ash-project/ash

Many to many and on match destroy in `manage_relationship`

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#859 opened on Jan 30, 2024

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 (2 comments) (1 reaction) (0 assignees)Elixir (389 forks)batch import
buggood first issue

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Description

I think on_match: :destroy in manage_relationship is incorrect for many_to_many.

Right now it destroys a join resource. Instead it should destroy both a join and a destination like other types of relationships do.

If one wants to destroy only a join resource then they should use :unrelate.

Destroy is implemented correctly for on_missing where :destroy destroys both and :unrelate only join one. (Though there is a mistake in documentation that states that it is possible to pass [:join, :keys] with a long form.) That's the only other case with support for :destroy so it is strange that they are inconsistent.

Contributor guide

Research direction
Find the `manage relationship` function in the codebase and examine how `on match` options are handled for `many to many` relationships. Specifically, modify the logic so that `:destroy` destroys both the join resource and the destination, and use `:unrelate` for destroying only the join. Ensure consistency with the `on missing` behavior.
Tech stack
elixir
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
ElixirGit
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65