View source for Django-Installation

(See also: [[Artenquiz documentation]])

== Help Commands ==

<source lang="bash">
django-admin.py --version # 1.6.5
</source>

== Install automatically ==

===Under Debian 6, Squeeze===

<source lang="bash">
#default version is 1.2:
sudo apt-get update # get updated package data
apt-cache showpkg python-django # check version
sudo apt-get install python-django python-django-registration python-mysqldb
# Instead, it is possible to install 1.3.1 from squeeze backport - WE DID THIS:
sudo apt-get remove python-django
sudo apt-get -t squeeze-backports install python-django  python-django-registration
# Result was: Setting up python-django (1.3.1-2~bpo60+1)
</source>

Advantage of debian repository installation is that apt-get update will inject any necessary security updates.

'''NOTE:''' python-django-registration is NOT in a current version, but in an older one than we used before. Debian has only 0.7.x, we had used  0.8alpha. Thus: sudo apt-get remove python-django-registration and installed manually!

=== Use Python pip ===

Alternative 1: Use alternative python package installer (instead of easy_install):
<syntaxhighlight lang="bash">
sudo apt-get update # get updated package data
sudo apt-get install python-pip
# first install or install a specific version
pip install django==1.4.2
# upgrade: there is a upgrade option (pip install --upgrade) and may work, or deinstall and reinstall it
pip uninstall django
pip install django==1.5
</syntaxhighlight>

Alterantive 2: use [https://pip.pypa.io/en/latest/installing.html#install-pip get-pip.py (documentation)]
<syntaxhighlight lang="bash">
# go to home directory and create a temp folder and go into it
cd ~ && mkdir temp && cd ./temp
wget https://bootstrap.pypa.io/get-pip.py
sudo python get-pip.py
</syntaxhighlight>

=== Useful tools ===
 pip install [https://pypi.python.org/pypi/django-debug-toolbar django-debug-toolbar]
 pip install [https://pypi.python.org/pypi/django-annoying django-annoying]

== Manually == 
=== Django ===
[[File:Django_logo.svg | 100px | Django framework to build websites | right | link = http://www.djangoproject.com/]]
[http://www.djangoproject.com/ Django] is a high-level [[w:Python|Python]] Web framework that encourages rapid development and clean, pragmatic design.

Version in lenny is 1.0, which is too old. 
<syntaxhighlight lang="bash">
# Download 
mkdir ~/temp
cd ~/temp
wget http://www.djangoproject.com/download/1.2.5/tarball/
# extract
tar xzvf Django-1.2.5.tar.gz
# install (see http://docs.djangoproject.com/en/1.2/topics/install/#installing-official-release)
cd ./Django-1.2.5
sudo python setup.py install --prefix /usr/local

# Install mod_wsgi for Apache (it is enabled automatically):
apt-get install libapache2-mod-wsgi
</syntaxhighlight>

To use this version with the application “artenquiz”, add an apache virtual host (see /etc/apache2/sites-enabled/artenquiz).

=== Access to a MSSQL Server ===
==== Installations ====

Following the tutorial [http://logrit.com/weblog/2012/07/16/accessing-sql-server-mssql-database-django/ Accessing a SQL Server (MSSQL) database from Django (2013)]:
<syntaxhighlight lang="bash">
sudo apt-get install freetds-common freetds-bin tdsodbc
# subversion, unixodbc is already installed
sudo apt-get build-dep pyodbc
# undo build-dep
#   sudo aptitude markauto $(apt-cache showsrc build-dep | grep Build-Depends | perl -p -e 's/(?:[[(].+?[])]|Build-Depends:|,||)//g')
#   sudo apt-get autoremove
cd ~ && mkdir temp && cd ./temp
svn checkout http://django-pyodbc.googlecode.com/svn/trunk/ django-pyodbc-read-only
cd django-pyodbc-read-only
sudo python setup.py build install
# needs pip (python package installer)
sudo pip install pyodbc # does not work so follow the instructions given in the command line
sudo pip install --allow-external pyodbc pyodbc # does not work so follow the instructions given in the command line
sudo pip install --allow-unverified pyodbc pyodbc # OK
</syntaxhighlight>

==== BUG Fix ==== 
Correct a BUG in operations.py around line 10
<syntaxhighlight lang="bash">
PYTHON_SITEPACKAGES_DIR=`python -c "from distutils.sysconfig import get_python_lib; print get_python_lib()"`
sudo vi "${PYTHON_SITEPACKAGES_DIR}/sql_server/pyodbc/operations.py"
</syntaxhighlight>
{|
|-
! old with BUG !! BUG corrected
|-
|
<syntaxhighlight lang="python" line="true" start="7">
class DatabaseOperations(BaseDatabaseOperations):
    compiler_module = "sql_server.pyodbc.compiler"
    def __init__(self, connection):
        super(DatabaseOperations, self).__init__()
        self.connection = connection
        self._ss_ver = None
</syntaxhighlight>
|
<syntaxhighlight lang="python" highlight="4" line="true" start="7">
class DatabaseOperations(BaseDatabaseOperations):
    compiler_module = "sql_server.pyodbc.compiler"
    def __init__(self, connection):
        super(DatabaseOperations, self).__init__(connection)
        self.connection = connection
        self._ss_ver = None
</syntaxhighlight>
|}

==== Configurations ====
And the configurations:
{| class="vertical-align-top"
|-
! edit command
! content of configuration
|-
|
<syntaxhighlight lang="bash">
sudo vi /etc/freetds/freetds.conf
</syntaxhighlight>
|
<syntaxhighlight lang="text">
[MSSQL-PYTHON]
host = host.of.sqlserver.de
port = 1234
tds version = 8.0 
</syntaxhighlight>
|-
|
<syntaxhighlight lang="bash">
sudo vi /etc/odbc.ini
</syntaxhighlight>
|
Make sure before configuring, that the path for “Driver” is correct you find it by searching files in <code>/usr/</code>
<syntaxhighlight lang="bash">
find /usr/ -name "*libtdsodbc*" -type f
</syntaxhighlight>

<syntaxhighlight lang="text">
[ODBC Data Sources]
ODBCNAME = Microsoft SQL Server
[MSSQL-PYTHON]
Driver = /usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so
Description = Connect to xy-database by MSSQL-PYTHON driver
Trace = No
Database = xy-database
Server = host.of.sqlserver.de
Port = 1234
</syntaxhighlight>
|}

After creating andjango project by 
<syntaxhighlight lang="bash">
cd /myfolder/
django-admin startproject django_mssql_project
# tree django_mssql_project
# django_mssql_project/
# ├── django_mssql_project
# │   ├── __init__.py
# │   ├── settings.py
# │   ├── urls.py
# │   └── wsgi.py
# ├── __init__.py
# ├── manage.py
# ├── settings.py
# └── urls.py
</syntaxhighlight>
Configure the database connection in django_mssql_project/settings.py
<syntaxhighlight lang="text">
DATABASES = {
    'default': {
        'ENGINE': 'sql_server.pyodbc', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': '<Database name>',                      # Or path to database file if using sqlite3.
        'USER': '<Database user>',                      # Not used with sqlite3.
        'PASSWORD': '<Database password>',                  # Not used with sqlite3.
        'HOST': 'MSSQL-PYTHON',                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': '1433',                      # Set to empty string for default. Not used with sqlite3.
        'OPTIONS': {
                'host_is_server': False,
                'dsn': 'MSSQL-PYTHON',
        },
    }
}
DATABASE_NAME = '<Database name>'
DATABASE_HOST = 'MSSQL-PYTHON'
DATABASE_PORT = '1433'
DATABASE_USER = '<Database user>'
DATABASE_PASSWORD = '<Database password>'
DATABASE_OPTIONS = {
        'host_is_server': False,
        'dsn': 'MSSQL-PYTHON',
}
</syntaxhighlight>

==== Tests ====
Test the access by displaying all tables:
{|
|-
|<syntaxhighlight lang="bash">
isql -v MSSQL-PYTHON <Username> <Password>
</syntaxhighlight>
|<syntaxhighlight lang="sql">
SELECT * FROM INFORMATION_SCHEMA.TABLES;
</syntaxhighlight>
|}

Or use tha Django management program to check if it is working, e.g
<syntaxhighlight lang="bash">
python ./manage
python ./manage inspectdb
</syntaxhighlight>

== Install/Upgrade by script ==

Using the following bash script you can upgrade django to a certain version, here 1.3. It tries to download that version and optionally delete the old one first. For more details see also http://docs.djangoproject.com/en/dev/topics/install/#how-to-install-django
<blockquote>
<source lang="bash">
#!/bin/bash
# define a version
djversion=1.3
#get directories
#SITEPACKAGESDIRLOCAL=/usr/local/lib/python2.5/site-packages
SITEPACKAGESDIRLOCAL=`python -c "from distutils.sysconfig import get_python_lib; print get_python_lib(0, 0, '/usr/local')"`
SITEPACKAGESDIR=`python -c "from distutils.sysconfig import get_python_lib; print get_python_lib()"`

echo "Remove older django first?"
select yn in "Yes" "No"; do
    case $yn in
        Yes ) echo "Remove django..."; 
          cd $SITEPACKAGESDIRLOCAL
          sudo rm -r Django*
          sudo rm -r django*
          sudo rm -i /usr/local/bin/django-admin.py
          sudo rm -i $SITEPACKAGESDIR/django.pth
        break;;
        No ) break;;
    esac
done

echo "Download django $djversion and install?"
select yn in "Yes" "No"; do
    case $yn in
        Yes ) 
          echo "Download django..."; 
          # download
            wget "http://www.djangoproject.com/download/$djversion/tarball/" --output-document=Django-${djversion}.tar.gz
            if [ -a Django-${djversion}.tar.gz ]; then
              # extract
              tar xzf Django-${djversion}.tar.gz
                cd Django-${djversion}
              echo "Django extracted to ./Django-${djversion}"; 
              echo "Install to ${SITEPACKAGESDIRLOCAL}..."; 
              # install
              sudo python setup.py install --prefix /usr/local
              # some information
              echo "**************************************"
              echo "Files are in:"
              echo ${SITEPACKAGESDIRLOCAL}
              echo ${SITEPACKAGESDIR}
              echo "/usr/local/bin/django-admin.py"
              echo "**************************************"
            else
              echo "Could not download Django-${djversion}.tar.gz. Stop."
              exit
            fi # end Django-${djversion}.tar.gz
        break;;
        No ) echo "Exit."; exit;;
    esac
done
</source>
</blockquote>

== Reloading Source Code ==

The mod_wsgi is an extra layer additionally to the apache. Usually when there is any code change on py-files it will reload. However sometimes it does not. Further reading: http://code.google.com/p/modwsgi/wiki/ReloadingSourceCode

== Miscellaneous ==

'''Management tasks'''
<blockquote>
<source lang="bash">
djangoPath=/to/my/django/application/
cd $djangoPath
# get help infos
  python manage.py help
  python manage.py help createsuperuser
# create a superuser
  python manage.py createsuperuser
# show django’s default database model descriptions based on the database in settings.py
  python manage.py inspectdb
# run developement server on http://127.0.0.1:8000/
  python manage.py runserver
# get python shell for django
  python manage.py shell

# start a project
  django-admin.py help
  django-admin.py startproject mysite 
# create an application
  django-admin.py help
  django-admin.py startapp myapp # in the current directory
</source>
</blockquote>

'''Directory architecture'''
<div style="margin-left:40px;">
 django-project-root
 ├─ apache/
 │  └─ django.wsgi {{Comment gray| ''mod_wsgi interface between webserver and Python applications''}}
 │
 ├─ yourapp/
 │  ├─ models.py {{Comment gray| ''model definitions''}}
 │  ├─ admin.py  {{Comment gray| ''admin GUI settings''}}
 │  └─ views.py  {{Comment gray| ''view layer definitions''}}
 │
 ├─ locale/ {{Comment gray| ''localized application messages for internationalisation''}}
 │  ├─ de/LC_MESSAGES/
 │  │     ├─ django.po  {{Comment gray| ''string dictionary for German. Created with:'' django-admin.py makemessages -l de}}
 │  │     └─ django.mo  {{Comment gray| ''machine readable output. Created with:'' django-admin.py compilemessages}}
 │  ├─ en/LC_MESSAGES/
 │  │     ├─ …
 │  │     └─ …
 │  └─  …/LC_MESSAGES/
 │
 ├─ templates/ {{Comment gray| ''organizing HTML templates here''}}
 │  ├─ base.html
 │  └─ quiz.html
 │
 ├─ manage.py   {{Comment gray| ''management tasks''}}
 ├─ settings.py {{Comment gray| ''the program’s settings''}}
 └─ urls.py     {{Comment gray| ''settings of url patterns''}}
</div><!-- ┌ ┬ ┐ ├ ┼ ┤ └ ┴ ┘ │ ─ -->

'''Install [https://bitbucket.org/ubernostrum/django-registration/src/tip/docs/ django-registration]'''

Version 0.7
<blockquote>
<source lang="bash">
sudo easy_install django-registration
# uninstall
sudo easy_install -m django-registration
cd /usr/lib/python2.5/site-packages/
sudo rm django_registration-0.7-py2.5.egg
</source>
</blockquote>

Version 0.8 alpha will install into <code>/usr/local/lib/python2.5/site-packages/</code> using <code>--prefix /usr/local</code>
<blockquote>
<source lang="bash">
wget https://bitbucket.org/ubernostrum/django-registration/downloads/django-registration-0.8-alpha-1.tar.gz
tar zxvf django-registration-0.8-*.tar.gz
cd django-registration-0.8-alpha/
sudo python setup.py install --prefix /usr/local
</source>
</blockquote>

== Admin UI ==

If you have created a super user account by:
<source lang="bash">
  djangoPath=/to/my/django/application/
  cd $djangoPath
  # get help infos
  #  python manage.py help createsuperuser
  # create a superuser
  python manage.py createsuperuser
</source>
You have access now to http://your-website/admin. Which data base models are shown, is set in 
<div style="margin-left:40px;">
 django-project-root
 └─ yourapp/
    └─ admin.py  {{Comment gray| ''admin GUI settings''}}
</div>

== Apache Configuration ==

* create alias also for /admin UI
<syntaxhighlight lang="bash">
sudo vi /etc/apache2/sites-available/mysite
</syntaxhighlight>
<syntaxhighlight lang="apache">
# apache config mysite alias
        WSGIScriptAlias / /path/to/django/app/django-wsgi-handler.wsgi
        Alias /static/admin/ /usr/share/pyshared/django/contrib/admin/static/admin/
        Alias /static/ /path/to/django/app/static/
        Alias /favicon.ico /path/to/django/app/static/img/favicon.ico
</syntaxhighlight>

== Additional useful software ==

* python-docutils: enables the automatic generation of python code documentation that appears then in the Django admin user web-interface. A great help for administrators or programmers.

== Problem Solving ==

Error:
 ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb

Solution: Multiple. In general the MySQL database connection is lost see also https://stackoverflow.com/questions/29631430/error-loading-mysqldb-module-in-python-django#34976643
 aptitude search '~i python-mysqldb' # search for installed package python-mysqldb
If it is not there and if <code>pip list</code> ''does not'' list package <code>MySQL-python</code> then the following install might resolve this in installing package <code>python-mysqldb</code>:
 sudo apt-get install python-mysqldb
 
[[Category: Django]]
[[Category: Trouble shooting]]