Source file `dal_services.ml`

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(*****************************************************************************)
(*                                                                           *)
(* Open Source License                                                       *)
(* Copyright (c) 2022 Nomadic Labs <contact@nomadic-labs.com>                *)
(*                                                                           *)
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(*****************************************************************************)

open Alpha_context

let assert_dal_feature_enabled ctxt =
  let open Constants in
  let Parametric.{dal = {feature_enable; _}; _} = parametric ctxt in
  error_unless
    Compare.Bool.(feature_enable = true)
    Dal_errors.Dal_feature_disabled

let shards ctxt ~level =
  let open Lwt_result_syntax in
  let open Dal.Attestation in
  assert_dal_feature_enabled ctxt >>?= fun () ->
  let level = Level.from_raw ctxt level in
  let pkh_from_tenderbake_slot slot =
    Stake_distribution.slot_owner ctxt level slot
    >|=? fun (ctxt, consensus_key) -> (ctxt, consensus_key.delegate)
  in
  (* We do not cache this committee. This function being used by RPCs
     to know the DAL committee at some particular level. *)
  let* committee =
    Dal.Attestation.compute_committee ctxt pkh_from_tenderbake_slot
  in
  Signature.Public_key_hash.Map.bindings committee.pkh_to_shards |> return