Changes between Initial Version and Version 1 of TracDev/AlternativeFrontends

Timestamp:

Feb 22, 2010, 4:43:14 AM (14 years ago)

Author:

ryano@…

Comment:

Content moved from TracDev/DevelopmentEnvironmentSetup.

TracDev/AlternativeFrontends

@@ +1 @@
+= Alternative frontends =
+
+== Alternative frontend: mod_python ==
+
+Virtualenv can also be used with Apache and mod_python, but as mod_python will be a system install it will not be aware of the virtualenv without some configuration. For development this is useful as one Apache can serve various development versions in a more permanent way. This method will use the system Python, but will add the libraries from the virtualenv.
+
+'''Step 1:''' Make a new frontend script that for instance can be stored in the virtualenv 'bin' directory.
+
+{{{
+#!python
+#myvirtualtrac.py
+
+import os
+import site
+site.addsitedir('/path/to/my/virtualenv/lib/python2.4/site-packages')
+
+from trac.web.modpython_frontend import handler
+}}}
+
+'''Step 2:''' Update Apache config to use this script - add or update options according to the default mod_python setup like for instance found in TracModPython.
+
+{{{
+# Extend the path so Apache will find your script on path
+PythonPath "['/path/to/my/virtualenv/bin'] + sys.path"
+
+# Make mod_python use new frontend instead of trac.web.modpython_frontend
+PythonHandler myvirtualtrac
+}}}
+
+== Alternative frontend: mod_wsgi ==
+
+Using Apache, mod_wsgi is a very good alternative to mod_python. Setting this up follows the same pattern, but for development escpecially there is one major advantage: It can quite easily be set up to auto-reload on code changes.
+
+'''Step 1:''' Update a default TracModWsgi setup to make a deamonised process, and as of mod_wsgi 2.0 (this setup depends on >= 2.0) there is built-in support for custom paths and similar. Example of a full `VirtualHost` configuration:
+
+{{{
+<VirtualHost *:80>
+    ServerName virtualtrac.local
+
+    # Update user and group to be whatever on your system is intended to run the deamon
+    # Update the paths to point to virtualenv site-packages (for trac+++) and bin (for script)
+    WSGIDaemonProcess virtualtrac user=www group=www threads=25 python-path=/path/to/my/virtualenv/lib/python2.4/site-packages:/path/to/my/virtualenv/bin
+
+    WSGIScriptAlias / /path/to/my/virtualenv/bin/virtualtrac.wsgi
+
+    <Location />
+      WSGIReloadMechanism Process
+      WSGIProcessGroup virtualtrac
+      WSGIApplicationGroup %{SERVER}
+      Order deny,allow
+      Allow from all
+    </Location>
+
+    # Authentication
+    <LocationMatch (/[^/.]+/login)>
+      # Note: Change settings with regards to auth method, paths and domain
+      AuthType Digest
+      AuthName "virtualtrac"
+      AuthDigestDomain /trac http://virtualtrac.local
+      AuthDigestProvider file
+      AuthUserFile /path/to/access.htdigest
+      Require valid-user
+    </LocationMatch>
+
+</VirtualHost>
+}}}
+
+'''Step 2:''' Go to http://code.google.com/p/modwsgi/wiki/ReloadingSourceCode and save the long Python script that follows the text 'Example code for such an automatic restart mechanism...'. Save it as `/path/to/my/virtualenv/bin/monitor.py` 
+
+'''Step 3:''' A basic WSGI frontend script, save as `/path/to/my/virtualenv/bin/virtualtrac.wsgi`
+
+{{{
+#!python
+
+import sys
+sys.stdout = sys.stderr
+
+import os
+os.environ['TRAC_ENV_DIR'] = "/path/to/trac/project"
+# or, alternatively for multiple projects
+#os.environ['TRAC_ENV_PARENT_DIR'] = "/parent/path/to/many/projects"
+os.environ['PYTHON_EGG_CACHE'] = '/path/to/a/temp/to/cache/eggs'
+
+import trac.web.main
+
+import monitor
+monitor.start(interval=1.0)
+# Additionally monitor easy-install.pth to restart whenever installs are done
+monitor.track('/path/to/my/virtualenv/lib/python2.4/site-packages/easy-install.pth')
+
+application = trac.web.main.dispatch_request
+}}}