Data file is a collection of your catalog items available on your online store. This data needs to be converted into a format that allows the search engine to parse it and provide accurate results when a query is entered.
Line delimited JSON is the required format for data upload. The response from the engine is returned in JSON, and all examples in both data input and output will be using JSON.
Groupby uses the product schema as defined by the Google Cloud Retail Search reference found here:
If Groupby manages your ETL, this section does not apply to you. For customers migrating to Groupby Powered by Google currently managing their own ETL, please contact your customer services consultant to discuss a migration strategy.