Add eth_blockNumber API endpoint to eth_rpc section

apps/block_scout_web/lib/block_scout_web/etherscan.ex

@@ -299,7 +299,7 @@ defmodule BlockScoutWeb.Etherscan do
 
   @block_eth_block_number_example_value %{
     "jsonrpc" => "2.0",
-    "result" => "767969",
+    "result" => "0xb33bf1",
     "id" => 1
   }
 

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

@@ -3,6 +3,7 @@ defmodule BlockScoutWeb.API.RPC.BlockView do
 
   alias BlockScoutWeb.API.RPC.{EthRPCView, RPCView}
   alias Explorer.Chain.{Hash, Wei}
+  alias Explorer.EthRPC, as: EthRPC
 
   def render("block_reward.json", %{block: block, reward: reward}) do
     reward_as_string =
@@ -23,7 +24,7 @@ defmodule BlockScoutWeb.API.RPC.BlockView do
   end
 
   def render("eth_block_number.json", %{number: number, id: id}) do
-    result = encode_quantity(number)
+    result = EthRPC.encode_quantity(number)
 
     EthRPCView.render("show.json", %{result: result, id: id})
   end
@@ -31,24 +32,4 @@ defmodule BlockScoutWeb.API.RPC.BlockView do
   def render("error.json", %{error: error}) do
     RPCView.render("error.json", error: error)
   end
-
-  defp encode_quantity(binary) when is_binary(binary) do
-    hex_binary = Base.encode16(binary, case: :lower)
-
-    result = String.replace_leading(hex_binary, "0", "")
-
-    final_result = if result == "", do: "0", else: result
-
-    "0x#{final_result}"
-  end
-
-  defp encode_quantity(value) when is_integer(value) do
-    value
-    |> :binary.encode_unsigned()
-    |> encode_quantity()
-  end
-
-  defp encode_quantity(value) when is_nil(value) do
-    nil
-  end
 end

apps/explorer/lib/explorer/eth_rpc.ex

@@ -6,9 +6,21 @@ defmodule Explorer.EthRPC do
   alias Ecto.Type, as: EctoType
   alias Explorer.{Chain, Repo}
   alias Explorer.Chain.{Block, Data, Hash, Hash.Address, Wei}
+  alias Explorer.Chain.Cache.BlockNumber
   alias Explorer.Etherscan.Logs
 
   @methods %{
+    "eth_blockNumber" => %{
+      action: :eth_block_number,
+      notes: nil,
+      example: """
+      {"id": 0, "jsonrpc": "2.0", "method": "eth_blockNumber", "params": []}
+      """,
+      params: [],
+      result: """
+      {"id": 0, "jsonrpc": "2.0", "result": "0xb3415c"}
+      """
+    },
     "eth_getBalance" => %{
       action: :eth_get_balance,
       notes: """
@@ -94,6 +106,16 @@ defmodule Explorer.EthRPC do
     end)
   end
 
+  def eth_block_number do
+    max_block_number = BlockNumber.get_max()
+
+    max_block_number_hex =
+      max_block_number
+      |> encode_quantity()
+
+    {:ok, max_block_number_hex}
+  end
+
   def eth_get_balance(address_param, block_param \\ nil) do
     with {:address, {:ok, address}} <- {:address, Chain.string_to_address_hash(address_param)},
          {:block, {:ok, block}} <- {:block, block_param(block_param)},
@@ -405,5 +427,25 @@ defmodule Explorer.EthRPC do
   defp block_param(nil), do: {:ok, :latest}
   defp block_param(_), do: :error
 
+  def encode_quantity(binary) when is_binary(binary) do
+    hex_binary = Base.encode16(binary, case: :lower)
+
+    result = String.replace_leading(hex_binary, "0", "")
+
+    final_result = if result == "", do: "0", else: result
+
+    "0x#{final_result}"
+  end
+
+  def encode_quantity(value) when is_integer(value) do
+    value
+    |> :binary.encode_unsigned()
+    |> encode_quantity()
+  end
+
+  def encode_quantity(value) when is_nil(value) do
+    nil
+  end
+
   def methods, do: @methods
 end