Relay Modern API notes

These are areas we ran into where the docs are lacking:

• container:

  • setting default variable values (use @argumentDefinitions)
  • fields used in different fragments with different arguments lead to a clash, Relay no longer seems to automatically alias those fields like it did in Classic mode, so you need to manually alias those

• refetch container:

  • passing arguments for parameters defined with @argumentDefinitions (use `@arguments)

• pagination container:

  • setting the initial page size (use @argumentDefinitions to set default values, although that still means you may need to repeat the count constant in both JS code and the GraphQL fragment)
  • what the purpose of the various functions is (e.g. getFragmentVariables vs getVariables etc)

• mutations:

  • For connections, still need to provide a mutation ‘config’, but it’s no longer used to append/prepend a new record to the prop and used to re-render, only for how to update the store, I think? Instead we now have to use the imperative API to trigger a UI update.