jk_licenses

Introduction

This python module provides OS licenses.

Information about this module can be found here:

• github.org
• pypi.python.org

Why this module?

It is quite tiresome to maintain various instances of a program using all the same data. Therefore the functionality of providing a set of licenses has been factored out into this module jk_licenses.

This module is intended as a building block in module/package/application management.

What licenses are supported?

The following table provides an overview about the licenses available in this module as well as their identifiers and variables:

Main license ID	Alternative license IDs	Human readable name	Placeholders
0BSD		Free Public License 1.0.0
AGPLv3	AGPL-3.0, AGPLv3	GNU Affero General Public License version 3
Apache2	Apache2	GNU Lesser General Public License version 3
BSD2	BSD2	The 2-Clause BSD License	year, copyrightHolder
BSD3	BSD3	The 3-Clause BSD License	year, copyrightHolder
GPLv3	GPL-3.0, GPLv3	GNU General Public License version 3
LGPLv3	LGPL-3.0, LGPLv3	GNU Lesser General Public License version 3
MIT		MIT License	year, copyrightHolder
Proprietary	proprietary	Propriertary License	year, copyrightHolder

How to use this module

Import this module

Please include this module into your application using the following code:

import jk_licenses

What this module provides

The python module jk_licenses provides a constant (= global variable) and three classes:

• constant LICENSE_MGR that provides an instance of LicenseMgr
• class LicenseMgr that maintaines the available licenses
• class License that represents a single license
• class VariableDef: licenses may contain VariableDef to represent placeholders within the license text

The class License

Each license is represented by an instance of class License.

This section gives a short explanation about the structure of an instance of License in pseudocode notation.

This class provides the following properties:

• str name : The human readable name of this license.
• str[] licenseIDs : A list of strings that are associated with this license as identifiers. The first license ID is always the main license ID.
• str licenseID : The main license ID that identifies this license.
• str classifier : A string that contains a possible python trove classifier. See pypi.org for details.
• VariableDef[] variableDefinitions : A list of variable definitions. These give information about placeholders to fill if you want to produce the license text.

This class provides the following methods:

• str produceText(dict<str,str> variableAssignments) : Produce the license text. If a license has placeholder, you need to provide a value for every placeholder. An exception is thrown on error.
• void validateVariableAssignments(dict<str,str> variableAssignments) : You can check if data is provided for all placeholders as required using this method. An exception is thrown on error.

You do not need to instantiate this class yourself. Instead you obtain an instance of this class through the license manager.

The class LicenseMgr

The license manager is represented by an instance of class LicenseMgr.

This section gives a short explanation about the structure of the license manager in pseudocode notation.

This class provides the following properties:

• str name : The human readable name of this license.
• str[] licenseIDs : A list of strings that are associated with this license as identifiers. The first license ID is always the main license ID.
• str licenseID : The main license ID that identifies this license.
• str classifier : A string that contains a possible python trove classifier. See pypi.org for details.
• VariableDef[] variableDefinitions : A list of variable definitions. These give information about placeholders to fill if you want to produce the license text.

This class provides the following methods:

• str produceText(dict<str,str> variableAssignments) : Produce the license text. If a license has placeholder, you need to provide a value for every placeholder. An exception is thrown on error.
• void validateVariableAssignments(dict<str,str> variableAssignments) : You can check if data is provided for all placeholders as required using this method. An exception is thrown on error.

You do not need to instantiate this class yourself. Instead you access a default license manger instance using the constant (= variable) LICENSE_MGR this module provides.

Access the licenses

You can display the licenses that are available via the license manager. Example:

for licenseID in LICENSE_MGR.mainLicenseIDs:
	print(licenseID)

If you specify the licenses available you can use the license identifiers to access a license object. Example:

license = LICENSE_MGR.getLicense("0BSD")
print(license.name)

Producing a license text

Once you have a license object obtained from the license manager you can then produce the license text. Example:

license = LICENSE_MGR.getLicense("0BSD")
licenseText = license.produceText()

And with arguments:

license = LICENSE_MGR.getLicense("MIT")
licenseText = license.produceText({
	"year": 2020,
	"copyrightHolder": "Jürgen Knauth"
})

Contact Information

This work is Open Source. This enables you to use this work for free.

Please have in mind this also enables you to contribute. We, the subspecies of software developers, can create great things. But the more collaborate, the more fantastic these things can become. Therefore Feel free to contact the author(s) listed below, either for giving feedback, providing comments, hints, indicate possible collaborations, ideas, improvements. Or maybe for "only" reporting some bugs:

• Jürgen Knauth: jknauth@uni-goettingen.de, pubsrc@binary-overflow.de

License

This software is provided under the following license:

• Apache Software License 2.0