feat: add support for ON UPDATE and ON DELETE rules on belongs-to relationships from struct tags

[antipopp]

I was missing this feature from go-pg and wanted to add it to the codebase. AFAIK belongs-to is the only rel that would benefit from it, as it's the only one that generates a column on the DB. But I still don't know this repo as deeply as I want to, so feel free to correct me.

type User struct {
		ID   int    `bun:",pk,autoincrement"`
		Type string `bun:",pk"`
		Name string
}
type Deck struct {
		ID       int `bun:",pk,autoincrement"`
		UserID   int
		UserType string
		User     *User `bun:"rel:belongs-to,join:user_id=id,join:user_type=type,on_update:cascade,on_delete:set null"`
}

Also, should I tag the release for this?

[EllaFoxo]

Might be a good idea if we could have a test for this in db_test, similar to how foreign key violations are checked: db_test.go#L820

Love the change though, been missing this feature myself

[antipopp]

Might be a good idea if we could have a test for this in db_test, similar to how foreign key violations are checked: db_test.go#L820

Love the change though, been missing this feature myself

I've been thinking about the tests. What would a pattern look like? Create the table, insert entries, delete/update one and check that the FK has been updated?

also help me with commitlint lol

[EllaFoxo]

Yeah, I wouldn't imagine it has to be anything too complex. Try and force an update/delete and check for the intended result.

Re commit lint, it's expecting this one's message to be formatted correctly:
fix OnUpdate default string

You can do a rebase-edit to change the message - fix: change OnUpdate default string should be valid

[antipopp]

I've added the tests, tell me if there is anything else to fix

[EllaFoxo]

LGTM, I'm not a core contributor however so it'll have to wait for someone on the Uptrace team here to verify

[vmihailenco]

@antipopp thanks for the PR and @tinyfluffs thanks for reviewing 👍