Update data object readone resolver for legacy scaffolding

[satrun77]

Module version 0.3
Silverstripe 4.8

The history tab for data objects displays the incorrect history. It displays the history of the first viewed object.

Steps to reproduce:

1- Data object with ModelAdmin.
2- Go to Model Admin
3- Click on any item.
4- View the history. The console output looks ok as follow

5- View another item.
6- The history tab display incorrect history or the same history as the previously viewed item

Fix

The fix is based on the code from https://github.com/silverstripe/silverstripe-cms/blob/4/_legacy/GraphQL/ReadOneResolver.php

[unclecheese]

Thanks for this. A bit of an oversight!

So I think the fix is correct, but we should move it to the admin module. The admin module takes on the responsibility of providing dual compatibility with graphql (it's what shims in the IDFilterType, for instance). We should extend that responsibility to update the READ_ONE resolver, as well, or at least provide a compatible option.

Suggested fix:

Take the resolver you've currently defined as an anonymous function, and move it to a static method in a class in the _legacy graphql directory in silverstripe-admin. Then, just reference the callable in here:

->setResolver([SomeClass::class, 'resolve'])

That way, other modules that may use readOne (thirdparty, e.g.) can have an easy fix when this happens and they won't have to duplicate any code.

Bonus points if we update the resolve function in the current readOne to warn, "Hey, it looks like you've got graphql 4 style filters and you're using the graphql 3 resolver."

[unclecheese]

As described in comment

[satrun77]

I have updated this PR and submitted a PR with admin module silverstripe/silverstripe-admin#1260

[unclecheese]

Awesome work. Thank you!

[satrun77]

@unclecheese I have submitted a PR for checking the resolver silverstripe/silverstripe-graphql#411