Create group consistensy rules and detect consistensy errors at repositories of a group
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### Problem to solve
<!-- What problem do we solve? Try to define the who/what/why of the opportunity as a user story. For example, "As a (who), I want (what), so I can (why/value)." -->
Groups (and subgroups) tend to have many repositories which share common files that they should be consistent among many or all of them (e.g. LICENSE, CONTRIBUTING, `.gitlab/*_templates`). Depending on the scale of the group, this may be a lot of hustle for maintainers to manage and some overhead for new repositories, but this content is critical for community-friendly teams.
As a user who is responsible for a group's community, I want to be able to know what repositories of the group are not compliant with the community content I want to use, and ideally to have automated actions available in order to fix these inconsistencies.
### Intended users
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Personas are described at https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/
* [Cameron (Compliance Manager)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#cameron-compliance-manager)
* [Parker (Product Manager)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#parker-product-manager)
* [Delaney (Development Team Lead)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#delaney-development-team-lead)
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* [Sam (Security Analyst)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sam-security-analyst)
* [Rachel (Release Manager)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#rachel-release-manager)
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-->
This is indented for the Community Manager/Delaney (Development Team Lead)
### User experience goal
<!-- What is the single user experience workflow this problem addresses?
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The user should be able to use the UI/API to see if all repositories of a group have the same LICENSE.
Extra: The user should be able to use the UI/API to apply a common LICENSE (or .gitlab/*_templates) file to many or all repositories of a group
### Proposal
<!-- How are we going to solve the problem? Try to include the user journey! https://about.gitlab.com/handbook/journeys/#user-journey -->
- The user should be able to choose predefined or define rules consistency rules
- The rules can be either about repository contents or configuration
- The nature of the rules can be either generic or specific (i.e. "Files must exist and have same contents" -The user adds file paths- or "Repositories must have same LICENSE file")
- Gitlab should be able to detect rules violation on the repository default branch
- The user is the responsible to solve, ignore or whitelist rules violation (inconsistencies)
Extra:
- Given that the rule is violated by an update, propose the user to auto-solve (i.e. When the rule is "same-content", create automated MRs at the other repositories )
- Given a new repository, propose the user to auto-solve *
\* The use of a repository template that is being imported solves the new repo scenario, but the rest of the repositories must be updated by hand (event if that is a rebase) and depending the number of the repositories, the user may fail to do it consistently.
### Further details
<!-- Include use cases, benefits, goals, or any other details that will help us understand the problem better. -->
Right now I'm referring to standard community related files, but code related files (e.g. linter rules or for node projects `.nvmrc` files ) are a potential target for consistency rules.
Potential conflict could be the a subgroup with different rules ()
### Permissions and Security
<!-- What permissions are required to perform the described actions? Are they consistent with the existing permissions as documented for users, groups, and projects as appropriate? Is the proposed behavior consistent between the UI, API, and other access methods (e.g. email replies)?-->
The essential permissions are: Guest (read the files)
Extra (In the case of the automated MRs):
- Reporter: Create MRs as the user
### Documentation
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### Availability & Testing
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* Unit test changes
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### What does success look like, and how can we measure that?
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### What is the type of buyer?
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### Is this a cross-stage feature?
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### Links / references
issue