WebhooksManager#recreate_webhooks! should creates webhooks

[tomriley]

What this PR does

#recreate_webhooks! doesn't seem to attempt to create webhooks after destroying them. This patch fixes that.

I have also removed the suggestion of including manual registration of mandatory webhooks from the generator template. Shopify graphql API documentation states that these shouldn't be registered manually via the API and instead need be set up on the partner dashboard (in App Settings). From the docs:

"You don't create webhook subscriptions to mandatory webhooks. Instead, you configure mandatory webhooks in your Partner Dashboard as part of your app setup."

To avoid errors, existing users should remove the three mandatory webhooks from their ShopifyApp.configuration.webhooks.

Reviewer's guide to testing

Mandatory webhook configuration should be removed before testing on a real app.

Things to focus on

1. Is Shopify documentation correct? Are all these manually webhook API subscriptions just being ignored? Why are the subscription not failing? So many questions...

Checklist

Before submitting the PR, please consider if any of the following are needed:

• Update CHANGELOG.md if the changes would impact users
• Update README.md, if appropriate.
• Update any relevant pages in /docs, if necessary
• For security fixes, the Disclosure Policy must be followed.

[tomriley]

I have signed the CLA!

[tomriley]

Okay, I better understand the issue now - the config is required for ShopifyApp::WebhooksController to hand of handling of a mandatory webhook to ShopifyAPI::Webhooks::Registry. I still think this is a bug in shopify_app and mandatory webhooks should be handled as a special case. They have to be statically configured through the partner dashboard and not per-install. Treating them the same as regular webhooks seems to be the problem.

I will look at updating ShopifyApp::WebhooksController...

[nelsonwittwer]

Thanks for your help finding the solution here. I stumbled across this same solution with #1743 while trying to track down another issue. Totally agree that mandatory webhooks are goofy here within the app gem. I'll get that working before I merge in that PR. Closing this and consolidating with #1743

[nelsonwittwer]

Friction with mandatory topics has been addressed here - Shopify/shopify-api-ruby#1237

Thanks for your help identifying this problem!