Manage bower components and node packages using Django

Many Django applications require some JavaScript packages, which usually are not available on PyPI and thus can't be installed through pip. A common solution to this problem is, to copy these JavaScript packages into the Django application. This however is a bad solution, since then these packages have to be revisioned twice. By adding the file(s) bower.json and/or package.json to each Django application, this problem can be solved in a portable and elegant manner.

With django-nodebow manage your JavaScript dependencies from all of your Django projects centrally for the required bower components and/or node packages, simply through:

./manage.py bower install
# and/or
./manage.py npm install

The nice feature of django-nodebow is, that each Django application can specify which external packages it requires itself, without adding these to its own Git repository.

Installation

Install NodeJS.

Into your global NodeJS packages folder, install bower:

sudo npm install -g bower inquirer

Into your Python virtualenv:

pip install django-nodebow
pip install PyExecJS

Configuration

In settings.py:

INSTALLED_APPS = (
    ...
    'nodebow',
    ...
)

STATICFILES_FINDERS = (
    ...
    'nodebow.finders.BowerComponentsFinder',
    ...
)

Optional settings

By default, the folders bower_components and/or node_packages are placed into the STATIC_ROOT of your Django project. Therefore make sure, this directory is available, even during development.

NPM searches for its global node modules in a folder, which can be set using the environment variable NODE_PATH. This can be overridden by a settings variable with the same name. If both are unset, this location is determined by executing npm root -g in the shell.

Usage

To install all the bower components which are required for your Django project, simply invoke:

./manage.py bower install

This will iterate over all applications defined in your INSTALLED_APPS settings, and look for a file named bower.json. If such a file was found, the list of dependencies is resolved and the corresponding packages are installed into the folder bower_components of the local Django project.

Say, one of the processed bower.json files contains an entry

  ...
  "dependencies": {
    ...
    "jquery": "~2.0.3",
    ...
  }

then, when accessing the main file, use

	{% load static %}
	...
	<script src="{% static 'jquery/jquery.js' %}" type="text/javascript"></script>
	...

in any of your Django templates.

As of version 0.0.1 ./manage npm install, currently does not work.

Difference between Bower and NPM

npm is most commonly used for managing Node.js modules, which run exclusively on the server-side.

Bower is created solely for the front-end and is optimized with that in mind. The biggest difference is that npm does nested dependency tree (size heavy) while Bower requires a flat dependency tree. This puts the burden of dependency resolution on the user.

A nested dependency tree means that your dependencies can have its own dependencies which can have their own, and so on. This is really great on the server where you don't have to care much about space and latency. It lets you not have to care about dependency conflicts as all your dependencies use e.g. their own version of Underscore. This obviously doesn't work that well on the front-end. Imagine a site having to download three copies of jQuery.