As a Magento Developer, 

I would like GrraphQL to return product ratings and reviews data in a highly performant and scalable way by building the feature in the Catalog Storefront app

So that

Merchants who install Catalog Storefront app can continue to show the product ratings and reviews in a performant way.

Acceptance Criteria

• Catalog Storefront only support READ operations
• Review creation will continue to use the existing GraphQL endpoint
• Storefront app has the following data for ratings & reviews
  • Review Count
  • Reviews
    • Pagination support

Tech details:

• The following GQL Sceham should be exposed to Export API/SF API app/code/Magento/ReviewGraphQl/etc/schema.graphqls
  • Only Review/Rating for READ operations should be handled by Export API/SF API
  • Do not expose Review Count in Export API
  • Review Count must be calculated (aggregation Query to ES index) during request to SF API
• Export API should have a separate feed for Product Reviews
• Pagination should be available on SF API side

For Grooming:
as an output we should receive read-to-use :

• et_schema (for Export API)
• proto schema with services to obtain review/rating data