Django runserver error (psycopg2)

Question

I'm trying to do this:

python3.3 manage.py runserver

In my Django project folder. I get this error message:

  File "/usr/local/lib/python3.3/site-packages/django/db/backends/postgresql_psycopg2/base.py", line 25, in <module>
    raise ImproperlyConfigured("Error loading psycopg2 module: %s" % e)
django.core.exceptions.ImproperlyConfigured: Error loading psycopg2 module: No module  named 'psycopg2'

My settings in settings.py are the following:

DATABASES = {
    'default': {
        'ENGINE':'django.db.backends.postgresql_psycopg2',
        'NAME': 'test_databas',
        'USER': 'postgre',
        'PASSWORD': 'mypassword',
        'HOST': 'localhost',
        'PORT': '5432',
    }
}

I have already downloaded psycopg2 with Python3.3. The file /usr/local/lib/python3.3/site-packages/django/db/backends/postgresql_psycopg2/base.py also exists. However, Python doesn't think I have a module named psycopg2. I have tried this:

$ python3.3
Python 3.3.3 (default, Feb  2 2014, 14:32:49) 
[GCC 4.6.3] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import psycopg2
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named 'psycopg2'
>>> 

I have also changed my sys.path as suggested here.

I'm new to this and would be very grateful for some help.

Solution 1

I check my local installation of psycopg2

apt-cache show python-psycopg2

Package: python-psycopg2

Priority: optional

Section: python

Installed-Size: 635

...

Source: psycopg2

Version: 2.4.5-1

Depends: python2.7, python (>= 2.7.1-0ubuntu2), python (<< 2.8), libc6 (>= 2.14), libpq5 (>= 8.3~)

So, python-psycopg2 installs you the version which is not compatible with python 3.x But also there is a a package named python3-psycopg2 When I check it, it looks like it is also Version: 2.4.5-1 but descriptive text tells it is compatible with python 3.2

apt-cache show python3-psycopg2

Package: python3-psycopg2

Priority: optional

Version: 2.4.5-1

Provides: python3.2-psycopg2

Depends: python3 (>= 3.2), python3 (<< 3.3), libc6 (>= 2.14), libpq5 (>= 8.3~)

Also, package sizes are different. Probably python3-psycopg2 is what you need, it was only mis-versioned on the documents.

Solution 2

I was facing this problem and solved following the process are given below:

Install pip3:

sudo apt-get install python3-pip

Install virtualenv:

sudo pip3 install virtualenv

Install posgresql dependency:

sudo apt-get install python3-dev libpq-dev

Configure virtualenv:

mkdir django
cd django
virtualenv -p /usr/bin/python3.4 venv
source venv/bin/activate

Install django:

pip3 install django

Install psycopg2:

pip3 install psycopg2

Comments

[Myone]

Yes I was using the default user. Thanks! I have already changed my path variable and that didn't help unfortunately. However I somehow managed to solve the problem myself using easy_install instead.

[FallenAngel]

That can not be the reason because error says it can not import related module. In your situation, Django will throw Database Connection based error, not ImportError

[Myone]

Thanks, now I see why my apt-get command didn't work. Apparently easy_install automatically installs the python3 version. Thanks!

[FallenAngel]

Probably easy_install installed the latest version, while linux package index contains 2 packages, one for 3.x and the other is for 2.x

[3manuek]

That's why I commented after about the installation process. I didn't say that the user name fix is the reason. Sorry the lack of detail.