Changeset 37343 for wiki/pages/TracModPython
- Timestamp:
- 03/12/16 20:47:19 (6 years ago)
- File:
-
- 1 edited
Legend:
- Unmodified
- Added
- Removed
-
wiki/pages/TracModPython
r26484 r37343 1 = Trac and mod_python =2 1 [[TracGuideToc]] 3 2 3 = Trac and mod_python 4 5 Mod_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. 4 6 Trac 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. 5 7 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. 8 These instructions are for Apache 2. If you are using Apache 1.3, you may have some luck with [trac:wiki:TracModPython2.7 TracModPython2.7], but that is a deprecated setup. 14 9 15 10 [[PageOutline(2-3,Overview,inline)]] … … 18 13 19 14 If you just installed mod_python, you may have to add a line to load the module in the Apache configuration: 20 {{{ 15 {{{#!apache 21 16 LoadModule python_module modules/mod_python.so 22 17 }}} 23 18 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 {{{ 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 {{{#!sh 28 23 apt-get install libapache2-mod-python libapache2-mod-python-doc 29 24 }}} 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 {{{ 25 26 Still on Debian, after you have installed mod_python, you must enable the modules in apache2, equivalent to the above Load Module directive: 27 {{{#!sh 32 28 a2enmod python 33 29 }}} 30 34 31 On Fedora use, using yum: 35 {{{ 32 {{{#!sh 36 33 yum install mod_python 37 34 }}} 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 35 36 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+. 37 {{{#!apache 41 38 <Location /mpinfo> 42 39 SetHandler mod_python … … 49 46 50 47 A simple setup of Trac on mod_python looks like this: 51 {{{ 52 #!xml 48 {{{#!apache 53 49 <Location /projects/myproject> 54 50 SetHandler mod_python … … 62 58 }}} 63 59 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. 65 66 The options available are 67 {{{ 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 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 writablean alternate egg cache directory can be specified like this:90 {{{ 60 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. 61 62 The options available are: 63 {{{#!apache 64 # For a single project 65 PythonOption TracEnv /var/trac/myproject 66 67 # For multiple projects 68 PythonOption TracEnvParentDir /var/trac/myprojects 69 70 # For the index of multiple projects 71 PythonOption TracEnvIndexTemplate /srv/www/htdocs/trac/project_list_template.html 72 73 # A space delimitted list, with a "," between key and value pairs. 74 PythonOption TracTemplateVars key1,val1 key2,val2 75 76 # Useful to get the date in the wanted order 77 PythonOption TracLocale en_GB.UTF8 78 79 # See description above 80 PythonOption TracUriRoot /projects/myproject 81 }}} 82 83 === Python Egg Cache 84 85 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 writeable, an alternate egg cache directory can be specified like this: 86 {{{#!apache 91 87 PythonOption PYTHON_EGG_CACHE /var/trac/myprojects/egg-cache 92 88 }}} 93 89 94 or you can uncompress the Genshi egg to resolve problems extracting from it.95 96 === Configuring Authentication ===90 Or you can uncompress the Genshi egg to resolve problems extracting from it. 91 92 === Configuring Authentication 97 93 98 94 See corresponding section in the [wiki:TracModWSGI#ConfiguringAuthentication] page. 99 95 100 101 96 == Advanced Configuration 102 97 103 === 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 98 === Setting the Python Egg Cache 99 100 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. 101 102 {{{#!apache 109 103 <Location /projects/myproject> 110 104 ... … … 114 108 }}} 115 109 116 117 === 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 110 === Setting the !PythonPath 111 112 If 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: 113 {{{#!apache 122 114 <Location /projects/myproject> 123 115 ... … … 129 121 Be careful about using the !PythonPath directive, and ''not'' `SetEnv PYTHONPATH`, as the latter won't work. 130 122 131 === Setting up multiple projects ===123 === Setting up multiple projects 132 124 133 125 The Trac mod_python handler supports a configuration option similar to Subversion's `SvnParentPath`, called `TracEnvParentDir`: 134 {{{ 135 #!xml 126 {{{#!apache 136 127 <Location /projects> 137 128 SetHandler mod_python … … 146 137 147 138 If you don't want to have the subdirectory listing as your projects home page you can use a 148 {{{ 149 #!xml 139 {{{#!apache 150 140 <LocationMatch "/.+/"> 151 141 }}} … … 154 144 155 145 You can also use the same authentication realm for all of the projects using a `<LocationMatch>` directive: 156 {{{ 157 #!xml 146 {{{#!apache 158 147 <LocationMatch "/projects/[^/]+/login"> 159 148 AuthType Basic … … 164 153 }}} 165 154 166 === 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 * > 155 === Virtual Host Configuration 156 157 Below is the sample configuration required to set up your Trac as a virtual server, ie when you access it at the URLs like 158 `http://trac.mycompany.com`: 159 160 {{{#!apache 161 <VirtualHost *> 174 162 DocumentRoot /var/www/myproject 175 163 ServerName trac.mycompany.com … … 191 179 192 180 This 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).181 * Try using `<LocationMatch>` instead of `<Location>`. 182 * `<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. 195 183 * Depending on apache's `NameVirtualHost` configuration, you may need to use `<VirtualHost *:80>` instead of `<VirtualHost *>`. 196 184 197 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 185 For a virtual host that supports multiple projects replace `TracEnv /var/trac/myproject` with `TracEnvParentDir /var/trac`. 186 187 '''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". 188 189 == Troubleshooting 190 191 If you get server error pages, you can either check the Apache error log, or enable the `PythonDebug` option: 192 {{{#!apache 206 193 <Location /projects/myproject> 207 194 ... … … 212 199 For multiple projects, try restarting the server as well. 213 200 214 === Login Not Working === 201 === Login Not Working 202 215 203 If you've used `<Location />` directive, it will override any other directives, as well as `<Location /login>`. 216 204 The workaround is to use negation expression as follows (for multi project setups): 217 {{{ 218 #!xml 205 {{{#!apache 219 206 #this one for other pages 220 207 <Location ~ "/*(?!login)"> … … 223 210 PythonOption TracEnvParentDir /projects 224 211 PythonOption TracUriRoot / 225 226 </Location> 212 </Location> 213 227 214 #this one for login page 228 215 <Location ~ "/[^/]+/login"> … … 247 234 248 235 This 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 === 236 In 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. 237 As 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. 238 239 === Form submission problems 257 240 258 241 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 {{{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. 259 242 260 === 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 isthe 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 {{{ 243 === Problem with virtual host configuration 244 245 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. 246 247 Using <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. 248 249 === Problem with zipped egg 250 251 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 this, try installing Trac using the `--always-unzip` option: 252 253 {{{#!sh 271 254 easy_install --always-unzip Trac-0.12b1.zip 272 255 }}} 273 256 274 === Using .htaccess ===257 === Using .htaccess 275 258 276 259 Although 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. 277 260 278 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 workedout-of-box, with following trivial config:281 {{{#! xml261 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. 262 263 This also works out-of-box, with following trivial config: 264 {{{#!apache 282 265 SetHandler mod_python 283 266 PythonInterpreter main_interpreter … … 292 275 }}} 293 276 294 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 {{{ 277 The `TracUriRoot` is obviously the path you need to enter to the browser to get to Trac, eg `domain.tld/projects/trac`. 278 279 === Additional .htaccess help 280 281 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: 282 283 {{{#!apache 301 284 <IfModule mod_rewrite.c> 302 285 RewriteEngine Off … … 305 288 306 289 === 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 {{{ 290 ==== Win32 Issues 291 292 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. 293 294 ==== OS X issues 295 296 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, so please upgrade mod_python to fix this. 297 298 ==== SELinux issues 299 300 If Trac reports something like: `Cannot get shared lock on db.lock`, then the security context on the repository may need to be set: 301 302 {{{#!sh 321 303 chcon -R -h -t httpd_sys_content_t PATH_TO_REPOSITORY 322 304 }}} 323 305 324 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 {{{ 306 See also [http://subversion.apache.org/faq.html#reposperms How do I set repository permissions correctly?] 307 308 ==== FreeBSD issues 309 310 The 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: 311 * pysqlite requires threaded support in Python 312 * mod_python requires a threadless install. 313 314 Apache2 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. 315 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: 316 317 {{{#!sh 333 318 export LD_PRELOAD=/usr/lib/libc_r.so 334 319 }}} 335 320 336 337 ==== 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 {{{ 321 ==== Fedora 7 Issues 322 323 Make sure you install the 'python-sqlite2' package as it seems to be required for TracModPython, but not for tracd. 324 325 === Subversion issues 326 327 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. 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. 328 329 If 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`). 330 331 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. 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: 332 {{{#!apache 349 333 PythonInterpreter main_interpreter 350 334 }}} 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 335 336 This 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. 337 338 === Page layout issues 339 340 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: 341 {{{#!apache 358 342 Alias /myproject/css "/usr/share/trac/htdocs/css" 359 343 <Location /myproject/css> … … 362 346 }}} 363 347 364 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 * > 348 '''Note''': For the above configuration to have any effect it must be put after the configuration of your project root location, ie {{{<Location /myproject />}}}. 349 350 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, leave it `Off`. 351 352 === HTTPS issues 353 354 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: 355 {{{#!apache 356 <VirtualHost *> 374 357 DocumentRoot /var/www/myproject 375 358 ServerName trac.mycompany.com … … 379 362 }}} 380 363 381 382 === 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]364 === Segmentation fault with php5-mhash or other php5 modules 365 366 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 [http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=411487 Debian bug report]. 367 368 Some 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]. 386 369 387 370 ---- 388 See also: TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI], [trac:TracNginxRecipeTracNginxRecipe]371 See also: TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracFastCgi FastCGI], [trac:TracNginxRecipe]
Note: See TracChangeset
for help on using the changeset viewer.