Hey team, I got several other questions when trying to implement corresponding GraphQL logic in

datahub-graphql-core

module according to the "DataHub GraphQL Core" readme page: 1. Looks like the ReadMe needs some update? I could not easily find what the doc told me to do, like

resources/gms.graphql

,

DataLoaders

,

Mappers

and

DataFetchers

2. Looks like the

SearchableEntityType

is deprecated. Should the new LoadableType extend SearchableEntityType? If no, what’s the alternative? 3. I am a little confused about

RestliEntityClient

and

JavaEntityClient

Looks like, they both finally call

EntityService -> EbeanAspectDao -> DB

The difference is

RestliEntityClient

send a Restli request and the Restli server calles

EntityService

But

JavaEntityClient

call

EntityService

directly? If I would like to introduce a new entity, looks like I do not need to change them? 4. Looks like Mappers and DataFetchers are not needed now since batchLoad() return GraphQL object?

1. Yes, the readme needs an update. Some details have changed in the past couple months. We will prioritize the work on our side 2. We've moved to using

SearchAcrossEntitiesResolver

for handling cross-entity search in one place. You'll need to update this to add your entity to search! SearchableEntityType was previously used when we had search for each entity type separately. 3. Both of these clients do what you mentioned - eventually call the DB. One does so indirectly, over the wire. The other is "in process". This is really just to make sharing the API across different components of DataHub easier (mcl consumer, gms, etc). You should not need to change this to add a new entity. Simply use the

batchGetV2

API to fetch aspects for your new entity, as detailed inside of

DatasetType.java

4. Mappers are optional. Inside of your NewEntityType.java, you'll need to map the GMS objects to the auto-generated GraphQL equivalent. We tend to define mappers to do this part! You're correct that you should not need to add a DataFetcher if you've defined a Type. You simply need to register the Type class in

GmsGraphQLEngine.java

Great! Thanks for explaining!

Ah, think it was fixed with this PR: https://github.com/datahub-project/datahub/pull/4400

Sorry for the delay folks- yes this should be addressed as mentioned