<!--
SPDX-FileCopyrightText: 2017 Free Software Foundation Europe e.V. <https://fsfe.org>
SPDX-License-Identifier: CC-BY-SA-4.0
-->
# reuse
[](https://pypi.python.org/pypi/reuse)
[](https://pypi.python.org/pypi/reuse)
[](https://api.reuse.software/info/github.com/fsfe/reuse-tool)
[](https://github.com/RichardLitt/standard-readme)
> reuse is a tool for compliance with the [REUSE](https://reuse.software/)
> recommendations.
- Documentation: <https://reuse.readthedocs.io> and <https://reuse.software>
- Source code: <https://github.com/fsfe/reuse-tool>
- PyPI: <https://pypi.python.org/pypi/reuse>
- REUSE: 3.0
- Python: 3.6+
## Background
Copyright and licensing is difficult, especially when reusing software from
different projects that are released under various different licenses.
[REUSE](https://reuse.software) was started by the
[Free Software Foundation Europe](https://fsfe.org) (FSFE) to provide a set of
recommendations to make licensing your Free Software projects easier. Not only
do these recommendations make it easier for you to declare the licenses under
which your works are released, but they also make it easier for a computer to
understand how your project is licensed.
As a short summary, the recommendations are threefold:
1. Choose and provide licenses
2. Add copyright and licensing information to each file
3. Confirm REUSE compliance
You are recommended to read [our tutorial](https://reuse.software/tutorial) for
a step-by-step guide through these three steps. The
[FAQ](https://reuse.software/faq) covers basic questions about licensing,
copyright, and more complex use cases. Advanced users and integrators will find
the [full specification](https://reuse.software/spec) helpful.
This tool exists to facilitate the developer in complying with the above
recommendations.
There are [other tools](https://reuse.software/comparison) that have a lot more
features and functionality surrounding the analysis and inspection of copyright
and licenses in software projects. The REUSE helper tool, on the other hand, is
solely designed to be a simple tool to assist in compliance with the REUSE
recommendations.
## Example demo
In this screencast, we are going to follow the
[tutorial](https://reuse.software/tutorial), making the
[REUSE example repository](https://github.com/fsfe/reuse-example/) compliant.
## Install
### Installation via pip
To install reuse, you need to have the following pieces of software on your
computer:
- Python 3.6+
- pip
You then only need to run the following command:
```bash
pip3 install --user reuse
```
After this, make sure that `~/.local/bin` is in your `$PATH`. On Windows, the
required path for your environment may look like
`%USERPROFILE%\AppData\Roaming\Python\Python39\Scripts`, depending on the Python
version you have installed.
To update reuse, run this command:
```bash
pip3 install --user --upgrade reuse
```
For full functionality, the following pieces of software are recommended:
- Git
- Mercurial 4.3+
### Installation via package managers
There are packages available for easy install on some operating systems. You are
welcome to help us package this tool for more distributions!
- Arch Linux (AUR): [reuse](https://aur.archlinux.org/packages/reuse/)
- Fedora: [reuse](https://apps.fedoraproject.org/packages/reuse)
- openSUSE: [reuse](https://software.opensuse.org/package/reuse)
- GNU Guix: [reuse](https://guix.gnu.org/packages/reuse-0.5.0/)
- NixOS: [reuse](https://nixos.org/nixos/packages.html?attr=reuse)
### Installation from source
You can also install this tool from the source code, but we recommend the
methods above for easier and more stable updates. Please make sure the
requirements for the installation via pip are present on your machine.
```bash
python3 setup.py install
```
## Usage
First, read the [REUSE tutorial](https://reuse.software/tutorial/). In a
nutshell:
1. Put your licenses in the `LICENSES/` directory.
2. Add a comment header to each file that says
`SPDX-License-Identifier: GPL-3.0-or-later`, and
`SPDX-FileCopyrightText: $YEAR $NAME`. You can be flexible with the format,
just make sure that the line starts with `SPDX-FileCopyrightText:`.
3. Verify your work using this tool.
Example of header:
```
# SPDX-FileCopyrightText: 2017 Free Software Foundation Europe e.V. <https://fsfe.org>
#
# SPDX-License-Identifier: CC-BY-SA-4.0
```
To check against the recommendations, use `reuse lint`:
```
~/Projects/reuse-tool $ reuse lint
[...]
Congratulations! Your project is compliant with version 3.0 of the REUSE Specification :-)
```
This tool can do various more things, detailed in the documentation. Here a
short summary:
- `addheader` --- Add copyright and/or licensing information to the header of a
file.
- `download` --- Download the specified license into the `LICENSES/` directory.
- `init` --- Set up the project for REUSE compliance.
- `lint` --- Verify the project for REUSE compliance.
- `spdx` --- Generate an SPDX Document of all files in the project.
### Run in Docker
The `fsfe/reuse` Docker image is available on
[Docker Hub](https://hub.docker.com/r/fsfe/reuse). With it, you can easily
include REUSE in CI/CD processes. This way, you can check for REUSE compliance
for each build. In our [resources for developers](https://reuse.software/dev/)
you can learn how to integrate the REUSE tool in Drone, Travis, GitHub, or
GitLab CI.
You can run the helper tool simply by providing the command you want to run
(e.g., `lint`, `spdx`). The image's working directory is `/data` by default. So
if you want to lint a project that is in your current working directory, you can
mount it on the container's `/data` directory, and tell the tool to lint. That
looks a little like this:
```bash
docker run --volume $(pwd):/data fsfe/reuse lint
```
You can also provide additional arguments, like so:
```bash
docker run --volume $(pwd):/data fsfe/reuse --include-submodules spdx -o out.spdx
```
### Run as pre-commit hook
You can automatically run `reuse lint` on every commit as a pre-commit hook for
Git. This uses [pre-commit](https://pre-commit.com/). Once you
[have it installed](https://pre-commit.com/#install), add this to the
`.pre-commit-config.yaml` in your repository:
```yaml
repos:
- repo: https://github.com/fsfe/reuse-tool
rev: latest
hooks:
- id: reuse
```
Then run `pre-commit install`. Now, every time you commit, `reuse lint` is run
in the background, and will prevent your commit from going through if there was
an error.
## Maintainers
- Carmen Bianca Bakker - <carmenbianca@fsfe.org>
## Contribute
Any pull requests or suggestions are welcome at
<https://github.com/fsfe/reuse-tool> or via e-mail to one of the maintainers.
General inquiries can be sent to <reuse@lists.fsfe.org>.
Interaction within this project is covered by the
[FSFE's Code of Conduct](https://fsfe.org/about/codeofconduct).
Starting local development is very simple, just execute the following commands:
```bash
git clone git@github.com:fsfe/reuse-tool.git
cd reuse-tool/
python3 -mvenv venv
source venv/bin/activate
make develop
```
You need to run `make develop` at least once to set up the virtualenv.
Next, run `make help` to see the available interactions.
## License
This work is licensed under multiple licences. Because keeping this section
up-to-date is challenging, here is a brief summary as of April 2020:
- All original source code is licensed under GPL-3.0-or-later.
- All documentation is licensed under CC-BY-SA-4.0.
- Some configuration and data files are licensed under CC0-1.0.
- Some code borrowed from
[spdx/tool-python](https://github.com/spdx/tools-python) is licensed under
Apache-2.0.
For more accurate information, check the individual files.