Indexer.CoinBalance.Fetcher bytes and integer instead of string in

buffers

```elixir
  test "memory" do
    CoinBalance.Supervisor.Case.start_supervised!(json_rpc_named_arguments: [])
    pid = Process.whereis(CoinBalance.Fetcher)

    Stream.repeatedly(fn -> %{address_hash: address_hash(), block_number: block_number()} end)
    |> Enum.take(100)
    |> CoinBalance.Fetcher.async_fetch_balances()

    Process.info(pid, :memory) |> elem(1) |> IO.inspect(label: "BEFORE GC")

    :erlang.garbage_collect(pid)

    Process.info(pid, :memory) |> elem(1) |> IO.inspect(label: "AFTER GC")
  end
```

| Balances | Garbage Collection | String (bytes) | Bytes and Integer (bytes) | Bytes / String (%) |
|----------|--------------------|----------------|---------------------------|--------------------|
| 100      | Before             | 55,244         | 34,548                    | 62.54              |
| 100      | After              | 21,764         | 13,860                    | 63.68              |
| 1,000    | Before             | 601,972        | 372,444                   | 61.87              |
| 1,000    | After              | 230,596        | 142,924                   | 61.98              |
| 10,000   | Before             | 4,119,668      | 2,546,460                 | 61.81              |
| 10,000   | After              | 1,574,172      | 973,260                   | 61.83              |
| 100,000  | Before             | 16,586,644     | 11,519,724                | 69.45              |
| 100,000  | After              | 16,583,636     | 11,516,716                | 69.45              |

apps/indexer/lib/indexer/block/fetcher.ex

@@ -5,7 +5,7 @@ defmodule Indexer.Block.Fetcher do
 
   require Logger
 
-  alias Explorer.Chain.{Block, Import}
+  alias Explorer.Chain.{Address, Block, Import}
   alias Indexer.{CoinBalance, AddressExtraction, Token, TokenTransfers}
   alias Indexer.Address.{CoinBalances, TokenBalances}
   alias Indexer.Block.Fetcher.Receipts
@@ -164,7 +164,7 @@ defmodule Indexer.Block.Fetcher do
         address_hash_to_fetched_balance_block_number: address_hash_to_block_number
       }) do
     addresses
-    |> Enum.map(fn address_hash ->
+    |> Enum.map(fn %Address{hash: address_hash} ->
       block_number = Map.fetch!(address_hash_to_block_number, to_string(address_hash))
       %{address_hash: address_hash, block_number: block_number}
     end)

apps/indexer/lib/indexer/coin_balance/fetcher.ex

@@ -29,9 +29,9 @@ defmodule Indexer.CoinBalance.Fetcher do
           %{required(:address_hash) => Hash.Address.t(), required(:block_number) => Block.block_number()}
         ]) :: :ok
   def async_fetch_balances(balance_fields) when is_list(balance_fields) do
-    params_list = Enum.map(balance_fields, &balance_fields_to_params/1)
+    entries = Enum.map(balance_fields, &entry/1)
 
-    BufferedTask.buffer(__MODULE__, params_list)
+    BufferedTask.buffer(__MODULE__, entries)
   end
 
   @doc false
@@ -57,7 +57,7 @@ defmodule Indexer.CoinBalance.Fetcher do
     {:ok, final} =
       Chain.stream_unfetched_balances(initial, fn address_fields, acc ->
         address_fields
-        |> balance_fields_to_params()
+        |> entry()
         |> reducer.(acc)
       end)
 
@@ -65,14 +65,17 @@ defmodule Indexer.CoinBalance.Fetcher do
   end
 
   @impl BufferedTask
-  def run(params_list, _retries, json_rpc_named_arguments) do
+  def run(entries, _retries, json_rpc_named_arguments) do
     # the same address may be used more than once in the same block, but we only want one `Balance` for a given
     # `{address, block}`, so take unique params only
-    unique_params_list = Enum.uniq(params_list)
+    unique_entries = Enum.uniq(entries)
 
-    Logger.debug(fn -> "fetching #{length(unique_params_list)} balances" end)
+    Logger.debug(fn -> "fetching #{length(unique_entries)} balances" end)
 
-    case EthereumJSONRPC.fetch_balances(unique_params_list, json_rpc_named_arguments) do
+    unique_entries
+    |> Enum.map(&entry_to_params/1)
+    |> EthereumJSONRPC.fetch_balances(json_rpc_named_arguments)
+    |> case do
       {:ok, balances_params} ->
         value_fetched_at = DateTime.utc_now()
 
@@ -89,16 +92,21 @@ defmodule Indexer.CoinBalance.Fetcher do
         :ok
 
       {:error, reason} ->
-        Logger.debug(fn -> "failed to fetch #{length(unique_params_list)} balances, #{inspect(reason)}" end)
-        {:retry, unique_params_list}
+        Logger.debug(fn -> "failed to fetch #{length(unique_entries)} balances, #{inspect(reason)}" end)
+        {:retry, unique_entries}
     end
   end
 
-  defp balance_fields_to_params(%{address_hash: address_hash, block_number: block_number})
+  defp entry_to_params(%{address_hash_bytes: address_hash_bytes, block_number: block_number})
        when is_integer(block_number) do
+    {:ok, address_hash} = Hash.Address.cast(address_hash_bytes)
     %{block_quantity: integer_to_quantity(block_number), hash_data: to_string(address_hash)}
   end
 
+  defp entry(%{address_hash: %Hash{bytes: address_hash_bytes}, block_number: block_number}) do
+    %{address_hash_bytes: address_hash_bytes, block_number: block_number}
+  end
+
   # We want to record all historical balances for an address, but have the address itself have balance from the
   # `Balance` with the greatest block_number for that address.
   def balances_params_to_address_params(balances_params) do

apps/indexer/test/indexer/coin_balance/fetcher_test.exs

@@ -251,9 +251,10 @@ defmodule Indexer.CoinBalance.FetcherTest do
         end)
       end
 
-      params_list = Enum.map(block_quantities, &%{block_quantity: &1, hash_data: hash_data})
+      {:ok, %Hash{bytes: address_hash_bytes}} = Hash.Address.cast(hash_data)
+      entries = Enum.map(block_quantities, &%{address_hash_bytes: address_hash_bytes, block_number: quantity_to_integer(&1)})
 
-      case CoinBalance.Fetcher.run(params_list, 0, json_rpc_named_arguments) do
+      case CoinBalance.Fetcher.run(entries, 0, json_rpc_named_arguments) do
         :ok ->
           balances = Repo.all(from(balance in Address.CoinBalance, where: balance.address_hash == ^hash_data))
 
@@ -283,12 +284,14 @@ defmodule Indexer.CoinBalance.FetcherTest do
         other ->
           # not all nodes behind the `https://mainnet.infura.io` pool are fully-synced.  Node that aren't fully-synced
           # won't have historical address balances.
-          assert {:retry, ^params_list} = other
+          assert {:retry, ^entries} = other
       end
     end
 
-    test "duplicate params retry unique params", %{json_rpc_named_arguments: json_rpc_named_arguments} do
-      hash_data = "0x000000000000000000000000000000000"
+    test "duplicate entries retry unique entries", %{json_rpc_named_arguments: json_rpc_named_arguments} do
+      hash_data = "0x0000000000000000000000000000000000000000"
+
+      {:ok, %Hash{bytes: bytes}} = Hash.Address.cast(hash_data)
 
       if json_rpc_named_arguments[:transport] == EthereumJSONRPC.Mox do
         EthereumJSONRPC.Mox
@@ -298,15 +301,15 @@ defmodule Indexer.CoinBalance.FetcherTest do
       end
 
       assert CoinBalance.Fetcher.run(
-               [%{block_quantity: "0x1", hash_data: hash_data}, %{block_quantity: "0x1", hash_data: hash_data}],
+               [%{address_hash_bytes: bytes, block_number: 1}, %{address_hash_bytes: bytes, block_number: 1}],
                0,
                json_rpc_named_arguments
              ) ==
                {:retry,
                 [
                   %{
-                    block_quantity: "0x1",
-                    hash_data: "0x000000000000000000000000000000000"
+                    address_hash_bytes: <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>>,
+                    block_number: 1
                   }
                 ]}
     end