absinthe-graphql/absinthe_relay

Use with Dataloader?

Un3qual opened this issue · 7 comments

Un3qual commented

How would I used Dataloader with absinthe_relay. Specifically, without dataloader I might return

Post
|> Connection.from_query(
  &(&1
  |> Query.join_user_and_group
  |> Query.preload_user_and_group
  |> Query.only_posts_in_users_groups(user)
  |> Repo.all
  ),
  pagination_args, 
  PostUtils.sort_to_order(pagination_args.sort),
  &PostUtils.order_to_where/3
)

But with dataloader I need to return a Dataloader.load_many or Dataloader.load, but if I do that, it will not be formatted as relay requires with nodes, edges, cursors, etc.

(note: Connection.from_query is modified from the one provided by absinthe_relay hence the extra arguments)

Un3qual commented

Whoops. Just found out about on_load.

Anber commented

Hi @Un3qual
How you solve this problem? Connection.from_query wants a query, but on_load has already loaded data.

Deleted user commented

Hi @Un3qual
I would be interested to know more about how you approached this too !

benwilson512 commented

There is not any way to use dataloader with relay from connection at this time, for the same reason that it wasn't possible with absinthe_ecto. The only way to generate sensible SQL is via a window fu function or lateral joins, neither of which are well supported by Ecto yet.

  • 👍3
Un3qual commented

@benwilson512 is right. I had to fork both dataloader and absinthe_relay and do some really hacky stuff and even then, I abandoned it because it's a major PITA.

  • 👍1
bruce commented

Is there an Ecto issue we can link to here for people? This is going to be a recurring question until it’s addressed there.

tmattio commented

@benwilson512 The PR implementing a WINDOW function has been merged in Ecto. Would it make sense to reopen this issue?

  • 👍13