pkglic 1.0.3

Script to get the licenses of components used by js, py or c# apps.

PkgLic

The purpose of this helper app is to make it fast and easy to get an understanding of which open source licenses you are using in your application.

This is done by querying the respective package manager for the meta data rather than what is installed locally, as your build machines may not want/need all the packages installed and you'll also save time by not having to download the bulk of the packages.

The intention is to run it in your build pipeline, and at least you get a list of the components you use (as per your requirements files) and their licenses. With a small bit of trickery you can update some wiki page to keep an up to date list of packages.

The script handles requirements.txt (python), package.json (javascript), *.csproj (C#/nuget) and packages.config (C#/nuget).

Basic operation is to invoke the script with some file

pkglic -f requirements.txt

and get an output with package names and their license. There are some more switches supported.

pkglic - (c) Jesper Hogstrom 2021.

usage: pkglic [-h] -f file [file ...] [-o {0,1,2,3}] [-t {py,js,cs,nu}]
              [-u [UNWANTED [UNWANTED ...]]] [-v]

optional arguments:
  -h, --help            show this help message and exit
  -f file [file ...], --files file [file ...]
                        input files to scan.
  -o {0,1,2,3}, --order {0,1,2,3}
                        Which fields to use to sort output; 0 - type, name, 1:
                        license, name, 2: type, license, 3: group by license.
  -t {py,js,cs,nu}, --type {py,js,cs,nu}
                        Assume <type> for all <files> if not guessable.
  -u [UNWANTED [UNWANTED ...]], --unwanted [UNWANTED [UNWANTED ...]]
                        Exit with errorlevel on these license types.
  -v, --verbose         Increase verbosity.

Installation

Either install it from pypi

pip install pkglic

or download the sources and make sure your environment has the required packages installed (pip install -r requirements.txt) and invoke the script from wherever you store it. You may for instance want to check it in with the rest of your build tools.

Supported formats

Python

Any file path containing "requirements.txt" will be analyzed as a requirements file as supported by pip.

http://pypi.org is used to fetch the meta data.

Javascript

Any file path containing "package.json" will be analyzed as a package.json file. Only the "dependencies" block will be checked!

https://npmjs.org is used to fetch the meta data.

Nuget

Any file containing ".csproj" will be analyzed as a C# project and the nuget packages extracted for analysis.

Any file containing "packages.config" will be analyzed as a nuget packages file (an older way to specify nuget dependencies).

https://nuget.org is used to fetch the meta data.

Hard check on licenses

Some projects prefer to avoid certain OSS licenses. This was actually the main reason for writing the tool. There are many ways to accomplish such a verification, including using the switch -u or --unwanted - for instance -u GPL or -unwanted "MIT License".

Adding the -u switch will first print all packages and their licenses, then print out all packages that match any unwanted license and finally terminate with an error code, breaking the build.

Updating wiki pages

All output is written to stdout, so something like

pkglic -f requirements.txt | tee /tmp/licenses_in_use
wikiupdater --host wiki.intranet --target-page licenses --upload /tmp/licenses_in_use

will do the trick (assuming you have a tool called wikiupdater etc etc).

Scanning all files in a tree

If you have scattered your requirements.txt throughout your source tree, and even separated the development packages into dev-requirements.txt, you can use the existing tools to find all files and then add them to the command lline using xargs.

find -iname '*requirements.txt' | xargs pkglic -f

This can of course be combined with tee.

find -iname '*requirements.txt' | xargs python pkglic -f | tee /tmp/licenses_in_use

Note that adding multiple files may result in duplication of packages, if they appear in multiple files. This may add some value, as you will see in how many places (but not which places) you require each package. If that is more information than you need, then remove the duplicate lines with uniq.

find -iname '*requirements.txt' | xargs pkglic -f | uniq

Modifying the output

If you are reasonably satisfied with the standard output format, but want to tweak it just a little, you can for instance remove the type indicator easily using sed.

find -iname '*requirements.txt' | xargs pkglic -f | | sed -e "s/\[.*\] //"

For heavy duty modification, add --json <file> to the argument list. That will yield standard output on stdout and a list of dictionaries in <file>. This should be easy enough to import into some other tool to generate a nifty report or a credits page.

pkglic -f requirements.txt --json licenses.json
generate_credits -i licenses.lic > credits-html

(assuming you have a tool generate_credits etc etc)

The output file has the following format:

{
    "generator": "pkglic (c) Jesper Hogstrom 2021",
    "generated": "date of execution in iso-format",
    "packages":
    [
        {
            "name": <packageid>,
            "version": <version>,
            "license": <license type or filename with license (prefixed by 'file: ')>,
            "licenseurl": <url with license text or null>,
            "author": <author or null>,
            "author_email": <author's email or null>,
            "home_page": <url to project's home page or null>,
            "summary": <summary or null>
        },
        ...
    ]
}

License types

The license type will be set to whatever the package specifies. However, in some cases the license cannot be determined. If so, the following applies:

• The meta data could not be downloaded: 404_NOT_FOUND
• The license node not present: NOT_SPECIFIED