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Changes between Version 1 and Version 2 of TracModPython


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Timestamp:
Jul 17, 2018, 2:10:14 PM (6 years ago)
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trac
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  • TracModPython

    v1 v2  
    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 {{{#!div class="important"
    7 ** A Word of Warning **
    8 
    9 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.
    10 }}}
    11 
    12 
    13 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], but you'll be totally on your own.
    14 
    158[[PageOutline(2-3,Overview,inline)]]
    169
    17 == Simple configuration: single project == #Simpleconfiguration
     10== Simple configuration: single project #Simpleconfiguration
    1811
    1912If you just installed mod_python, you may have to add a line to load the module in the Apache configuration:
    20 {{{
     13{{{#!apache
    2114LoadModule python_module modules/mod_python.so
    2215}}}
    2316
    24 ''Note: The exact path to the module depends on how the HTTPD installation is laid out.''
    25 
    26 On Debian using apt-get
    27 {{{
     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
    2821apt-get install libapache2-mod-python libapache2-mod-python-doc
    2922}}}
    30 (Still on Debian) after you have installed mod_python, you must enable the modules in apache2 (equivalent of the above Load Module directive):
    31 {{{
     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
    3226a2enmod python
    3327}}}
     28
    3429On Fedora use, using yum:
    35 {{{
     30{{{#!sh
    3631yum install mod_python
    3732}}}
    38 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+.
    39 {{{
    40 #!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
    4136<Location /mpinfo>
    42    SetHandler mod_python
    43    PythonInterpreter main_interpreter
    44    PythonHandler mod_python.testhandler
    45    Order allow,deny
    46    Allow from all
     37  SetHandler mod_python
     38  PythonInterpreter main_interpreter
     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>
    4749</Location>
    4850}}}
    4951
    5052A simple setup of Trac on mod_python looks like this:
    51 {{{
    52 #!xml
     53{{{#!apache
    5354<Location /projects/myproject>
    54    SetHandler mod_python
    55    PythonInterpreter main_interpreter
    56    PythonHandler trac.web.modpython_frontend
    57    PythonOption TracEnv /var/trac/myproject
    58    PythonOption TracUriRoot /projects/myproject
    59    Order allow,deny
    60    Allow from all
    61 </Location>
    62 }}}
    63 
    64 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.
    65 
    66 The options available are
    67 {{{
    68     # For a single project
    69     PythonOption TracEnv /var/trac/myproject
    70 
    71     # For multiple projects
    72     PythonOption TracEnvParentDir /var/trac/myprojects
    73 
    74     # For the index of multiple projects
    75     PythonOption TracEnvIndexTemplate /srv/www/htdocs/trac/project_list_template.html
    76 
    77     # A space delimitted list, with a "," between key and value pairs.
    78     PythonOption TracTemplateVars key1,val1 key2,val2
    79 
    80     # Useful to get the date in the wanted order
    81     PythonOption TracLocale en_GB.UTF8
    82 
    83     # See description above       
    84     PythonOption TracUriRoot /projects/myproject
    85 }}}
    86 
    87 === Python Egg Cache ===
    88 
    89 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:
    90 {{{
     55  SetHandler mod_python
     56  PythonInterpreter main_interpreter
     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
    9199PythonOption PYTHON_EGG_CACHE /var/trac/myprojects/egg-cache
    92100}}}
    93101
    94 or you can uncompress the Genshi egg to resolve problems extracting from it.
    95 
    96 === Configuring Authentication ===
     102Or you can uncompress the Genshi egg to resolve problems extracting from it.
     103
     104=== Configuring Authentication
    97105
    98106See corresponding section in the [wiki:TracModWSGI#ConfiguringAuthentication] page.
    99107
    100 
    101108== Advanced Configuration
    102109
    103 === Setting the Python Egg Cache ===
    104 
    105 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.
    106 
    107 {{{
    108 #!xml
     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
    109115<Location /projects/myproject>
    110116  ...
     
    114120}}}
    115121
    116 
    117 === Setting the !PythonPath ===
    118 
    119 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:
    120 {{{
    121 #!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
    122126<Location /projects/myproject>
    123127  ...
     
    129133Be careful about using the !PythonPath directive, and ''not'' `SetEnv PYTHONPATH`, as the latter won't work.
    130134
    131 === Setting up multiple projects ===
     135=== Setting up multiple projects
    132136
    133137The Trac mod_python handler supports a configuration option similar to Subversion's `SvnParentPath`, called `TracEnvParentDir`:
    134 {{{
    135 #!xml
     138{{{#!apache
    136139<Location /projects>
    137140  SetHandler mod_python
     
    146149
    147150If you don't want to have the subdirectory listing as your projects home page you can use a
    148 {{{
    149 #!xml
     151{{{#!apache
    150152<LocationMatch "/.+/">
    151153}}}
     
    154156
    155157You can also use the same authentication realm for all of the projects using a `<LocationMatch>` directive:
    156 {{{
    157 #!xml
     158{{{#!apache
    158159<LocationMatch "/projects/[^/]+/login">
    159160  AuthType Basic
     
    164165}}}
    165166
    166 === Virtual Host Configuration ===
    167 
    168 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
    169 !http://trac.mycompany.com):
    170 
    171 {{{
    172 #!xml
    173 <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 *>
    174174    DocumentRoot /var/www/myproject
    175175    ServerName trac.mycompany.com
     
    191191
    192192This does not seem to work in all cases. What you can do if it does not:
    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 (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.
    195195 * Depending on apache's `NameVirtualHost` configuration, you may need to use `<VirtualHost *:80>` instead of `<VirtualHost *>`.
    196196
    197 For 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 
    203 In general, if you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option:
    204 {{{
    205 #!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
    206205<Location /projects/myproject>
    207206  ...
     
    212211For multiple projects, try restarting the server as well.
    213212
    214 === Login Not Working ===
     213=== Login Not Working
     214
    215215If you've used `<Location />` directive, it will override any other directives, as well as `<Location /login>`.
    216216The workaround is to use negation expression as follows (for multi project setups):
    217 {{{
    218 #!xml
     217{{{#!apache
    219218#this one for other pages
    220219<Location ~ "/*(?!login)">
     
    223222   PythonOption TracEnvParentDir /projects
    224223   PythonOption TracUriRoot /
    225 
    226 </Location>
     224</Location>
     225
    227226#this one for login page
    228227<Location ~ "/[^/]+/login">
     
    247246
    248247This problem will most certainly hit you on Unix when using Python 2.4.
    249 In Python 2.4, some version of Expat (an XML parser library written in C) is used,
    250 and if Apache is using another version, this results in segmentation faults.
    251 As Trac 0.11 is using Genshi, which will indirectly use Expat, that problem
    252 can now hit you even if everything was working fine before with Trac 0.10.
    253 
    254 See Graham Dumpleton's detailed [http://www.dscpl.com.au/wiki/ModPython/Articles/ExpatCausingApacheCrash explanation and workarounds] for the issue.
    255 
    256 === 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
    257252
    258253If 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.
    259254
    260 === Problem with virtual host configuration ===
    261 
    262 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).
    263 
    264 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.
    265 
    266 === Problem with zipped egg ===
    267 
    268 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:
    269 
    270 {{{
     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
    271266easy_install --always-unzip Trac-0.12b1.zip
    272267}}}
    273268
    274 === Using .htaccess ===
     269=== Using .htaccess
    275270
    276271Although 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.
    277272
    278 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. :)
    279 
    280 A success story: For me it worked out-of-box, with following trivial config:
    281 {{{#!xml
     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
    282277SetHandler mod_python
    283278PythonInterpreter main_interpreter
     
    292287}}}
    293288
    294 The `TracUriRoot` is obviously the path you need to enter to the browser to get to the trac (e.g. domain.tld/projects/trac)
    295 
    296 === Additional .htaccess help ===
    297 
    298 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:
    299 
    300 {{{
     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
    301296<IfModule mod_rewrite.c>
    302297  RewriteEngine Off
     
    305300
    306301=== Platform specific issues
    307 ==== Win32 Issues ====
    308 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.
    309 
    310 
    311 ==== OS X issues ====
    312 
    313 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].
    314 
    315 ==== SELinux issues ====
    316 
    317 If Trac reports something like: ''Cannot get shared lock on db.lock''
    318 The security context on the repository may need to be set:
    319 
    320 {{{
     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
    321315chcon -R -h -t httpd_sys_content_t PATH_TO_REPOSITORY
    322316}}}
    323317
    324 See also [http://subversion.tigris.org/faq.html#reposperms]
    325 
    326 ==== FreeBSD issues ====
    327 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.
    328 
    329 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.
    330 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
    331 
    332 {{{
     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
    333330export LD_PRELOAD=/usr/lib/libc_r.so
    334331}}}
    335332
    336 
    337 ==== Fedora 7 Issues ====
    338 Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython but not for tracd
    339 
    340 
    341 === Subversion issues ===
    342 
    343 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.)
    344 
    345 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`).
    346 
    347 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:
    348 {{{
     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
    349345PythonInterpreter main_interpreter
    350346}}}
    351 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.
    352 
    353 === Page layout issues ===
    354 
    355 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:
    356 {{{
    357 #!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
    358354Alias /myproject/css "/usr/share/trac/htdocs/css"
    359355<Location /myproject/css>
     
    362358}}}
    363359
    364 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 />}}}.
    365 
    366 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`.
    367 
    368 === HTTPS issues ===
    369 
    370 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:
    371 {{{
    372 #!xml
    373 <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 *>
    374369    DocumentRoot /var/www/myproject
    375370    ServerName trac.mycompany.com
     
    379374}}}
    380375
    381 
    382 === Segmentation fault with php5-mhash or other php5 modules ===
    383 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]
    384 
    385 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].
    386381
    387382----
    388 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]