Root data source

[chait-slim]

Relevant tickets for reference:
#4396 (comment)
#3937

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[another-rex]

These source and source_test.yaml should be done in separate PRs, as they are imported immediately after being merged.

[chait-slim]

Done. The other PR: #4548

[another-rex]

Thanks!

[another-rex]

/gcbrun

[another-rex]

Please have a look at the linting errors. (You can run this locally with make lint)

[another-rex]

Also, tests seem to be failing:

OK
+ poetry run python -m unittest osv.purl_helpers_test
.F
======================================================================
FAIL: tests_package_to_purl (osv.purl_helpers_test.PurlHelpersTest.tests_package_to_purl)
Test PURL generation.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/workspace/osv/purl_helpers_test.py", line 140, in tests_package_to_purl
    self.assertEqual('pkg:generic/root/%40root%2Flodash',
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                     purl_helpers.package_to_purl('Root', '@root/lodash'))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: 'pkg:generic/root/%40root%2Flodash' != 'pkg:generic/root/%40root/lodash'
- pkg:generic/root/%40root%2Flodash
?                         ^^^
+ pkg:generic/root/%40root/lodash
?                         ^

you can run it locally with the poetry run python -m unittest osv.purl_helpers_test , or with make all-tests