[#9, #55] Added setup notes for the Python 2.7 and mod_wsgi upgrades.

setup/server/python2.7_mod_wsgi_installation.txt

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+Housekeeping
+------------
+ 1) Remove any old archives from:
+        /var/tmp/rsr/data_archives
+        /var/git/archives
+ 2) Remove any old backup databases through the mysql command-line tool:
+        rsrdb_xxx_timestamp
+ 3) Remove unused system packages:
+        sudo aptitude purge python-libxml2, pythonlibxslt1 and python-mysqldb
+ 4) List any broken packages then purge them if they're not needed:
+        sudo aptitude install
+ 5) Update any out of date system packages with aptitude
+        sudo aptitude update
+        sudo aptitude safe-upgrade
+        sudo aptitude install (to fix any missing dependencies, etc.)
+
+Pre-installation tidy-up
+------------------------
+ 1) Clear out the /var/virtualenvs dir: (the virtualenv will be rebuild with Python 2.7)
+        - remove any pip_install*.log files
+        - remove any virtualenvwrapper helper scripts (post*, pre*, hook.log, etc.)
+        - remove any old virtualenvs *except* the last release env
+ 2) Run pip freeze to see which system Python packages are installed.
+ 3) Remove any extraneous packages, esp. the following:
+        sudo pip uninstall supervisor meld3 mercurial
+        sudo pip uninstall virtualenvwrapper virtual
+    The only packges that should remain are: distribute, wsgiref and mod-python (though this will be uninstalled later)
+ 4) Ensure /usr/bin does not have any of the following binaries:
+        pip (this will have to be removed)
+        virtualenv
+        virtualenvwrapper.sh
+
+    Note: /usr/bin/pip-2.5 can still be used later if necessary else delete this as well
+
+Python 2.7 installation
+-----------------------
+ 1) Install Pythonbrew:
+        cd /some/temp/dir
+        export PYTHONBREW_ROOT=/usr/local/pythonbrew
+        curl -kLO http://xrl.us/pythonbrewinstall
+        chmod +x pythonbrewinstall
+        sudo ./pythonbrewinstall
+ 2) Create symlink for pythonbrew:
+        cd /usr/local/bin
+        sudo ln -s /usr/local/pythonbrew/bin/pythonbrew
+ 3) Disconnect and login again
+ 4) Install Python 2.7:
+        sudo PYTHONBREW_ROOT=/usr/local/pythonbrew pythonbrew install --no-setuptools --verbose 2.7.3 --configure=--enable-shared
+ 5) Enable and link Python 2.7:
+        sudo PYTHONBREW_ROOT=/usr/local/pythonbrew pythonbrew switch 2.7.3
+        cd /usr/local/bin
+        sudo ln -s /usr/local/pythonbrew/pythons/Python-2.7.3/bin/python
+        cd /lib
+        sudo ln -s /usr/local/pythonbrew/pythons/Python-2.7.3/lib/libpython2.7.so.1.0
+ 6) Disconnect and login again
+ 7) Install distribute and pip:
+        sudo bash
+        python --version (this should be 2.7.3 -- if not, check that you've linked the installed version in /usr/local/bin)
+        cd /some/temp/path
+        curl -kLO http://python-distribute.org/distribute_setup.py
+        sudo python distribute_setup.py
+        wget -nv --no-check-certificate https://raw.github.com/pypa/pip/master/contrib/get-pip.py
+        sudo python get-pip.py
+10) Create a symlink in /usr/local/bin for pip
+        sudo ln -s /usr/local/pythonbrew/pythons/Python-2.7.3/bin/pip /usr/local/bin/pip
+11) Use pip freeze to check the installation, which should list these packages:
+        distribute==0.6.27
+        wsgiref==0.1.2
+
+Reinstall the virtualenv tools
+------------------------------
+ 1) From your local machine, checkout the develop or release branch
+ 2) Run scripts/deployment/builders/rebuild_osx_dev_env.sh
+ 3) Update the system Python packges on the remote server:
+        workon rsr_develop
+        cd scripts/deployment/execution/steps
+        ./2_update_system_python_packages.py "preconfigured:test" [or "preconfigured:uat", etc.]
+ 4) Back on the host, pip freeze should list:
+        distribute==0.6.27
+        virtualenv==1.7.2
+        virtualenv-clone==0.2.4
+        virtualenvwrapper==3.5
+        wsgiref==0.1.2
+ 5) Create a symlink for virtualenv and virtualenvwrapper:
+        cd /usr/local/bin
+        sudo ln -s /usr/local/pythonbrew/pythons/Python-2.7.3/bin/virtualenv
+        sudo ln -s /usr/local/pythonbrew/pythons/Python-2.7.3/bin/virtualenvwrapper.sh
+ 6) Reboot the deployment host:
+        sudo reboot
+
+Install mod_wsgi
+----------------
+ 1) List the installed Apache packages with:
+        aptitude search apache | grep ^i
+    This should be:
+        apache2
+        apache2-mpm-prefork (since libapache2-mod-php5 depends on this package)
+        apache2-utils
+        apache2.2-common
+        libapache2-mod-php5
+    Install or replace any missing/incorrect modules
+ 2) Install Apache packages for mod_wsgi compilation:
+        sudo aptitude install apache2-prefork-dev
+ 3) Uninstall the mod_python package if necessary: (since we're replacing this with mod_wsgi)
+        sudo aptitude purge libapache2-mod-python
+ 4) Install mod_wsgi:
+        cd /some/temp/dir
+        wget http://modwsgi.googlecode.com/files/mod_wsgi-3.3.tar.gz
+        tar -xvf mod_wsgi-3.3.tar.gz
+        cd mod_wsgi-3.3
+        ./configure --with-python=/usr/local/bin/python --with-apxs=/usr/bin/apxs2
+        make
+        sudo make install
+ 5) Create a mod_wsgi loader file for Apache:
+        cd /etc/apache2/mods-available
+        sudo vi mod_wsgi.load
+    with the following contents:
+
+LoadModule wsgi_module /usr/lib/apache2/modules/mod_wsgi.so
+
+ 6) Update the Apache config files as follows: (adjust any paths as necessary)
+    a) create copies of the /etc/apache2/sites-available files in /usr/local/etc/akvo/apache2
+    b) edit the copied files in /usr/local/etc/akvo/apache2 only
+    c) add the following directives to the top of the file, above any VirtualHost sections:
+
+WSGIScriptAlias / /var/git/current/akvo/handler.py
+WSGIPythonPath /var/git/current:/var/virtualenvs/current/lib/python2.7/site-packages
+
+    d) withing the VirtualHost section and below the static content Directory directives, add the following:
+
+<Directory /var/git/current/akvo>
+    <Files handler.py>
+        Order deny,allow
+        Allow from all
+    </Files>
+</Directory>
+
+    e) remove any obsolete Location sections for the old akvo_modpython handler
+    f) ensure the access log is configured as follows:
+
+CustomLog /var/log/apache2/access.log combined env=!forwarded
+CustomLog /var/log/apache2/access.log proxy env=forwarded
+
+    g) create symlinks for the new config files
+        cd /etc/apache2/sites-available
+        sudo rm default
+        sudo rm akvotest.org.conf [or variant]
+        sudo ln -s /usr/local/etc/akvo/apache2/default
+        sudo ln -s /usr/local/etc/akvo/apache2/akvotest.org.conf
+
+ 7) Enable the mod_wsgi module and restart Apache:
+        sudo a2enmod mod_wsgi
+        sudo /etc/init.d/apache2 force-reload