Part 8: Finishing

Adding a License

FreedomBox is licensed under the GNU Affero General Public License Version 3 or later. FreedomBox apps, which run as modules under FreedomBox Service (Plinth), also need to be under the same license or under a compatible license. The license of our app needs to clear for our app to be accepted by users and other developers. Let us add license headers to our application.

# SPDX-License-Identifier: AGPL-3.0-or-later

The above header needs to be present in every file of the application. It is suitable for Python files. However, in template files, we need to modify it slightly.

{% extends "base.html" %}
{% comment %}
# SPDX-License-Identifier: AGPL-3.0-or-later
{% endcomment %}

Coding standards

For readability and easy collaboration it is important to follow common coding standards. FreedomBox uses the Python coding standards and uses the pylint and flake8 tools to check if the there are any violations. yapf and isort tools are used to automatically format the code to ensure that all developers produce similarly formatted code. Run these tools on our application and fix any errors and warnings. Better yet, integrate these tools into your favorite IDE for on-the-fly checking.

For the most part, the code we have written so far, is already compliant with the coding standards. This includes variable/method naming, indentation, document strings, comments, etc. One thing we have to add are the module documentation strings. Let us add those. In __init__.py add the top:

"""
FreedomBox app to configure Transmission.
"""

Contributing code to FreedomBox

The HACKING.md and CONTRIBUTING.md files in the FredomBox source code have tips on how to contribute code to the project. Be sure to read them if you are submitting your app for including on the project.

Here is HACKING.md:

# Hacking

This document provides reference information for FreedomBox **contribution** hacking **procedures**:
1. [Picking a task to work on](#picking-a-task-to-work-on)
1. [Setting up and using development environments](#development-environments-setting-up-and-their-usage)
1. [Contributing translations + how to make/keep FreedomBox international](#makingkeeping-freedombox-international)
1. [Testing](#testing)
1. [Documentation](#documentation)
1. [Submitting your changes](#submitting-your-changes)
1. [Other related stuff](#miscelanea)

It doesn't cover arquitecture, design choices, or other product internals.

## Picking a task to work on

You can report bugs on FreedomBox Service's (Plinth's) [issue
tracker](https://salsa.debian.org/freedombox-team/freedombox/issues).
Newcomers will find easy, self-contained tasks tagged as "beginner".

Source code for FreedomBox Service is available from
[salsa.debian.org](https://salsa.debian.org/freedombox-team/freedombox).



## Development environments: setting up and their usage

### Requirements for Development OS

FreedomBox is built as part of Debian GNU/Linux. However, you don't need to
install Debian to do development for FreedomBox. FreedomBox development is
typically done with a container or a Virtual Machine.

* For running a container, you need systemd containers, Git, Python3 and a
sudo-enabled user. This approach is recommended.
* For running a VM, you can work on any operating system that can install latest
versions of Git, Vagrant and VirtualBox.

In addition:

- To run code quality checks you need flake8 and yapf. These may be installed
  inside the container with Python3 and pip but installing them on host leads to
  smoother development experience.
- To update translation strings on the host machine, you need Django and gettext
  to be installed on host machine. These can be installed with Python3 and pip.
- You need Mumble voice chat software to participate in bi-weekly live
  development discussions.

### Using Containers

The `./container` script shipped with FreedomBox source code can manage the
development environment inside a systemd-nspawn container.

1.  Checkout FreedomBox Service (Plinth) source code using Git:

    ```bash
    host$ git clone https://salsa.debian.org/freedombox-team/freedombox.git
    host$ cd freedombox
    ```

2.  Work in a specific branch:
    ```bash
    host$ git branch YOUR-FEATURE-BRANCH
    host$ git checkout YOUR-FEATURE-BRANCH
    ```

3.  To download, setup, run, and configure a container for FreedomBox
    development, simply execute in your FreedomBox Service (Plinth) development
    folder: (This step requires at least 16GB of free disk space)

    ```bash
    host$ ./container up
    ```

4.  To run unit and functional tests for an app:

    ```bash
    host$ ./container run-tests --pytest-args -v --include-functional --no-xvfb plinth/modules/{app name}
    ```

5.  SSH into the running container with the following command:

    ```bash
    host$ ./container ssh
    ```

6. The default distribution used by the container script is "testing", but you
   can choose a different distribution (e.g. "stable") in two ways.

   1. Using an environment variable.

   ```bash
   host$ DISTRIBUTION=stable ./container up
   host$ DISTRIBUTION=stable ./container ssh
   ```

   ```bash
   host$ export DISTRIBUTION=stable
   host$ ./container up
   host$ ./container ssh
   ```

   2. Using the `--distribution` option for each command.

   ```bash
   host$ ./container up --distribution=stable
   host$ ./container ssh --distribution=stable
   ```

#### Using after Setup

After logging into the container, the source code is available in `/freedombox`
directory:

```bash
guest$ cd /freedombox
```

Run the development version of FreedomBox Service in the container using the
following command. This command continuously deploys your code changes into the
container providing a quick feedback cycle during development.

```bash
guest$ freedombox-develop
```

If you have changed any system configuration files during your development,
you will need to run the following to install those files properly on to the
system and their changes to reflect properly.

```bash
guest$ sudo ./setup.py install
```

Note: This development container has automatic upgrades disabled by default.

#### Troubleshooting

* Sometimes `host$ ./container destroy && ./container up` doesn't work. In such
  cases, try to delete the hidden `.container` folder and then `host$
  ./container up`.
* Not all kinds of changes are automatically updated. Try `guest$ sudo mount -o
  remount /freedombox`.
* I am getting an error that says `lo` is not managed by Network Manager
  * By default, Network Manager will not touch any interface mentioned in
    `/etc/network/interfaces`. <sup>[(src)][DebianNetworkManager]</sup>
    To workaround this error, you must override Network Manager's behavior.
    <sup>[(src)][GloballyManagedDevices]</sup>

    ```
    # On host machine
    $ sudo touch /etc/NetworkManager/conf.d/10-globally-managed-devices.conf
    $ sudo service network-manager restart
    $ ./container destroy && ./container up
    ```

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[DebianNetworkManager]: https://wiki.debian.org/NetworkManager#Wired_Networks_are_Unmanaged
[GloballyManagedDevices]: https://askubuntu.com/a/893614

### Using Vagrant

Use VirtualBox and Vagrant if for some reason the container option is not
suitable, such as when you are running non-GNU/Linux machine or a non-systemd
machine.

#### For Debian GNU/Linux and Derivatives

1. Install Git, Vagrant and VirtualBox using apt.

   ```bash
   $ sudo apt install git virtualbox vagrant
   ```

##### Installing VirtualBox manually

1. Add Oracle's key to apt's list of accepted keys.

   ```bash
   $ sudo wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -
   ```

2. Create a file under /etc/apt/sources.list.d/ for virtualbox package.


   ```bash
   $ sudo touch /etc/apt/sources.list.d/virtualbox.list
   ```

3. Add the relevant source for your Debian/derivative distribution into the above file.

Example for Buster:
   ```
   deb https://download.virtualbox.org/virtualbox/debian buster contrib
   ```

4. Search and install the latest virtualbox package.

   ```bash
   $ apt search virtualbox

       # virtualbox-6.1
       # virtualbox-6.0

   $ sudo apt install virtualbox-6.1
   ```

#### For Other GNU/Linux Distributions or *BSDs

1. Install Git, Vagrant and VirtualBox using your favourite package manager.

#### For macOS

1. Install [Homebrew](https://brew.sh/).

2. Install Git, VirtualBox and Vagrant using Homebrew.

   ```bash
   $ brew install git
   $ brew cask install virtualbox
   $ brew cask install vagrant
   ```

#### For Windows

1. Install [Git](https://git-scm.com/download/windows),
   [VirtualBox](https://www.virtualbox.org/wiki/Downloads) and
   [Vagrant](https://www.vagrantup.com/downloads.html) from their respective
   download pages.

2. Tell Git to use Unix line endings by running the following in Git Bash.

   ```bash
   host$ git config --global core.autocrlf input
   ```

3. Run all the following commands inside Git Bash.

#### Setting Up Development Environment Using Vagrant

Vagrant is a free software command line utility for managing the life cycle of
virtual machines. The FreedomBox project provides ready-made virtual machines
(VMs) for use with Vagrant. These images make setting up an environment for
FreedomBox development rather simple: You can edit the source code on your host
and immediately see the effects in the running VM. The entire setup is automatic
and requires about 4.5 GB of disk space.

1.  Checkout FreedomBox Service (Plinth) source code using Git.

    ```bash
    host$ git clone https://salsa.debian.org/freedombox-team/freedombox.git
    host$ cd freedombox
    ```

2.  To download, setup, run, and configure a VM for FreedomBox development using
    Vagrant, simply execute in your FreedomBox Service (Plinth) development
    folder:

    ```bash
    host$ vagrant up
    ```

3.  SSH into the running vagrant box with the following command:

    ```bash
    host$ vagrant ssh
    ```

#### Using the Virtual Machine

After logging into the virtual machine (VM), the source code is available in
/vagrant directory:

```bash
vm$ cd /vagrant
```

Run the development version of FreedomBox Service (Plinth) from your source
directory in the virtual machine using the following command. This command
continuously deploys your code changes into the virtual machine providing a
quick feedback cycle during development.

```bash
vm$ sudo -u plinth /vagrant/run --develop
```

If you have changed any system configuration files during your development,
you will need to run the following to install those files properly on to the
system and their changes to reflect properly.

```bash
vm$ sudo ./setup.py install
```

Note: This development virtual machine has automatic upgrades disabled by
default.


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## Making/keeping FreedomBox international

### Marking text for translation

To mark text for translation, FreedomBox uses Django's translation strings. A
module should e.g. `from django.utils.translation import gettext as _` and wrap
user-facing text with `_()`. Use it like this:

```python
message = _('Application successfully installed and configured.')
```

See [Django
documentation](https://docs.djangoproject.com/en/3.1/topics/i18n/translation/)
for more details.

### Translating literals (contributing translations)

The easiest way to start translating is with your browser, by using
[Weblate](https://hosted.weblate.org/projects/freedombox/plinth/).
Your changes will automatically get pushed to the code repository.

Alternatively, you can directly edit the `.po` file in your language directory
`Plinth/plinth/locale/` and create a pull request (see [CONTRIBUTING.md](CONTRIBUTING.md)).
In that case, consider introducing yourself on #freedombox IRC (irc.debian.org),
because some work may have been done already on the [Debian translators
discussion lists](https://www.debian.org/MailingLists/subscribe)
or the Weblate localization platform.

For more information on translations: https://wiki.debian.org/FreedomBox/Translate


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## Testing

### Running Tests

To run all the standard unit tests in the container/VM:

```bash
guest$ py.test-3
```

Another way to run tests (not recommended):

```bash
guest$ ./setup.py test
```

To run a specific test function, test class or test module, use pytest filtering
options. See pytest documentation for further filter options.

**Examples:**

```bash
# Run tests in a directory
guest$ py.test-3 plinth/tests

# Run tests in a module
guest$ py.test-3 plinth/tests/test_actions.py

# Run tests of one class in test module
guest$ py.test-3 plinth/tests/test_actions.py::TestActions

# Run one test in a class or module
guest$ py.test-3 plinth/tests/test_actions.py::TestActions::test_is_package_manager_busy
```

Some tests are skipped by default:
* tests that need root privileges,
* functional tests (they need additional preparation to run. See next section),
* tests that take much time to run.

Use `sudo` to run the ones that need root access:
```bash
guest$ sudo py.test-3
```

To force functional tests and tests that take long to run, set the environment
variable EXTENDED_TESTING=1:

```bash
guest$ EXTENDED_TESTING=1 py.test-3
```

To really run all tests, combine sudo with EXTENDED_TESTING:

```bash
guest$ sudo EXTENDED_TESTING=1 py.test-3
```

### Running the Test Coverage Analysis

To run the coverage tool in the container/VM:

```bash
guest$ py.test-3 --cov=plinth
```

To collect HTML report:

```bash
guest$ py.test-3 --cov=plinth --cov-report=html
```

Invoking this command generates a HTML report to the `htmlcov` directory.
`index.html` presents the coverage summary, broken down by module. Data columns
can be sorted by clicking on the column header. Clicking on the name of a
particular source file opens a page that displays the contents of that file,
with color-coding in the left margin to indicate which statements or branches
were executed via the tests (green) and which statements or branches were not
executed (red).


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### Functional Tests

#### Install Dependencies

##### For running tests inside the container

Inside the container run

```bash
guest$ cd /freedombox ; sudo plinth/tests/functional/install.sh
```

##### For running tests inside the VM

From the host, provision the virtual machine with tests:

```bash
host$ vagrant provision --provision-with tests
```

##### For running tests on host machine

Follow the instructions below to run the tests on host machine. If you wish
perform the tests on host machine, the host machine must be based on Debian
Buster (or later).

```bash
host$ pip3 install splinter
host$ pip3 install pytest-splinter
host$ pip3 install pytest-xdist  # optional, to run tests in parallel
host$ sudo apt install firefox
host$ sudo apt install xvfb python3-pytest-xvfb  # optional, to avoid opening browser windows
host$ sudo apt install smbclient  # optional, to test samba
```

- Install the latest version of
  [geckodriver](https://github.com/mozilla/geckodriver/releases). It is usually
  a single binary which you can place at `/usr/local/bin/geckodriver` .
  Geckodriver will use whichever binary is named 'firefox' for launching the
  browser and interacting with it.

#### Run FreedomBox Service

*Warning*: Functional tests will change the configuration of the system
 under test, including changing the hostname and users. Therefore you
 should run the tests using FreedomBox running on a throw-away VM.

The VM should have NAT port-forwarding enabled so that 4430 on the
host forwards to 443 on the guest. From where the tests are running, the web
interface of FreedomBox should be accessible at https://localhost:4430/.

To run samba tests, port 4450 on the host should be forwarded to port 445
on the guest.

#### Setup FreedomBox Service for tests

Via Plinth, create a new user as follows:

* Username: tester
* Password: testingtesting

This step is optional if a fresh install of Plinth is being tested. Functional
tests will create the required user using FreedomBox's first boot process.

#### Running Functional Tests

If you are testing a VM using NAT, and running the tests on the host,
then you need to specify the URL and ports:
```bash
host$ export FREEDOMBOX_URL=https://localhost:4430 FREEDOMBOX_SSH_PORT=2222 FREEDOMBOX_SAMBA_PORT=4450
```

You will be running `py.test-3`.

```bash
guest$ py.test-3 --include-functional
```

The full test suite can take a long time to run (more than an hour). You can
also specify which tests to run, by specifying a mark:

```bash
guest$ py.test-3 -m essential --include-functional
guest$ py.test-3 -m mediawiki --include-functional
```

If xvfb is installed and you still want to see browser windows, use the
`--no-xvfb` command-line argument.

```bash
guest$ py.test-3 --no-xvfb -m mediawiki --include-functional
```

Tests can also be run in parallel, provided you have the pytest-xdist plugin
installed.

```
$ py.test-3 -n 4 --dist=loadfile --include-functional -m essential
```


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## Documentation

### Building the User Documentation Separately

FreedomBox Service (Plinth) man page is built from DocBook source in the `doc/`
directory. FreedomBox manual is downloaded from the wiki is also available
there. Both these are build during the installation process.

To build the documentation separately, run:

```bash
guest$ make -C doc
```

### Building Developer documentation

See [README.rst](doc/dev/README.rst) in `doc/dev` directory.


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## Submitting your changes

See [CONTRIBUTING.md](CONTRIBUTING.md) for information how to best contribute code.


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## Miscelanea

### Styling

FreedomBox uses Bootstrap as the CSS library for basic styling. However,
Bootstrap seems to encourage writing CSS within HTML by adding "utility"
classes. This is a bad practice that violates the separation of semantics from
presentation. It also leads to repetition of code that further leads to
inconsistencies. These utility classes must be used sparingly. Instead, CSS must
be written separately either for a specific page or for the entire interface
aiming for reuse.

### Application Icons

When adding a new App into FreedomBox, an icon is needed to represent the app in
the application view and for shortcuts in the front page. Follow these
guidelines for creating an app icon:

- Use SVG format.
- Keep the size and complexity of the SVG minimal. Simplify the graphic if
  necessary.
- Units for the entire document should be in pixels.
- View area should be 512x512 pixels.
- Background should be transparent.
- Leave no margins and prefer a square icon. If the icon is wide, leave top and
  bottom margins. If the icon is tall, leave left and right margins.

### Team Coordination

The project team coordinates by means of bi-weekly [audio
calls](https://wiki.debian.org/FreedomBox/ProgressCalls) and IRC discussions on
#freedombox-dev at oftc.net.

### Other Development Informations

* Generic [contribution overview](https://wiki.debian.org/FreedomBox/Contribute)
  * [How to create apps for FreedomBox (Developer Manual)](https://docs.freedombox.org)
  * User Experience [design](https://wiki.debian.org/FreedomBox/Design)
  * [Code contribution](https://wiki.debian.org/FreedomBox/Contribute/Code)


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Here is CONTRIBUTING.md:

# Contributing
Here are some contributing guidelines for authors and reviewers of code changes.
The goal is a readable log of code changes, to enhance transparency of their
purpose and simplify debugging. Consider these guidelines as best practices, not
as absolute rules - we're all learning by doing, and imperfect changes and
commits are much better than none at all. For an introduction how to edit and
test the code, have look into the HACKING.md file. Note that you need some basic
understanding of Git to contribute; there are many tutorials in the Internet
that we cannot repeat here.


Naming conventions:
* 'Code change', 'patch', and 'commit' are used interchangeably.
* 'Author' and 'contributor' are used interchangeably.
* Git 'log' and 'history' are used interchangeably.
* PR, MR - pull request and merge request, used interchangeably.
* 'Merging' often means 'applying a patch to git history' in a general sense,
  not literal execution of the command `git merge`.


# For authors of patches
* If you would like to contribute, but are unsure what to do, just ask. There
  are usually also issues tagged as 'Contributor Invite' or 'beginner', which
  might be a good starting point to work on and have a known solution. Also,
  other developers are ready to guide you on the implementation for such tasks.
  Feel free to pickup a task from the issue by announcing it on the issue or by
  creating a new issue for whatever task you are going to work on.
* To get your changes included, you must open a merge request (MR) and get them
  reviewed. Briefly, fork the repository to your account, create a branch, edit
  code, commit and push there. Then you can create a merge request on the main
  repository.
* Before committing your changes ensure that your code conforms to base code
  hygiene by running tests (see HACKING.md) and the automatic code formatting
  tools `yapf` and `isort`. Please check also with `flake8`.
* Please include one single feature per merge request, to keep the review simple
  and focused on one topic. (This might still mean hundreds of lines of code.)
  Use a branch other than `master`, so you can create multiple merge requests
  and still keep merging from `master`. Depending on the complexity of your
  merge request, it may take a while until it is reviewed and merged.
* Keep your commits organized logically and as small as possible. If commit B
  fixes a mistake in commit A, both of which are part of the same merge request,
  combine them into a single commit. If commit A introduces a single logical
  change but breaks existing functionality and then commit B rectifies it, then
  also combine the two commits. This is to ensure that the source code can be
  checked out at any revision and used (such as during git bisect). If there are
  two unrelated changes in the same commit, split them to into separate commits.
  See Git documentation on how to merge, split and reorder commits.
* Please create meaningful commit messages, by following common guidelines:
    * Multiple lines are allowed if it makes the message clearer.
    * Separate the first subject line from the text body with a blank line.
	* Add the component you changed as the first word in the subject line.
    * Wrap the text at 72 characters.
    * Use the body to explain what your changes do, and maybe why and how it is
      achieved (the main idea).
	* Look into the git log to get an idea.
	* If it exists, mention the issue number.
	* End the message with a "Signed-off-by", see next entry.
* Consider adding `Signed-off-by: YOUR NAME <YOUR EMAIL>` into your commit
  message. With this, you explicitly certify that you have the rights to submit
  your work under the project's license (see LICENSES file) and that you agree
  to a [Developer Certificate of Origin](http://developercertificate.org/).
* If (part of) your code changes were inspired or plainly copied from another
  source, please indicate this in the merge request, so the reviewer can handle
  it.
* If your merge request is not ready for merging yet, the title of your merge
  request must start with
  `WIP:`
* If a reviewer asks for changes to your merge request, perform the changes as
  requested or provide clarification. Close the discussion threads so that the
  reviewer knows that it is ready for another round of review.
* Newer changes addressing review comments should go into the old commits which
  are being changed. For example, if there is a security problem with one of
  your commits, the commit should be edited instead of introducing a new commit
  with fix for it. After a merge, if a developer checks out any revision, it
  could not contain serious problem. See Git documentation on how to merge,
  split, reorder commits and how to force push your branches after altering
  commits.
* Have fun contributing :)


# For reviewers of patches

## How to review the work of others
* Be nice to contributors and give them opportunities to learn. Explain the
  reasons if you ask for changes instead of silently changing things yourself
  (unless trivial). This also saves you time in the future.
* Reviewers are expected to ensure that a contributor's work:
    * Does not break the current code. The code base should always be in a
	  usable state, without throwing (non-handled) errors. We also strive to
	  keep the code base in a release-worthy state.
    * Has no security issues.
    * Follows coding standards of the project
	  (mainly [PEP-8](https://www.python.org/dev/peps/pep-0008/)).
    * Is properly internationalized.
* Your main job is to make sure that the work runs as expected, by thoroughly
  testing the patch. New authors are usually not familiar with all areas of
  impact and may not have tested all cases. It is okay to rely on tests done by
  trusted authors, if they specify the specific cases they tested.
* When merging work from others, add this line to the commit message:
  `Reviewed-by: YOUR NAME <YOUR EMAIL>`.
* Some patches require knowledge of multiple technologies. If you are not
  familiar with all of them, it's fine to review only the portions you
  understand (and indicate them clearly). Then ask others for further review.
* For major architectural changes/decisions, consult others in the project
  before merging.
* You may make some minimal or obvious changes to the work before merging. If
  so, tell the contributor (and others) about your edits.
* In case more fundamental changes are necessary, or if the contributor is new,
  try to encourage them to make changes by giving appropriate feedback. This is
  a major way how we mentor new contributors.
* Any merge request whose title starts with `WIP:` cannot be merged. Communicate
  with the author on what the pending changes are. Get the author to complete
  them or complete them yourself in case of an emergency.
* Have fun reviewing :)


## Use of Git
* Avoid plain `git merge`, and use rebasing instead, to avoid merge commits.
  This keeps the history much more readable for others to understand, review,
  bisect and rollback.
* When merging patches with multiple commits, try to make each patch meaningful.
  For example, fixes to patches should be squashed into the original patch.
  Security issues and other serious issues should be avoided in intermediate
  patches – even if they are fixed in later patches.


## Use of GPG
* Sign all commits with GPG. This means avoiding GitLab's fancy merge and rebase
  buttons and doing it locally, where your private key is.
* In case a contributor signed with GPG, rebasing will strip it away. To
  compensate, put your GPG signature on the rebased commits. Given that we have
  to actually verify the signatures on each commit and the contributor may not
  be in our web of trust (as we allow anonymous contributions). In such cases,
  GPG signatures of the reviewers are more important.
* Get your GPG key signed by other reviewers or Debian Developers, to enable
  verification of your signed commits.


## (When) can I commit without review?
* Even if you have commit access, you should get your patches reviewed by the
  other reviewers.
* Certain patches do not require review. These include updating the manual, typo
  fixes, and creating new locales.