Managing license and copyright in Stack packages

All packages in the LSST Stack (EUPS-distributed packages installed with lsst_distrib and qserv_distrib, for example) are licensed under GPL-3.0 terms. This page describes the three aspects developers need to know to properly implement the GPL-3.0 license in Stack packages:

1. The LICENSE file

2. The COPYRIGHT file

3. License preambles in source files

For additional background information on licenses and copyright for LSST DM work, see the pages Licensing LSST DM source code and content and Copyrights for LSST DM work and the COPYRIGHT file.

The LICENSE file

Each Stack package must have a file called LICENSE at its root. You can find the LICENSE file in the stack_package template.

Be careful not to modify the LICENSE file.

Tip

Create a LICENSE file from Slack. Open a direct message with @sqrbot-jr and type:

create file

Then select General > GPLv3 LICENSE.

The COPYRIGHT file

Each Stack package must have a file called COPYRIGHT at its root where we record copyright assignments. See The COPYRIGHT file for information on how to format the COPYRIGHT file.

All DM developers are expected to participate in maintaining the COPYRIGHT file on behalf of your institution. Include additions to COPYRIGHT files as part of your regular pull requests. /legal/copyright.py is a script that may help maintain COPYRIGHT files.

Tip

Create a COPYRIGHT file from Slack. Open a direct message with @sqrbot-jr and type:

create file

Then select General > COPYRIGHT file.

License preambles in source files

The GPL-3.0 license requires each source file to have a preamble comment containing a license statement. This is the generic license preamble:

This file is part of {{ cookiecutter.package_name }}.

Developed for the LSST Data Management System.
This product includes software developed by the LSST Project
(https://www.lsst.org).
See the COPYRIGHT file at the top-level directory of this distribution
for details of code ownership.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.

Replace {{ cookiecutter.package_name }} with the repository’s name (afw, for example).

This preamble is available as a template.

Python preamble

The license preamble specifically for use in Python files is:

# This file is part of {{ cookiecutter.package_name }}.
#
# Developed for the LSST Data Management System.
# This product includes software developed by the LSST Project
# (https://www.lsst.org).
# See the COPYRIGHT file at the top-level directory of this distribution
# for details of code ownership.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

Replace {{ cookiecutter.package_name }} with the repository’s name (afw, for example).

Tip

Create a Python license preamble from Slack. Open a direct message with @sqrbot-jr and type:

create file

Then select Source license preambles > Python.

See also: Each Python file MUST contain the standard license preamble in the LSST DM Python Style Guide.

This preamble is also available as a template.

C++ preamble

The license preamble specifically for use in C++ source and header files is:

/*
 * This file is part of {{ cookiecutter.package_name }}.
 *
 * Developed for the LSST Data Management System.
 * This product includes software developed by the LSST Project
 * (https://www.lsst.org).
 * See the COPYRIGHT file at the top-level directory of this distribution
 * for details of code ownership.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

Replace {{ cookiecutter.package_name }} with the repository’s name (afw, for example).

Tip

Create a C++ license preamble from Slack. Open a direct message with @sqrbot-jr and type:

create file

Then select Source license preambles > C++.

This preamble is also available as a template.