Changes between Version 6 and Version 7 of TracModPython


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Timestamp:
03/07/18 16:17:30 (15 months ago)
Author:
trac
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  • TracModPython

    v6 v7  
    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 [wiki:TracModPython2.7 TracModPython2.7].
    7 
    8 == Simple configuration ==
     8[[PageOutline(2-3,Overview,inline)]]
     9
     10== Simple configuration: single project #Simpleconfiguration
    911
    1012If you just installed mod_python, you may have to add a line to load the module in the Apache configuration:
    11 {{{
     13{{{#!apache
    1214LoadModule python_module modules/mod_python.so
    1315}}}
    1416
    15 ''Note: The exact path to the module depends on how the HTTPD installation is laid out.''
    16 
    17 On Debian using apt-get
    18 {{{
     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
    1921apt-get install libapache2-mod-python libapache2-mod-python-doc
    2022}}}
    21 (Still on Debian) after you have installed mod_python, you must enable the modules in apache2 (equivalent of the above Load Module directive):
    22 {{{
    23 a2enmod mod_python
    24 }}}
     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
     26a2enmod python
     27}}}
     28
    2529On Fedora use, using yum:
    26 {{{
     30{{{#!sh
    2731yum install mod_python
    2832}}}
    29 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+.
    30 {{{
    31 #!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
    3236<Location /mpinfo>
    33    SetHandler mod_python
    34    PythonInterpreter main_interpreter
    35    PythonHandler mod_python.testhandler
    36 </Location>
    37 }}}
    38 
    39 A simple setup of Trac on mod_python looks like this:
    40 {{{
    41 #!xml
    42 <Location /projects/myproject>
    43    SetHandler mod_python
    44    PythonInterpreter main_interpreter
    45    PythonHandler trac.web.modpython_frontend
    46    PythonOption TracEnv /var/trac/myproject
    47    PythonOption TracUriRoot /projects/myproject
    48 </Location>
    49 }}}
    50 
    51 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.
    52 
    53 The options available are
    54 {{{
    55     # For a single project
    56     PythonOption TracEnv /var/trac/myproject
    57     # For multiple projects
    58     PythonOption TracEnvParentDir /var/trac/myprojects
    59     # For the index of multiple projects
    60     PythonOption TracEnvIndexTemplate /srv/www/htdocs/trac/project_list_template.html
    61     # A space delimitted list, with a "," between key and value pairs.
    62     PythonOption TracTemplateVars key1,val1 key2,val2
    63     # Useful to get the date in the wanted order
    64     PythonOption TracLocale en_GB.UTF8
    65     # See description above       
    66     PythonOption TracUriRoot /projects/myproject
    67 }}}
    68 
    69 === Python Egg Cache ===
    70 
    71 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:
    72 {{{
    73 PythonOption PYTHON_EGG_CACHE /var/trac/myprojects/egg-cache
    74 }}}
    75 
    76 === Configuring Authentication ===
    77 
    78 Creating password files and configuring authentication works similar to the process for [wiki:TracCgi#AddingAuthentication CGI]:
    79 {{{
    80 #!xml
    81 <Location /projects/myproject/login>
    82   AuthType Basic
    83   AuthName "myproject"
    84   AuthUserFile /var/trac/myproject/.htpasswd
    85   Require valid-user
    86 </Location>
    87 }}}
    88 
    89 Configuration for mod_ldap authentication in Apache is a bit tricky (httpd 2.2.x and OpenLDAP: slapd 2.3.19)
    90 
    91 1. You need to load the following modules in Apache httpd.conf
    92 {{{
    93 LoadModule ldap_module modules/mod_ldap.so
    94 LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
    95 }}}
    96 
    97 2. Your httpd.conf also needs to look something like:
    98 
    99 {{{
    100 #!xml
    101 <Location /trac/>
    10237  SetHandler mod_python
    10338  PythonInterpreter main_interpreter
    104   PythonHandler trac.web.modpython_frontend
    105   PythonOption TracEnv /home/trac/
    106   PythonOption TracUriRoot /trac/
    107   Order deny,allow
    108   Deny from all
    109   Allow from 192.168.11.0/24
    110   AuthType Basic
    111   AuthName "Trac"
    112   AuthBasicProvider "ldap"
    113   AuthLDAPURL "ldap://127.0.0.1/dc=example,dc=co,dc=ke?uid?sub?(objectClass=inetOrgPerson)"
    114   authzldapauthoritative Off
    115   require valid-user
    116 </Location>
    117 }}}
    118 
    119 Or the LDAP interface to a Microsoft Active Directory:
    120 
    121 {{{
    122 #!xml
    123 <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>
    12455  SetHandler mod_python
    12556  PythonInterpreter main_interpreter
    126   PythonHandler trac.web.modpython_frontend
    127   PythonOption TracEnv /home/trac/
    128   PythonOption TracUriRoot /trac/
    129   Order deny,allow
    130   Deny from all
    131   Allow from 192.168.11.0/24
    132   AuthType Basic
    133   AuthName "Trac"
    134   AuthBasicProvider "ldap"
    135   AuthLDAPURL "ldap://adserver.company.com:3268/DC=company,DC=com?sAMAccountName?sub?(objectClass=user)"
    136   AuthLDAPBindDN       ldap-auth-user@company.com
    137   AuthLDAPBindPassword "the_password"
    138   authzldapauthoritative Off
    139   # require valid-user
    140   require ldap-group CN=Trac Users,CN=Users,DC=company,DC=com
    141 </Location>
    142 }}}
    143 
    144 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.
    145 
    146 Note 2: Active Directory requires an authenticating user/password to access records (AuthLDAPBindDN and AuthLDAPBindPassword).
    147 
    148 Note 3: The directive "require ldap-group ..."  specifies an AD group whose members are allowed access.
    149 
    150 
    151 
    152 === Setting the !PythonPath ===
    153 
    154 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:
    155 {{{
    156 #!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
    157115<Location /projects/myproject>
    158116  ...
     117  PythonOption PYTHON_EGG_CACHE /tmp
     118  ...
     119</Location>
     120}}}
     121
     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
     126<Location /projects/myproject>
     127  ...
    159128  PythonPath "sys.path + ['/path/to/trac']"
    160129  ...
     
    164133Be careful about using the !PythonPath directive, and ''not'' `SetEnv PYTHONPATH`, as the latter won't work.
    165134
    166 == Setting up multiple projects ==
     135=== Setting up multiple projects
    167136
    168137The Trac mod_python handler supports a configuration option similar to Subversion's `SvnParentPath`, called `TracEnvParentDir`:
    169 {{{
    170 #!xml
     138{{{#!apache
    171139<Location /projects>
    172140  SetHandler mod_python
     
    181149
    182150If you don't want to have the subdirectory listing as your projects home page you can use a
    183 {{{
    184 #!xml
     151{{{#!apache
    185152<LocationMatch "/.+/">
    186153}}}
     
    189156
    190157You can also use the same authentication realm for all of the projects using a `<LocationMatch>` directive:
    191 {{{
    192 #!xml
     158{{{#!apache
    193159<LocationMatch "/projects/[^/]+/login">
    194160  AuthType Basic
     
    199165}}}
    200166
    201 == Virtual Host Configuration ==
    202 
    203 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
    204 !http://trac.mycompany.com):
    205 
    206 {{{
    207 #!xml
    208 <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 *>
    209174    DocumentRoot /var/www/myproject
    210175    ServerName trac.mycompany.com
     
    226191
    227192This does not seem to work in all cases. What you can do if it does not:
    228  * Try using `<LocationMatch>` instead of `<Location>`
    229  * <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).
    230 
    231 For a virtual host that supports multiple projects replace "`TracEnv`" /var/trac/myproject with "`TracEnvParentDir`" /var/trac/
    232 
    233 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".
    234 
    235 == Troubleshooting ==
    236 
    237 In general, if you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option:
    238 {{{
    239 #!xml
     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.
     195 * Depending on apache's `NameVirtualHost` configuration, you may need to use `<VirtualHost *:80>` instead of `<VirtualHost *>`.
     196
     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
    240205<Location /projects/myproject>
    241206  ...
     
    246211For multiple projects, try restarting the server as well.
    247212
     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
    248245=== Expat-related segmentation faults === #expat
    249246
    250247This problem will most certainly hit you on Unix when using Python 2.4.
    251 In Python 2.4, some version of Expat (an XML parser library written in C) is used,
    252 and if Apache is using another version, this results in segmentation faults.
    253 As Trac 0.11 is using Genshi, which will indirectly use Expat, that problem
    254 can now hit you even if everything was working fine before with Trac 0.10.
    255 
    256 See Graham Dumpleton's detailed [http://www.dscpl.com.au/wiki/ModPython/Articles/ExpatCausingApacheCrash explanation and workarounds] for the issue.
    257 
    258 === Form submission problems ===
    259 
    260 If 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 {{{
    261 DocumentRoot
    262 }}} 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.
    263 
    264 === Problem with virtual host configuration ===
    265 
    266 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).
    267 
    268 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.
    269 
    270 === Using .htaccess ===
     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
     252
     253If 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.
     254
     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
     266easy_install --always-unzip Trac-0.12b1.zip
     267}}}
     268
     269=== Using .htaccess
    271270
    272271Although 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.
    273272
    274 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. :)
    275 
    276 A success story: For me it worked out-of-box, with following trivial config:
    277 {{{
     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
    278277SetHandler mod_python
    279278PythonInterpreter main_interpreter
     
    288287}}}
    289288
    290 The TracUriRoot is obviously the path you need to enter to the browser to get to the trac (e.g. domain.tld/projects/trac)
    291 
    292 === Additional .htaccess help ===
    293 
    294 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:
    295 
    296 {{{
     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
    297296<IfModule mod_rewrite.c>
    298297  RewriteEngine Off
     
    300299}}}
    301300
    302 
    303 === Win32 Issues ===
    304 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.
    305 
    306 
    307 === OS X issues ===
    308 
    309 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].
    310 
    311 === SELinux issues ===
    312 
    313 If Trac reports something like: ''Cannot get shared lock on db.lock''
    314 The security context on the repository may need to be set:
    315 
    316 {{{
     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
    317315chcon -R -h -t httpd_sys_content_t PATH_TO_REPOSITORY
    318316}}}
    319317
    320 See also [[http://subversion.tigris.org/faq.html#reposperms]]
    321 
    322 === FreeBSD issues ===
    323 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.
    324 
    325 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.
    326 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
    327 
    328 {{{
     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
    329330export LD_PRELOAD=/usr/lib/libc_r.so
    330331}}}
    331332
    332 === Subversion issues ===
    333 
    334 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.)
    335 
    336 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`).
    337 
    338 You also need a recent version of `mod_python` in order to avoid a runtime error ({{{
    339 argument number 2: a 'apr_pool_t *' is expected
    340 }}}) 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:
    341 {{{
     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
    342345PythonInterpreter main_interpreter
    343346}}}
    344 This 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.
    345 
    346 === Page layout issues ===
    347 
    348 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:
    349 {{{
    350 #!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
    351354Alias /myproject/css "/usr/share/trac/htdocs/css"
    352355<Location /myproject/css>
     
    355358}}}
    356359
    357 Note: For the above configuration to have any effect it must be put after the configuration of your project root location, i.e. {{{
    358 <Location /myproject />
    359 }}}.
    360 
    361 === HTTPS issues ===
    362 
    363 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:
    364 {{{
    365 #!xml
    366 <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 *>
    367369    DocumentRoot /var/www/myproject
    368370    ServerName trac.mycompany.com
     
    372374}}}
    373375
    374 === Fedora 7 Issues ===
    375 Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython but not for tracd
    376 
    377 
    378 === Segmentation fault with php5-mhash or other php5 modules ===
    379 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]]
    380 
    381 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].
    382381
    383382----
    384 See also:  TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe]
    385 
     383See also: TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI], [trac:TracNginxRecipe]