add eth_BlockNumber

apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/block_controller.ex

@@ -23,4 +23,10 @@ defmodule BlockScoutWeb.API.RPC.BlockController do
         render(conn, :error, error: "Block does not exist")
     end
   end
+
+  def eth_block_number(conn, _params) do
+    max_block_number = Chain.fetch_max_block_number()
+
+    render(conn, :eth_block_number, number: max_block_number)
+  end
 end

apps/block_scout_web/lib/block_scout_web/views/api/rpc/block_view.ex

@@ -22,6 +22,14 @@ defmodule BlockScoutWeb.API.RPC.BlockView do
     RPCView.render("show.json", data: data)
   end
 
+  def render("eth_block_number.json", %{number: number}) do
+    data = %{
+      "blockNumber" => to_string(number)
+    }
+
+    RPCView.render("show.json", data: data)
+  end
+
   def render("error.json", %{error: error}) do
     RPCView.render("error.json", error: error)
   end

apps/explorer/lib/explorer/chain.ex

@@ -1059,6 +1059,22 @@ defmodule Explorer.Chain do
     end
   end
 
+  @spec fetch_max_block_number() :: non_neg_integer
+  def fetch_max_block_number do
+    query =
+      from(block in Block,
+        select: max(block.number),
+        where: block.consensus == true
+      )
+
+    result = Repo.one!(query)
+
+    case result do
+      nil -> 0
+      _ -> result
+    end
+  end
+
   @spec fetch_count_consensus_block() :: non_neg_integer
   def fetch_count_consensus_block do
     query =