Unshielded Access Control

[emnul]

Types of changes

• New feature (non-breaking change which adds functionality)
• Documentation Update (if none of the other choices apply)

Fixes #89

This pull request adds an unshielded AccessControl module to the Compact contracts library. Some notable design decisions:

• Implemented an _unsafeGrantRole function to allow users to grant roles to a ContractAddress
• Did not implement an _unsafeRevokeRole function since I didn't see any major security concerns with implementing revokeRole and _revokeRole as is
• No RoleData struct. Since struct types in Compact cannot contain ledger data types I decided to instead create a _operatorRoles ledger variable and _adminRoles ledger variable to Map roles -> accounts -> permissions and roles -> admin roles respectively.

PR Checklist

• I have read the Contributing Guide
• I have added tests that prove my fix is effective or that my feature works
• I have added documentation of new methods and any new behavior or changes to existing behavior
• CI Workflows Are Passing

[andrew-fleming]

Great start, @emnul! The design looks good. I left some comments

[emnul]

Initial review of changes

[emnul]

@andrew-fleming after playing around with the contract it seems that setting the DEFAULT_ADMIN_ROLE to 0 in initialize() is redundant. We could potentially get rid of the Initializable import and checks entirely. I like the idea of getting rid of this and instructing users that if they want a custom a DEFAULT_ADMIN_ROLE they would need to implement the Initializable module along with all of its checks. I don't believe setting a custom DEFAULT_ADMIN_ROLE is common enough to justify keeping all of the Initializable boilerplate, but what do you think?

[andrew-fleming]

Improvements look outstanding! I left a few more suggestions (super minor, with the code examples). Otherwise, I think we're good to go 🚀

[emnul]

Completed review of most recent changes

[andrew-fleming]

LGTM!