Script for updating requirements.txt using Kenneth Reitz's new better pip workflow: http://www.kennethreitz.org/essays/a-better-pip-workflow

update-requirements.bash

#!/bin/bash
set -efxu

cd "$(dirname "$0")/.."

if [ ! -f requirements-to-freeze.txt ]; then
    echo "No requirements to freeze file found!"
    exit 1
fi

rm -rf virtualenv
python -m virtualenv virtualenv -q

rm requirements.txt
virtualenv/bin/pip install -r requirements-to-freeze.txt --upgrade
virtualenv/bin/pip freeze > requirements.txt