Chimère upgrade

Author:Étienne Loks
date:2012-02-15
Copyright:CC-BY 3.0

This documents presents the upgrade of Chimère to version 1.2. This documentation is no longer relevant for version 2.

Get new version of dependencies

From version prior to 1.1 to 1.1

Upgrade Django to the 1.2 version. Install the Beautiful Soup library.

Get the new version

First of all get the new version of the code source.

Download archive from the download site

Versions are available at this address. Take care of getting the last version in the desired X.Y branch (for instance the last version for the 1.0 branch is version 1.0.2 as the time of writing of this document). Extract it to the desired destination path.:

su
wget http://www.peacefrogs.net/download/chimere -q -O -| html2text
(...)
[[   ]] chimere-1.0.0.tar.bz2     17-Nov-2010 16:51  53K
[[   ]] chimere-1.0.1.tar.bz2     17-Nov-2010 16:51  53K
[[   ]] chimere-1.0.2.tar.bz2     17-Nov-2010 16:51  53K
(...)

wget http://www.peacefrogs.net/download/chimere/chimere-1.0.2.tar.bz2
mv chimere-1.0.2.tar.bz2 /var/local/django
cd /var/local/django
tar xvjf chimere-1.0.2.tar.bz2
cd chimere-1.0.2

Get from the Git repository

Clone the Git repository, checkout the desired version and copy it to the desired destination path.:

git clone git://www.peacefrogs.net/git/chimere
cd chimere
git tag -l
(...)
v1.2.0
v1.2.1
git checkout v1.2.1
cd ..
mv chimere /var/local/dgango/chimere-1.0
cd /var/local/dgango/chimere-1.0

Copy files from your old installation

From your old installation at least copy “settings.py” and the content of “static/icons/” and “static/upload/” to the new installation. You have probably customised some styles and templates (for instance “styles.css”, “welcome.html” and “base_user.html”) don’t forget to copy them and eventualy adapt them (if you have old vanilla version of this file comparing with the new one provided is easier).

Adapt settings.py

The format of settings.py could have evolved, the easiest way to complete your settings.py is to compare your old settings.py.example and the new one provided.

Specific to upgrade from version 1.0 to version 1.1

Version 1.1 of Chimère uses Django 1.2 and with it the manner to define database has changed.

Old way to define your database is:

DATABASE_ENGINE = 'postgresql_psycopg2'
DATABASE_NAME = 'chimere'
DATABASE_USER = 'chimere-user'
DATABASE_PASSWORD = 'password'
DATABASE_HOST = 'localhost'
DATABASE_PORT = ''

The new one looks like:

DATABASES = {
    'default': {
    'NAME': 'ratatouille',
    'ENGINE': 'django.contrib.gis.db.backends.postgis',
    'HOST': 'localhost',
    'PORT': '5432',
    'USER': 'chimere-user',
    'PASSWORD': 'password',
    },
}

Be careful to adapt properly your settings.py

Run migration scripts

Migration scripts test your installation before making changes so you probably won’t have any lost but by precaution before running theses scripts don’t forget to backup your database. You can also make a copy of your current database into a new database and make the new installation to this new database.

The gdal binding for python is necessary to run the upgrade scripts (available in the python-gdal package in Debian).

If you run the migration scripts in a production environnement stop the old instance of Chimère before executing the migration script. Perhaps prepare the web server to point to the new installation before doing the database upgrade (cf. next paragraph).

In “settings.py” verify that “chimere.scripts” is in the INSTALLED_APPS.

After that in the chimere directory just execute the script:

python ./scripts/upgrade

Point to the new installation

Most of the job is done. You’ll just have to configure your web server to serve the new version.

For instance for Apache the directive is changed from:

PythonPath "['/var/local/django/chimere/'] + sys.path"

To:

PythonPath "['/var/local/django/chimere-1.0.2/'] + sys.path"

Restart your web server and apart from web browser cache issues this should work.

Force the upgrade of visitor’s web browser cache

If major changes in the javascript has be done between version, many of your users could experience problems. There are many tricks to force the refresh of their cache. One of them is to change the location of statics files. To do that edit your settings.py and change:

MEDIA_ROOT = ROOT_PATH + 'static/'
MEDIA_URL = '/' + EXTRA_URL + 'static/'

To:

MEDIA_ROOT = ROOT_PATH + 'static/v1.0.2/'
MEDIA_URL = '/' + EXTRA_URL + 'static/v1.0.2/'

Then in the static directory:

ln -s `pwd` v1.0.2

Restart the web server to apply changes.