1192801 - Remove MPL boilerplate text since it's unnecessary under MPLv2 with LICENSE.txt

Status: RESOLVED FIXED

(Tree Management :: Treeherder, defect)

Description

[Ed Morley [:emorley]]

So with v1 of the MPL, it was written into the license that people must include the boilerplate text at the top of each file.

However it turns out that with v2 of the MPL, this is now optional, even if the structure of the file allows for adding the boilerplate (see exhibit A of https://www.mozilla.org/MPL/2.0/).

Unfortunately much of the documentation hasn't been updated properly to reflect this (I've just filed bug 1192790 to get this corrected). This unfortunately gave the impression we had to add the boilerplate text at the top of each file in bug 1090689.

In addition, back then we had third-party Python packages checked into the repo (pre bug 1155160) as well as the UI third party assets scattered around (pre bug 1159670) - so a per-file probably made more sense.

However the boilerplate:
* breaks a few files (eg Heroku's runtime.txt)
* makes for busy-work when updating auto-generated files (eg the django migrations file), since it has to be added back each time
* causes false positives in grep results
* adds to the line count/clutter when editing files

Therefore I think we should now just remove it, and rely on LICENSE.txt - with perhaps an additional LICENSE.txt in the ui/vendor/ directory to mention that files under there are not covered by the repo root licence file.

Comment 1

[Ed Morley [:emorley]]

Kuma takes a similar approach fwiw:
https://github.com/mozilla/kuma

Comment 2

[Ed Morley [:emorley]]

And these projects don't include per-file licenses either (they are using BSD, which at least in the case of zamboni was to avoid MPL v1's old boilerpate requirement https://groups.google.com/forum/#!topic/mozilla.legal/vSr8Gat9LAY):
https://github.com/mozilla/zamboni
https://github.com/mozilla/kitsune (support.mozilla.o)
https://github.com/mozilla/mozillians
https://github.com/mozilla/pontoon

Comment 3

[Ed Morley [:emorley]]

Attachment: Remove per-file MPL boilerplate since it's unnecessary

Given that:
* several other projects don't use per file licences (see comment 1 / comment 2)
* the MPL 2.0 terms state that as long as a LICENSE file is present, the per-file header text is not required (see "Exhibit A" at the end of https://www.mozilla.org/MPL/2.0/)
* whilst including per-file boilerplate is still suggested on https://www.mozilla.org/MPL/headers/ , this is more relevant for traditional software rather than for webdev projects, for the reasons in bug 1192790 comment 5
* Gerv has confirmed we won't be asked to add the per-file licences back (bug 1192790 comment 6)

...IMO we should just remove them.

Comment 4

[Treeherder GitHub Bugbot]

Commits pushed to master at https://github.com/mozilla/treeherder

https://github.com/mozilla/treeherder/commit/ad2048b83ff82e85d15d4d10774571470b66346a
Bug 1192801 - List the full MPL v2 license in LICENSE.txt

Since the short form is just intended for use in individual files.

https://github.com/mozilla/treeherder/commit/90ba77e596e2c3329e0b840fe45e661e8e2a0370
Bug 1192801 - Remove per-file MPL boilerplate since it's unnecessary

The MPL 2.0 terms state that as long as a LICENSE file is present, the
per-file header text is not required. See "Exhibit A" at the end of:
https://www.mozilla.org/MPL/2.0/