org/faq.html#reposperms How do I set repository permissions correctly?]
     319
     320==== FreeBSD issues
     321
     322The FreeBSD ports have both the new and old versions of mod_python and SQLite, but earlier versions of pysqlite and mod_python won't integrate:
     323 * pysqlite requires threaded support in Python
     324 * mod_python requires a threadless install.
     325
     326Apache2 does not automatically support threads on FreeBSD. You could force thread support when running `./configure` for Apache, using `--enable-threads`, but this isn´t recommended.
     327The best option [http://modpython.org/pipermail/mod_python/2006-September/021983.html seems to be] adding to /usr/local/apache2/bin/ennvars the line:
     328
     329{{{#!sh
    358330export LD_PRELOAD=/usr/lib/libc_r.so
    359331}}}
    360332
    361 === Subversion issues ===
    362 
    363 If 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.)
    364 
    365 If 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`).
    366 
    367 You 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 [trac:#3371 #3371], in order to force the use of the main interpreter:
    368 {{{
     333==== Fedora 7 Issues
     334
     335Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython, but not for tracd.
     336
     337=== Subversion issues
     338
     339If 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. A better way is to add a link to the bindings in the Python `site-packages` directory, or create a `.pth` file in that directory.
     340
     341If this is not the case, it's possible that you are using Subversion libraries that are binary incompatible with the Apache ones and 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`).
     342
     343You 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. Version 3.2.8 ''should'' work, though it's probably better to use the workaround described in [trac:#3371 #3371], in order to force the use of the main interpreter:
     344{{{#!apache
    369345PythonInterpreter main_interpreter
    370346}}}
    371 This is anyway the recommended workaround for other well-known issues seen when using the Python bindings for Subversion within mod_python ([trac:#2611 #2611], [trac:#3455 #3455]). See in particular Graham Dumpleton's comment in [trac:comment:9:ticket:3455 #3455] explaining the issue.
    372 
    373 === Page layout issues ===
    374 
    375 If 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:
    376 {{{
    377 #!xml
     347
     348This is also the recommended workaround for other issues seen when using the Python bindings for Subversion within mod_python ([trac:#2611 #2611], [trac:#3455 #3455]). See in particular Graham Dumpleton's comment in [trac:comment:9:ticket:3455 #3455] explaining the issue.
     349
     350=== Page layout issues
     351
     352If 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:
     353{{{#!apache
    378354Alias /myproject/css "/usr/share/trac/htdocs/css"
    379355<Location /myproject/css>
     
    382358}}}
    383359
    384 Note: For the above configuration to have any effect it must be put after the configuration of your project root location, i.e. {{{<Location /myproject />}}}.
    385 
    386 Also, setting `PythonOptimize On` seems to mess up the page headers and footers, in addition to hiding the documentation for macros and plugins (see #Trac8956). Considering how little effect the option has, it is probably a good idea to leave it `Off`.
    387 
    388 === HTTPS issues ===
    389 
    390 If 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:
    391 {{{
    392 #!xml
    393 <VirtualHost * >
     360'''Note''': For the above configuration to have any effect it must be put after the configuration of your project root location, ie {{{<Location /myproject />}}}.
     361
     362**Note:** Do not enable python optimizations using the directive `PythonOptimize On`. When optimizations are enabled the page header/footer and documentation for macros and plugins will be hidden. An error will be raised in Trac 1.0.11 and later when optimizations are enabled.
     363
     364=== HTTPS issues
     365
     366If 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:
     367{{{#!apache
     368<VirtualHost *>
    394369    DocumentRoot /var/www/myproject
    395370    ServerName trac.mycompany.com
     
    399374}}}
    400375
    401 === Fedora 7 Issues ===
    402 Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython but not for tracd
    403 
    404 
    405 === Segmentation fault with php5-mhash or other php5 modules ===
    406 You 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 [http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=411487]
    407 
    408 Some people also have troubles when using php5 compiled with its own 3rd party libraries instead of system libraries. Check here [http://www.djangoproject.com/documentation/modpython/#if-you-get-a-segmentation-fault]
     376=== Segmentation fault with php5-mhash or other php5 modules
     377
     378You 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 [http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=411487 Debian bug report].
     379
     380Some people also have troubles when using PHP5 compiled with its own third party libraries instead of system libraries. Check [http://www.djangoproject.com/documentation/modpython/#if-you-get-a-segmentation-fault Django segmentation fault].
    409381
    410382----
    411 See also:  TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI],  [trac:TracNginxRecipe TracNginxRecipe]
     383See also: TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI], [trac:TracNginxRecipe]