Changes between Version 3 and Version 4 of TracModWSGI


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Timestamp:
Jan 12, 2016, 11:21:52 PM (4 years ago)
Author:
trac
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  • TracModWSGI

    v3 v4  
    1 = Trac and mod_wsgi
    2 
    3 [https://github.com/GrahamDumpleton/mod_wsgi mod_wsgi] is an Apache module for running WSGI-compatible Python applications directly on top of the Apache webserver. The mod_wsgi adapter is written completely in C and provides very good performance.
     1= Trac and mod_wsgi =
     2
     3
     4[http://code.google.com/p/modwsgi/ mod_wsgi] is an Apache module for running WSGI-compatible Python applications directly on top of the Apache webserver. The mod_wsgi adapter is written completely in C and provides very good performances.
    45
    56[[PageOutline(2-3,Overview,inline)]]
     
    78== The `trac.wsgi` script
    89
    9 Trac can be run on top of mod_wsgi with the help of an application script, which is just a Python file saved with a `.wsgi` extension.
    10 
    11 A robust and generic version of this file can be created using the `trac-admin <env> deploy <dir>` command which automatically substitutes the required paths, see TracInstall#cgi-bin. The script should be sufficient for most installations and users not wanting more information can proceed to [#Mappingrequeststothescript configuring Apache].
    12 
    13 If you are using Trac with multiple projects, you can specify their common parent directory using the `TRAC_ENV_PARENT_DIR` in trac.wsgi:
    14 {{{#!python
    15 def application(environ, start_request):
    16     # Add this to config when you have multiple projects                                             
    17     environ.setdefault('trac.env_parent_dir', '/usr/share/trac/projects') 
    18     ..
    19 }}}
     10Trac can be run on top of mod_wsgi with the help of the following application script, which is just a Python file, though usually saved with a `.wsgi` extension).
    2011
    2112=== A very basic script
     
    3223}}}
    3324
    34 The `TRAC_ENV` variable should naturally be the directory for your Trac environment, and the `PYTHON_EGG_CACHE` should be a directory where Python can temporarily extract Python eggs. If you have several Trac environments in a directory, you can also use `TRAC_ENV_PARENT_DIR` instead of `TRAC_ENV`.
    35 
    36 On Windows:
    37  - If run under the user's session, the Python Egg cache can be found in `%AppData%\Roaming`, for example:
    38 {{{#!python
    39 os.environ['PYTHON_EGG_CACHE'] = r'C:\Users\Administrator\AppData\Roaming\Python-Eggs'
    40 }}}
    41  - If run under a Window service, you should create a directory for Python Egg cache:
    42 {{{#!python
    43 os.environ['PYTHON_EGG_CACHE'] = r'C:\Trac-Python-Eggs'
    44 }}}
     25The `TRAC_ENV` variable should naturally be the directory for your Trac environment (if you have several Trac environments in a directory, you can also use `TRAC_ENV_PARENT_DIR` instead), while the `PYTHON_EGG_CACHE` should be a directory where Python can temporarily extract Python eggs.
    4526
    4627=== A more elaborate script
    4728
    48 If you are using multiple `.wsgi` files (for example one per Trac environment) you must ''not'' use `os.environ['TRAC_ENV']` to set the path to the Trac environment. Using this method may lead to Trac delivering the content of another Trac environment, as the variable may be filled with the path of a previously viewed Trac environment.
     29If you're using multiple `.wsgi` files (for example one per Trac environment) you must ''not'' use `os.environ['TRAC_ENV']` to set the path to the Trac environment. Using this method may lead to Trac delivering the content of another Trac environment, as the variable may be filled with the path of a previously viewed Trac environment.
    4930
    5031To solve this problem, use the following `.wsgi` file instead:
     
    6243For clarity, you should give this file a `.wsgi` extension. You should probably put the file in its own directory, since you will expose it to Apache.
    6344
    64 If you have installed Trac and Python eggs in a path different from the standard one, you should add that path by adding the following code at the top of the wsgi script:
     45If you have installed Trac and eggs in a path different from the standard one you should add that path by adding the following code at the top of the wsgi script:
    6546
    6647{{{#!python
     
    7152Change it according to the path you installed the Trac libs at.
    7253
     54=== Recommended `trac.wsgi` script
     55
     56A somewhat robust and generic version of this file can be created using the `trac-admin <env> deploy <dir>` command which automatically substitutes the required paths (see TracInstall#cgi-bin).
     57
     58
    7359== Mapping requests to the script
    7460
    75 After preparing your .wsgi script, add the following to your Apache configuration file, typically `httpd.conf`:
    76 
    77 {{{#!apache
     61After you've done preparing your .wsgi script, add the following to your Apache configuration file (`httpd.conf` for example).
     62
     63{{{
    7864WSGIScriptAlias /trac /usr/local/trac/mysite/apache/mysite.wsgi
    7965
    8066<Directory /usr/local/trac/mysite/apache>
    8167    WSGIApplicationGroup %{GLOBAL}
    82     # For Apache 2.2
    83     <IfModule !mod_authz_core.c>
    84         Order deny,allow
    85         Allow from all
    86     </IfModule>
    87     # For Apache 2.4
    88     <IfModule mod_authz_core.c>
    89         Require all granted
    90     </IfModule>
     68    Order deny,allow
     69    Allow from all
    9170</Directory>
    9271}}}
     
    9473Here, the script is in a subdirectory of the Trac environment.
    9574
    96 If you followed the directions [TracInstall#cgi-bin Generating the Trac cgi-bin directory], your Apache configuration file should look like following:
    97 
    98 {{{#!apache
     75If you followed the directions [http://trac.edgewall.org/wiki/TracInstall#cgi-bin Generating the Trac cgi-bin directory], your Apache configuration file should look like following:
     76
     77{{{
    9978WSGIScriptAlias /trac /usr/share/trac/cgi-bin/trac.wsgi
    10079
    10180<Directory /usr/share/trac/cgi-bin>
    10281    WSGIApplicationGroup %{GLOBAL}
    103     # For Apache 2.2
    104     <IfModule !mod_authz_core.c>
    105         Order deny,allow
    106         Allow from all
    107     </IfModule>
    108     # For Apache 2.4
    109     <IfModule mod_authz_core.c>
    110         Require all granted
    111     </IfModule>
     82    Order deny,allow
     83    Allow from all
    11284</Directory>
    11385}}}
    11486
    115 In order to let Apache run the script, access to the directory in which the script resides is opened up to all of Apache. Additionally, the `WSGIApplicationGroup` directive ensures that Trac is always run in the first Python interpreter created by mod_wsgi. This is necessary because the Subversion Python bindings, which are used by Trac, don't always work in other sub-interpreters and may cause requests to hang or cause Apache to crash. After adding this configuration, restart Apache, and then it should work.
     87In order to let Apache run the script, access to the directory in which the script resides is opened up to all of Apache. Additionally, the `WSGIApplicationGroup` directive ensures that Trac is always run in the first Python interpreter created by mod_wsgi; this is necessary because the Subversion Python bindings, which are used by Trac, don't always work in other sub-interpreters and may cause requests to hang or cause Apache to crash as a result. After adding this configuration, restart Apache, and then it should work.
    11688
    11789To test the setup of Apache, mod_wsgi and Python itself (ie. without involving Trac and dependencies), this simple wsgi application can be used to make sure that requests gets served (use as only content in your `.wsgi` script):
     
    12597For more information about using the mod_wsgi specific directives, see the [http://code.google.com/p/modwsgi/wiki/ mod_wsgi's wiki] and more specifically the [http://code.google.com/p/modwsgi/wiki/IntegrationWithTrac IntegrationWithTrac] page.
    12698
     99
    127100== Configuring Authentication
    128101
    129 The following sections describe different methods for setting up authentication. See also [http://httpd.apache.org/docs/2.2/howto/auth.html Authentication, Authorization and Access Control] in the Apache guide.
    130 
    131 === Using Basic Authentication
    132 
    133 The simplest way to enable authentication with Apache is to create a password file. Use the `htpasswd` program as follows:
    134 {{{#!sh
     102We describe in the the following sections different methods for setting up authentication.
     103
     104See also [http://httpd.apache.org/docs/2.2/howto/auth.html Authentication, Authorization and Access Control] in the Apache guide.
     105
     106=== Using Basic Authentication ===
     107
     108The simplest way to enable authentication with Apache is to create a password file. Use the `htpasswd` program to create the password file:
     109{{{
    135110$ htpasswd -c /somewhere/trac.htpasswd admin
    136111New password: <type password>
     
    139114}}}
    140115
    141 After the first user, you don't need the "-c" option anymore:
    142 {{{#!sh
     116After the first user, you dont need the "-c" option anymore:
     117{{{
    143118$ htpasswd /somewhere/trac.htpasswd john
    144119New password: <type password>
     
    151126After you've created the users, you can set their permissions using TracPermissions.
    152127
    153 Now, you need to enable authentication against the password file in the Apache configuration:
    154 {{{#!apache
     128Now, you'll need to enable authentication against the password file in the Apache configuration:
     129{{{
    155130<Location "/trac/login">
    156131  AuthType Basic
     
    161136}}}
    162137
    163 If you are hosting multiple projects, you can use the same password file for all of them:
    164 {{{#!apache
     138If you're hosting multiple projects you can use the same password file for all of them:
     139{{{
    165140<LocationMatch "/trac/[^/]+/login">
    166141  AuthType Basic
     
    173148See also the [http://httpd.apache.org/docs/2.2/mod/mod_auth_basic.html mod_auth_basic] documentation.
    174149
    175 === Using Digest Authentication
     150=== Using Digest Authentication ===
    176151
    177152For better security, it is recommended that you either enable SSL or at least use the “digest” authentication scheme instead of “Basic”.
    178153
    179 You have to create your `.htpasswd` file with the `htdigest` command instead of `htpasswd`, as follows:
    180 {{{#!sh
    181 $ htdigest -c /somewhere/trac.htpasswd trac admin
     154You'll have to create your `.htpasswd` file with the `htdigest` command instead of `htpasswd`, as follows:
     155{{{
     156# htdigest -c /somewhere/trac.htpasswd trac admin
    182157}}}
    183158
    184159The "trac" parameter above is the "realm", and will have to be reused in the Apache configuration in the !AuthName directive:
    185160
    186 {{{#!apache
     161{{{
    187162<Location "/trac/login">
    188   AuthType Digest
    189   AuthName "trac"
    190   AuthDigestDomain /trac
    191   AuthUserFile /somewhere/trac.htpasswd
    192   Require valid-user
     163
     164    AuthType Digest
     165    AuthName "trac"
     166    AuthDigestDomain /trac
     167    AuthUserFile /somewhere/trac.htpasswd
     168    Require valid-user
    193169</Location>
    194170}}}
     
    196172For multiple environments, you can use the same `LocationMatch` as described with the previous method.
    197173
    198 '''Note: `Location` cannot be used inside .htaccess files, but must instead live within the main httpd.conf file. If you are on a shared server, you therefore will not be able to provide this level of granularity. '''
    199 
    200174Don't forget to activate the mod_auth_digest. For example, on a Debian 4.0r1 (etch) system:
    201 {{{#!apache
    202   LoadModule auth_digest_module /usr/lib/apache2/modules/mod_auth_digest.so
    203 }}}
     175{{{
     176    LoadModule auth_digest_module /usr/lib/apache2/modules/mod_auth_digest.so
     177}}}
     178
    204179
    205180See also the [http://httpd.apache.org/docs/2.2/mod/mod_auth_digest.html mod_auth_digest] documentation.
     
    207182=== Using LDAP Authentication
    208183
    209 Configuration for [http://httpd.apache.org/docs/2.2/mod/mod_ldap.html mod_ldap] authentication in Apache is more involved (httpd 2.2.x and OpenLDAP: slapd 2.3.19).
    210 
    211 1. You need to load the following modules in Apache httpd.conf:
    212 {{{#!apache
    213   LoadModule ldap_module modules/mod_ldap.so
    214   LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
    215 }}}
    216 1. Your httpd.conf also needs to look something like:
    217 {{{#!apache
     184Configuration for [http://httpd.apache.org/docs/2.2/mod/mod_ldap.html mod_ldap] authentication in Apache is a bit tricky (httpd 2.2.x and OpenLDAP: slapd 2.3.19)
     185
     1861. You need to load the following modules in Apache httpd.conf
     187{{{
     188LoadModule ldap_module modules/mod_ldap.so
     189LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
     190}}}
     191
     1922. Your httpd.conf also needs to look something like:
     193
     194{{{
    218195<Location /trac/>
    219196  # (if you're using it, mod_python specific settings go here)
     
    229206</Location>
    230207}}}
    231 1. You can use the LDAP interface as a way to authenticate to a Microsoft Active Directory. Use the following as your LDAP URL:
    232 {{{#!apache
    233   AuthLDAPURL "ldap://directory.example.com:3268/DC=example,DC=com?sAMAccountName?sub?(objectClass=user)"
    234 }}}
    235  You will also need to provide an account for Apache to use when checking credentials. As this password will be listed in plaintext in the config, you need to use an account specifically for this task:
    236 {{{#!apache
    237   AuthLDAPBindDN ldap-auth-user@example.com
    238   AuthLDAPBindPassword "password"
    239 }}}
    240  The whole section looks like:
    241 {{{#!apache
     208
     209
     2103. You can use the LDAP interface as a way to authenticate to a Microsoft Active Directory:
     211
     212
     213Use the following as your LDAP URL:
     214{{{
     215    AuthLDAPURL "ldap://directory.example.com:3268/DC=example,DC=com?sAMAccountName?sub?(objectClass=user)"
     216}}}
     217
     218You will also need to provide an account for Apache to use when checking
     219credentials. As this password will be listed in plaintext in the
     220config, you should be sure to use an account specifically for this task:
     221{{{
     222    AuthLDAPBindDN ldap-auth-user@example.com
     223    AuthLDAPBindPassword "password"
     224}}}
     225
     226The whole section looks like:
     227{{{
    242228<Location /trac/>
    243229  # (if you're using it, mod_python specific settings go here)
     
    253239  authzldapauthoritative Off
    254240  # require valid-user
    255   Require ldap-group CN=Trac Users,CN=Users,DC=company,DC=com
     241  require ldap-group CN=Trac Users,CN=Users,DC=company,DC=com
    256242</Location>
    257243}}}
    258244
    259 Note 1: This is the case where the LDAP search will get around the multiple OUs, conecting to the Global Catalog Server portion of AD. Note 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.
    260 
    261 Note 2: You can also require the user be a member of a certain LDAP group, instead of just having a valid login:
    262 {{{#!apache
    263   Require ldap-group CN=Trac Users,CN=Users,DC=example,DC=com
     245Note 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.
     246
     247Note 2: You can also require the user be a member of a certain LDAP group, instead of
     248just having a valid login:
     249{{{
     250    Require ldap-group CN=Trac Users,CN=Users,DC=example,DC=com
    264251}}}
    265252
    266253See also:
    267  - [http://httpd.apache.org/docs/2.2/mod/mod_authnz_ldap.html mod_authnz_ldap], documentation for mod_authnz_ldap.   
     254  - [http://httpd.apache.org/docs/2.2/mod/mod_authnz_ldap.html mod_authnz_ldap], documentation for mod_authnz_ldap
     255   
    268256 - [http://httpd.apache.org/docs/2.2/mod/mod_ldap.html mod_ldap], documentation for mod_ldap, which provides connection pooling and a shared cache.
    269257 - [http://trac-hacks.org/wiki/LdapPlugin TracHacks:LdapPlugin] for storing TracPermissions in LDAP.
     
    271259=== Using SSPI Authentication
    272260
    273 If you are using Apache on Windows, you can use mod_auth_sspi to provide single-sign-on. Download the module from the !SourceForge [http://sourceforge.net/projects/mod-auth-sspi/ mod-auth-sspi project] and then add the following to your !VirtualHost:
    274 {{{#!apache
    275 <Location /trac/login>
    276   AuthType SSPI
    277   AuthName "Trac Login"
    278   SSPIAuth On
    279   SSPIAuthoritative On
    280   SSPIDomain MyLocalDomain
    281   SSPIOfferBasic On
    282   SSPIOmitDomain Off
    283   SSPIBasicPreferred On
    284   Require valid-user
    285 </Location>
    286 }}}
    287 
    288 Using the above, usernames in Trac will be of the form `DOMAIN\username`, so you may have to re-add permissions and such. If you do not want the domain to be part of the username, set `SSPIOmitDomain On` instead.
     261If you are using Apache on Windows, you can use mod_auth_sspi to provide
     262single-sign-on. Download the module from the !SourceForge [http://sourceforge.net/projects/mod-auth-sspi/ mod-auth-sspi project] and then add the
     263following to your !VirtualHost:
     264{{{
     265    <Location /trac/login>
     266        AuthType SSPI
     267        AuthName "Trac Login"
     268        SSPIAuth On
     269        SSPIAuthoritative On
     270        SSPIDomain MyLocalDomain
     271        SSPIOfferBasic On
     272        SSPIOmitDomain Off
     273        SSPIBasicPreferred On
     274        Require valid-user
     275    </Location>
     276}}}
     277
     278Using the above, usernames in Trac will be of the form `DOMAIN\username`, so
     279you may have to re-add permissions and such. If you do not want the domain to
     280be part of the username, set `SSPIOmitDomain On` instead.
    289281
    290282Some common problems with SSPI authentication: [trac:#1055], [trac:#1168] and [trac:#3338].
     
    292284See also [trac:TracOnWindows/Advanced].
    293285
    294 === Using CA !SiteMinder Authentication
    295 Setup CA !SiteMinder to protect your Trac login URL (e.g. /trac/login).  Then modify the trac.wsgi script generated using `trac-admin <env> deploy <dir>` to add the following lines, which extract the HTTP_SM_USER variable and set it to REMOTE_USER:
    296 
    297 {{{#!python
    298 def application(environ, start_request):
    299     # Set authenticated username on CA SiteMinder to REMOTE_USER variable
    300     # strip() is used to remove any spaces on the end of the string
    301     if 'HTTP_SM_USER' in environ:
    302         environ['REMOTE_USER'] = environ['HTTP_SM_USER'].strip()
    303     ...
    304 }}}
    305 
    306 Note:  you do not need any Apache "Location" directives.
    307 
    308286=== Using Apache authentication with the Account Manager plugin's Login form ===
    309287
     
    313291
    314292Here is an example (from the !HttpAuthStore link) using acct_mgr-0.4 for hosting a single project:
    315 {{{#!ini
     293{{{
    316294[components]
    317295; be sure to enable the component
     
    324302}}}
    325303This will generally be matched with an Apache config like:
    326 {{{#!apache
     304{{{
    327305<Location /authFile>
    328306   …HTTP authentication configuration…
     
    330308</Location>
    331309}}}
    332 Note that '''authFile''' need not exist (unless you are using Account Manager older than 0.4). See the !HttpAuthStore link above for examples where multiple Trac projects are hosted on a server.
     310Note that '''authFile''' need not exist. See the !HttpAuthStore link above for examples where multiple Trac projects are hosted on a server.
    333311
    334312=== Example: Apache/mod_wsgi with Basic Authentication, Trac being at the root of a virtual host
    335313
    336 Per the mod_wsgi documentation linked to above, here is an example Apache configuration that:
    337  - serves the Trac instance from a virtualhost subdomain
    338  - uses Apache basic authentication for Trac authentication.
     314Per the mod_wsgi documentation linked to above, here is an example Apache configuration that a) serves the Trac instance from a virtualhost subdomain and b) uses Apache basic authentication for Trac authentication.
     315
    339316
    340317If you want your Trac to be served from e.g. !http://trac.my-proj.my-site.org, then from the folder e.g. `/home/trac-for-my-proj`, if you used the command `trac-admin the-env initenv` to create a folder `the-env`, and you used `trac-admin the-env deploy the-deploy` to create a folder `the-deploy`, then first:
    341318
    342319Create the htpasswd file:
    343 {{{#!sh
     320{{{
    344321cd /home/trac-for-my-proj/the-env
    345322htpasswd -c htpasswd firstuser
     
    347324htpasswd htpasswd seconduser
    348325}}}
    349 Keep the file above your document root for security reasons.
    350 
    351 Create this file e.g. (ubuntu) `/etc/apache2/sites-enabled/trac.my-proj.my-site.org.conf` with the following content:
    352 
    353 {{{#!apache
     326(keep the file above your document root for security reasons)
     327
     328Create this file e.g. (ubuntu) `/etc/apache2/sites-enabled/trac.my-proj.my-site.org.conf` with the following contents:
     329
     330{{{
    354331<Directory /home/trac-for-my-proj/the-deploy/cgi-bin/trac.wsgi>
    355332  WSGIApplicationGroup %{GLOBAL}
     
    374351Note: for subdomains to work you would probably also need to alter `/etc/hosts` and add A-Records to your host's DNS.
    375352
     353
    376354== Troubleshooting
    377355
    378356=== Use a recent version
    379357
    380 Please use either version 1.6, 2.4 or later of `mod_wsgi`. Versions prior to 2.4 in the 2.X branch have problems with some Apache configurations that use WSGI file wrapper extension. This extension is used in Trac to serve up attachments and static media files such as style sheets. If you are affected by this problem, attachments will appear to be empty and formatting of HTML pages will appear not to work due to style sheet files not loading properly. Another frequent symptom is that binary attachment downloads are truncated. See mod_wsgi tickets [http://code.google.com/p/modwsgi/issues/detail?id=100 #100] and [http://code.google.com/p/modwsgi/issues/detail?id=132 #132].
     358Please use either version 1.6, 2.4 or later of `mod_wsgi`. Versions prior to 2.4 in the 2.X branch have problems with some Apache configurations that use WSGI file wrapper extension. This extension is used in Trac to serve up attachments and static media files such as style sheets. If you are affected by this problem attachments will appear to be empty and formatting of HTML pages will appear not to work due to style sheet files not loading properly. Another frequent symptom is that binary attachment downloads are truncated. See mod_wsgi tickets [http://code.google.com/p/modwsgi/issues/detail?id=100 #100] and [http://code.google.com/p/modwsgi/issues/detail?id=132 #132].
    381359
    382360''Note: using mod_wsgi 2.5 and Python 2.6.1 gave an Internal Server Error on my system (Apache 2.2.11 and Trac 0.11.2.1). Upgrading to Python 2.6.2 (as suggested [http://www.mail-archive.com/modwsgi@googlegroups.com/msg01917.html here]) solved this for me[[BR]]-- Graham Shanks''
    383361
    384 If you plan to use `mod_wsgi` in embedded mode on Windows or with the MPM worker on Linux, then you will need version 3.4 or greater. See [trac:#10675] for details.
    385 
    386 === Getting Trac to work nicely with SSPI and 'Require Group'
    387 
    388 If you have set Trac up on Apache, Win32 and configured SSPI, but added a 'Require group' option to your apache configuration, then the SSPIOmitDomain option is probably not working. If it is not working, your usernames in Trac probably look like 'DOMAIN\user' rather than 'user'.
    389 
    390 This WSGI script 'fixes' that:
     362If you plan to use `mod_wsgi` in embedded mode on Windows or with the MPM worker on Linux, then you'll even need version 0.3.4 or greater (see [trac:#10675] for details).
     363
     364=== Getting Trac to work nicely with SSPI and 'Require Group' ===
     365If like me you've set Trac up on Apache, Win32 and configured SSPI, but added a 'Require group' option to your apache configuration, then the SSPIOmitDomain option is probably not working.  If its not working your usernames in trac are probably looking like 'DOMAIN\user' rather than 'user'.
     366
     367This WSGI script 'fixes' things, hope it helps:
    391368{{{#!python
    392369import os
     
    402379}}}
    403380
    404 === Trac with PostgreSQL
    405 
    406 When using the mod_wsgi adapter with multiple Trac instances and PostgreSQL (or MySQL?) as the database, the server ''may'' create a lot of open database connections and thus PostgreSQL processes.
    407 
    408 A somewhat brutal workaround is to disable connection pooling in Trac. This is done by setting `poolable = False` in `trac.db.postgres_backend` on the `PostgreSQLConnection` class.
    409 
    410 But it is not necessary to edit the source of Trac. The following lines in `trac.wsgi` will also work:
    411 
    412 {{{#!python
     381
     382=== Trac with PostgreSQL ===
     383
     384When using the mod_wsgi adapter with multiple Trac instances and PostgreSQL (or MySQL?) as a database back-end, the server ''may'' create a lot of open database connections and thus PostgreSQL processes.
     385
     386A somewhat brutal workaround is to disabled connection pooling in Trac. This is done by setting `poolable = False` in `trac.db.postgres_backend` on the `PostgreSQLConnection` class.
     387
     388But it's not necessary to edit the source of Trac, the following lines in `trac.wsgi` will also work:
     389
     390{{{
    413391import trac.db.postgres_backend
    414392trac.db.postgres_backend.PostgreSQLConnection.poolable = False
     
    417395or
    418396
    419 {{{#!python
     397{{{
    420398import trac.db.mysql_backend
    421399trac.db.mysql_backend.MySQLConnection.poolable = False
    422400}}}
    423401
    424 Now Trac drops the connection after serving a page and the connection count on the database will be kept low.
     402Now Trac drops the connection after serving a page and the connection count on the database will be kept minimal.
    425403
    426404//This is not a recommended approach though. See also the notes at the bottom of the [http://code.google.com/p/modwsgi/wiki/IntegrationWithTrac mod_wsgi's IntegrationWithTrac] wiki page.//
     
    430408For more troubleshooting tips, see also the [TracModPython#Troubleshooting mod_python troubleshooting] section, as most Apache-related issues are quite similar, plus discussion of potential [http://code.google.com/p/modwsgi/wiki/ApplicationIssues application issues] when using mod_wsgi. The wsgi page also has a [http://code.google.com/p/modwsgi/wiki/IntegrationWithTrac Integration With Trac] document.
    431409
     410
    432411----
    433 See also: TracGuide, TracInstall, [wiki:TracFastCgi FastCGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe]
     412See also:  TracGuide, TracInstall, [wiki:TracFastCgi FastCGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe]