feat: support union operator on BasePermission

[replygirl]

Description

👉 tl;dr: Lets you use | between permission instances, e.g. is_cool_color = IsBlue() | IsGreen()

• Added: BasePermission.__or__ instance method, which returns an OrPermission instance
• Added: OrPermission, inheriting from BasePermission
  • __init__ takes a tuple of BasePermission instances to be evaluated
  • has_permission returns True as long as has_permission returns True from any of its input permissions
  • message and on_unauthorized refer to the last failed permission

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Documentation

Issues Fixed or Closed by This PR

• closes Combining permissions with -OR- #2350
  • Per the discussion I am also into DRF's OperandHolder pattern. If folks are strongly opinionated I can take a stab at that instead

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).
  • Also fully tested on the job 👍

[botberry]

Thanks for adding the RELEASE.md file!

Here's a preview of the changelog:

---

Permissions can now be combined with the | operator to require the user pass either of the has_permission checks:

import strawberry
from strawberry.permission import PermissionExtension


@strawberry.type
class User:
    @strawberry.field(
        extensions=[
            PermissionExtension(
                # require auth AND (node is current user OR current user is staff)
                permissions=[IsAuthenticated(), IsExactUser() | IsStaff()]
            )
        ]
    )
    def ssn(self) -> str:
        return "555-55-5555"

Here's the tweet text:

🆕 Release (next) is out! Thanks to replygirl for the PR 👏

Get it here 👉 https://beta.strawberry.rocks/release/(next)

[erikwrede]

This looks like a great usability addition. I will conduct more thorough testing later, but for now, can you please add the following test cases so we don't accidentally break something later:

• two resolvers use the same OR filter -> directive duplication doesn't cause an error
• permutation of entries in the OR filter in two separate resolve (My preference is to use the same directive in this case and not create two separate directives, i.e. always AorB instead of AorB and BorA. We can sort this out by ordering the permission names lexicographically using sort)

How should we handle multiple ORs that are chained? Should the or-filter flat map them into a single filter ,or should there be nested OR-filters? In this case, there should also be test cases on schema generation

• More than 2 permissions disjuncted, (AorBorC)

[replygirl]

@erikwrede all sounds good! i'll have time to come back to this in the next few days

Should the or-filter flat map them into a single filter (my preferred option),or should there be nested OR-filters?

nesting is my instinct, because it seems supporting other operators would be more straightforward, but i'll think about it more and look at DRF +others again

[erikwrede]

@replygirl the only problem I see with nesting is the handling of schema directives. Maybe they need to be flatMapped in this case, but this should be easy to handle since only the outermost OR-extension will be respected. I'm open to any solutions, so just go with what works best for the next draft 😊

[codspeed-hq]

CodSpeed Performance Report

Merging #3315 will not alter performance

_{Comparing replygirl:or-permission (c275f12) with main (6c7b11f)}

Summary

✅ 11 untouched benchmarks

[codecov]

Codecov Report

Merging #3315 (c275f12) into main (6c7b11f) will decrease coverage by 1.82%.
The diff coverage is 93.00%.

Additional details and impacted files

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- Coverage   96.61%   94.80%   -1.82%     
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  Files         483      482       -1     
  Lines       30161    30187      +26     
  Branches     3726     3728       +2     
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- Hits        29140    28618     -522     
- Misses        832     1364     +532     
- Partials      189      205      +16