Warnings and errors after trying to install Flask 0.9

Question

I'm trying ot install Flask, but I'm betting all these warnings and errors:

alex@alex-K43U:~/flask$ pip install Flask
Downloading/unpacking Flask
  Downloading Flask-0.9.tar.gz (481Kb): 481Kb downloaded
  Running setup.py egg_info for package Flask

    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'docs'
    warning: no previously-included files matching '*.pyo' found under directory 'docs'
    warning: no previously-included files matching '*.pyc' found under directory 'tests'
    warning: no previously-included files matching '*.pyo' found under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'examples'
    warning: no previously-included files matching '*.pyo' found under directory 'examples'
    no previously-included directories found matching 'docs/_build'
    no previously-included directories found matching 'docs/_themes/.git'
Downloading/unpacking Werkzeug>=0.7 (from Flask)
  Downloading Werkzeug-0.8.3.tar.gz (1.1Mb): 1.1Mb downloaded
  Running setup.py egg_info for package Werkzeug

    warning: no files found matching '*' under directory 'werkzeug/debug/templates'
    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'docs'
    warning: no previously-included files matching '*.pyo' found under directory 'docs'
    warning: no previously-included files matching '*.pyc' found under directory 'tests'
    warning: no previously-included files matching '*.pyo' found under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'examples'
    warning: no previously-included files matching '*.pyo' found under directory 'examples'
    no previously-included directories found matching 'docs/_build'
Downloading/unpacking Jinja2>=2.4 (from Flask)
  Downloading Jinja2-2.6.tar.gz (389Kb): 389Kb downloaded
  Running setup.py egg_info for package Jinja2

    warning: no previously-included files matching '*' found under directory 'docs/_build'
    warning: no previously-included files matching '*.pyc' found under directory 'jinja2'
    warning: no previously-included files matching '*.pyc' found under directory 'docs'
    warning: no previously-included files matching '*.pyo' found under directory 'jinja2'
    warning: no previously-included files matching '*.pyo' found under directory 'docs'
Installing collected packages: Flask, Werkzeug, Jinja2
  Running setup.py install for Flask

    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'docs'
    warning: no previously-included files matching '*.pyo' found under directory 'docs'
    warning: no previously-included files matching '*.pyc' found under directory 'tests'
    warning: no previously-included files matching '*.pyo' found under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory 'examples'
    warning: no previously-included files matching '*.pyo' found under directory 'examples'
    no previously-included directories found matching 'docs/_build'
    no previously-included directories found matching 'docs/_themes/.git'
    error: could not create '/usr/local/lib/python2.7/dist-packages/flask': Permission denied
    Complete output from command /usr/bin/python -c "import setuptools;__file__='/home/alex/flask/build/Flask/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /tmp/pip-KD7NsY-record/install-record.txt:
    running install

running build

(a lot of creating and building)

error: could not create '/usr/local/lib/python2.7/dist-packages/flask': Permission denied

Any suggestions to solve this problem?

I'm using ubuntu 11.10.

Answer 1

The warnings you can safely ignore; however this error:

error: could not create '/usr/local/lib/python2.7/dist-packages/flask': Permission denied

Tells me that you are trying to install this in to your global system Python. Nothing wrong with that, but if you want to do that you need to run the command with elevated privileges (using sudo).

It is better to use a virtual environment so that you don't pollute the system-wide Python install.

Using a virtual environment:

$ virtualenv flask_env
$ source flask_env/bin/activate
(flask_env) $ pip install Flask

You should probably install the virtualenv binaries first with sudo apt-get install python-virtualenv

Answer 2

As for the warnings, they can sometimes be ignored. The only relevant line is the last one, which says the application does not have permission to create a directory in that folder.

Add sudo to your command to fix this.

sudo pip install Flask

As a general rule, you don't want to install packages system wide. In the Python world the norm is using virtual env to create a local environment, and install packages into each of these. You can find some more information on virtualenv here.