Getting Up and Running Locally With Docker
==========================================

.. index:: Docker

The steps below will get you up and running with a local development environment.
All of these commands assume you are in the root of your generated project.

Prerequisites
-------------

You'll need at least Docker 1.10.

If you don't already have it installed, follow the instructions for your OS:

 - On Mac OS X, you'll need `Docker for Mac`_
 - On Windows, you'll need `Docker for Windows`_
 - On Linux, you'll need `docker-engine`_

.. _`Docker for Mac`: https://docs.docker.com/engine/installation/mac/
.. _`Docker for Windows`: https://docs.docker.com/engine/installation/windows/
.. _`docker-engine`: https://docs.docker.com/engine/installation/

Attention Windows users
-----------------------

Currently PostgreSQL (``psycopg2`` python package) is not installed inside Docker containers for Windows users, while it is required by the generated Django project. To fix this, add ``psycopg2`` to the list of requirements inside ``requirements/base.txt``::

    # Python-PostgreSQL Database Adapter
    psycopg2==2.6.2

Doing this will prevent the project from being installed in an Windows-only environment (thus without usage of Docker). If you want to use this project without Docker, make sure to remove ``psycopg2`` from the requirements again.

Build the Stack
---------------

This can take a while, especially the first time you run this particular command
on your development system::

    $ docker-compose -f local.yml build

If you want to build the production environment you use ``production.yml`` as -f argument (``docker-compose.yml`` or ``docker-compose.yaml`` are the defaults).

Boot the System
---------------

This brings up both Django and PostgreSQL.

The first time it is run it might take a while to get started, but subsequent
runs will occur quickly.

Open a terminal at the project root and run the following for local development::

    $ docker-compose -f local.yml up

You can also set the environment variable ``COMPOSE_FILE`` pointing to ``local.yml`` like this::

    $ export COMPOSE_FILE=local.yml

And then run::

    $ docker-compose up

Running management commands
~~~~~~~~~~~~~~~~~~~~~~~~~~~

As with any shell command that we wish to run in our container, this is done
using the ``docker-compose -f local.yml run`` command.

To migrate your app and to create a superuser, run::

    $ docker-compose -f local.yml run django python manage.py migrate
    $ docker-compose -f local.yml run django python manage.py createsuperuser

Here we specify the ``django`` container as the location to run our management commands.

Add your Docker development server IP
-------------------------------------

When ``DEBUG`` is set to `True`, the host is validated against ``['localhost', '127.0.0.1', '[::1]']``. This is adequate when running a ``virtualenv``. For Docker, in the ``config.settings.local``, add your host development server IP to ``INTERNAL_IPS`` or ``ALLOWED_HOSTS`` if the variable exists.

Production Mode
~~~~~~~~~~~~~~~

Instead of using `local.yml`, you would use `production.yml`.

Other Useful Tips
-----------------

Make a machine the active unit
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This tells our computer that all future commands are specifically for the dev1 machine.
Using the ``eval`` command we can switch machines as needed.

::

    $ eval "$(docker-machine env dev1)"

Detached Mode
~~~~~~~~~~~~~

If you want to run the stack in detached mode (in the background), use the ``-d`` argument:

::

    $ docker-compose -f local.yml up -d

Debugging
~~~~~~~~~~~~~

ipdb
"""""

If you are using the following within your code to debug:

::

    import ipdb; ipdb.set_trace()

Then you may need to run the following for it to work as desired:

::

    $ docker-compose -f local.yml run --service-ports django


django-debug-toolbar
""""""""""""""""""""

In order for django-debug-toolbar to work with docker you need to add your docker-machine ip address to ``INTERNAL_IPS`` in ``local.py``


.. May be a better place to put this, as it is not Docker specific.

You may need to add the following to your css in order for the django-debug-toolbar to be visible (this applies whether Docker is being used or not):

.. code-block:: css

    /* Override Bootstrap 4 styling on Django Debug Toolbar */
    #djDebug[hidden], #djDebug [hidden] {
        display: block !important;
    }

    #djDebug [hidden][style='display: none;'] {
        display: none !important;
    }


Using the Mailhog Docker Container
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In development you can (optionally) use MailHog_ for email testing. If you selected `use_docker`, MailHog is added as a Docker container. To use MailHog:

1. Make sure, that ``mailhog`` docker container is up and running
2. Open your browser and go to ``http://127.0.0.1:8025``

.. _Mailhog: https://github.com/mailhog/MailHog/