Linter rule to check for existence of the License file

[ramya-rao-a]

All our packages should have a License file with the same content as https://github.com/Azure/azure-sdk-for-js/blob/main/LICENSE
We should have a linter rule that checks for this.

Code pointers:

• Set up your dev env if you have not already
• ESLint Plugin source package
• Once you have the rule in place, add the License file to any package that is missing it in the same PR

[WeiJun428]

I am interested in resolving this issue. I think it is viable to check if the contents of LICENCE is identical, but to my knowledge, there is no way for eslint to check if a file exists. (refer eslint and stackoverflow) May I get suggestions to relevant resources that would be helpful?

[ramya-rao-a]

Fair point.

@deyaaeldeen, @witemple-msft, Any thoughts here?

[deyaaeldeen]

One idea: @witemple-msft was advocating to use dev-tool to do lint checks on our json files (e.g. package.json and tsconfig.json) because it will be more efficient/natural than using eslint. We could expand on this by making dev-tool also handle existence checks on certain files. To generalize this further, we could make it the entry point to linting (akin to how it handles the new testing stuff now).

Since this is a bit complicated, I suggest that @WeiJun428 ignores it for now.

@WeiJun428 if you're looking for suggestions on a next issue to work on, #15746 is pretty cool and I think we could use a 3rd party rule for it.

[ramya-rao-a]

Turns out this is a check we want to have for other language repos as well. Therefore, we will be having a separate issue Azure/azure-sdk-tools#2353 tracking this requirement such that we add this check in the pipeline instead of linter.

Thanks everyone!