Add API v2 response for zkEVM batch page (partially)

apps/block_scout_web/lib/block_scout_web/api_router.ex

@@ -209,6 +209,10 @@ defmodule BlockScoutWeb.ApiRouter do
       get("/", V2.WithdrawalController, :withdrawals_list)
       get("/counters", V2.WithdrawalController, :withdrawals_counters)
     end
+
+    scope "/zkevm" do
+      get("/batches/:batch_number", V2.ZkevmController, :batch)
+    end
   end
 
   scope "/v1", as: :api_v1 do

apps/block_scout_web/lib/block_scout_web/controllers/api/v2/zkevm_controller.ex

@@ -0,0 +1,26 @@
+defmodule BlockScoutWeb.API.V2.ZkevmController do
+  use BlockScoutWeb, :controller
+
+  alias Explorer.Chain
+
+  action_fallback(BlockScoutWeb.API.V2.FallbackController)
+
+  @batch_necessity_by_association %{
+    :sequence_transaction => :optional,
+    :verify_transaction => :optional,
+    :l2_transactions => :required
+  }
+
+  def batch(conn, %{"batch_number" => batch_number} = _params) do
+    {:ok, batch} =
+      Chain.zkevm_batch(
+        batch_number,
+        necessity_by_association: @batch_necessity_by_association,
+        api?: true
+      )
+
+    conn
+    |> put_status(200)
+    |> render(:zkevm_batch, %{batch: batch})
+  end
+end

apps/block_scout_web/lib/block_scout_web/views/api/v2/zkevm_view.ex

@@ -0,0 +1,22 @@
+defmodule BlockScoutWeb.API.V2.ZkevmView do
+  use BlockScoutWeb, :view
+
+  def render("zkevm_batch.json", %{batch: batch}) do
+    %{
+      "number" => batch.number,
+      "status" => batch_status(batch),
+      "timestamp" => batch.timestamp
+    }
+  end
+
+  defp batch_status(batch) do
+    sequence_id = Map.get(batch, :sequence_id)
+    verify_id = Map.get(batch, :verify_id)
+
+    cond do
+      is_nil(sequence_id) && is_nil(verify_id) -> "Unfinalized"
+      !is_nil(sequence_id) && is_nil(verify_id) -> "L1 Sequence Confirmed"
+      !is_nil(verify_id) -> "Finalized"
+    end
+  end
+end

apps/explorer/lib/explorer/chain.ex

@@ -64,7 +64,8 @@ defmodule Explorer.Chain do
     TokenTransfer,
     Transaction,
     Wei,
-    Withdrawal
+    Withdrawal,
+    ZkevmTxnBatch
   }
 
   alias Explorer.Chain.Block.{EmissionReward, Reward}
@@ -6389,6 +6390,18 @@ defmodule Explorer.Chain do
           )
       }
     )
+
+  def zkevm_batch(number, options \\ []) when is_list(options) do
+    necessity_by_association = Keyword.get(options, :necessity_by_association, %{})
+
+    ZkevmTxnBatch
+    |> where(number: ^number)
+    |> join_associations(necessity_by_association)
+    |> select_repo(options).one()
+    |> case do
+      nil -> {:error, :not_found}
+      batch -> {:ok, batch}
+    end
   end
 
   @spec verified_contracts_top(non_neg_integer()) :: [Hash.Address.t()]