feat: Contract code on-demand fetcher (#9708)

* Contract code on-demand fetcher * Review comments #1 * Review comments #2: ignore addresses with nonce * Review comments 3: fix threshold calculation * Refine trigger_fetch function * Skip updating retries number in case of failed eth_getCode response
blockscout · May 10, 2024 · e271f25 · e271f25
1 parent f19d0be
commit e271f25
Show file tree

Hide file tree

Showing 48 changed files with 527 additions and 75 deletions.
diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_coin_balance_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_coin_balance_controller.ex
@@ -12,7 +12,7 @@ defmodule BlockScoutWeb.AddressCoinBalanceController do
   alias BlockScoutWeb.{AccessHelper, AddressCoinBalanceView, Controller}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.{Address, Wei}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   def index(conn, %{"address_id" => address_hash_string, "type" => "JSON"} = params) do

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_contract_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_contract_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.AddressContractController do
   alias BlockScoutWeb.AccessHelper
   alias Explorer.{Chain, Market}
   alias Explorer.SmartContract.Solidity.PublishHelper
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     address_options = [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_controller.ex
@@ -17,7 +17,8 @@ defmodule BlockScoutWeb.AddressController do
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address.Counters
   alias Explorer.Chain.{Address, Wei}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.ContractCode, as: ContractCodeOnDemand
   alias Phoenix.View
 
   def index(conn, %{"type" => "JSON"} = params) do
@@ -96,6 +97,8 @@ defmodule BlockScoutWeb.AddressController do
     with {:ok, address_hash} <- Chain.string_to_address_hash(address_hash_string),
          {:ok, address} <- Chain.hash_to_address(address_hash),
          {:ok, false} <- AccessHelper.restricted_access?(address_hash_string, params) do
+      ContractCodeOnDemand.trigger_fetch(address)
+
       render(
         conn,
         "_show_address_transactions.html",

diff --git a/...block_scout_web/lib/block_scout_web/controllers/address_decompiled_contract_controller.ex b/...block_scout_web/lib/block_scout_web/controllers/address_decompiled_contract_controller.ex
@@ -6,7 +6,7 @@ defmodule BlockScoutWeb.AddressDecompiledContractController do
 
   alias BlockScoutWeb.AccessHelper
   alias Explorer.{Chain, Market}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     with {:ok, address_hash} <- Chain.string_to_address_hash(address_hash_string),

diff --git a/...lock_scout_web/lib/block_scout_web/controllers/address_internal_transaction_controller.ex b/...lock_scout_web/lib/block_scout_web/controllers/address_internal_transaction_controller.ex
@@ -12,7 +12,7 @@ defmodule BlockScoutWeb.AddressInternalTransactionController do
   alias BlockScoutWeb.{AccessHelper, Controller, InternalTransactionView}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.{Address, Wei}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   def index(conn, %{"address_id" => address_hash_string, "type" => "JSON"} = params) do

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_logs_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_logs_controller.ex
@@ -12,7 +12,7 @@ defmodule BlockScoutWeb.AddressLogsController do
   alias BlockScoutWeb.{AccessHelper, AddressLogsView, Controller}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   use BlockScoutWeb, :controller

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_read_contract_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_read_contract_controller.ex
@@ -16,7 +16,7 @@ defmodule BlockScoutWeb.AddressReadContractController do
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
   alias Explorer.SmartContract.Reader
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     address_options = [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_read_proxy_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_read_proxy_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.AddressReadProxyController do
   alias BlockScoutWeb.AccessHelper
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     address_options = [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_token_balance_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_token_balance_controller.ex
@@ -4,7 +4,7 @@ defmodule BlockScoutWeb.AddressTokenBalanceController do
   alias BlockScoutWeb.AccessHelper
   alias Explorer.Chain
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.TokenBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenBalance, as: TokenBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     with true <- ajax?(conn),

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_token_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_token_controller.ex
@@ -10,7 +10,7 @@ defmodule BlockScoutWeb.AddressTokenController do
   alias BlockScoutWeb.{AccessHelper, AddressTokenView, Controller}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   def index(conn, %{"address_id" => address_hash_string, "type" => "JSON"} = params) do

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_token_transfer_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_token_transfer_controller.ex
@@ -7,7 +7,7 @@ defmodule BlockScoutWeb.AddressTokenTransferController do
   alias BlockScoutWeb.{AccessHelper, Controller, TransactionView}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.{Address, DenormalizationHelper}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   import BlockScoutWeb.Chain,

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_transaction_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_transaction_controller.ex
@@ -25,7 +25,7 @@ defmodule BlockScoutWeb.AddressTransactionController do
 
   alias Explorer.Chain.{DenormalizationHelper, Transaction, Wei}
 
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   alias Plug.Conn

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_validation_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_validation_controller.ex
@@ -13,7 +13,7 @@ defmodule BlockScoutWeb.AddressValidationController do
 
   alias BlockScoutWeb.{AccessHelper, BlockView, Controller}
   alias Explorer.{Chain, Market}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   def index(conn, %{"address_id" => address_hash_string, "type" => "JSON"} = params) do

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_withdrawal_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_withdrawal_controller.ex
@@ -16,7 +16,7 @@ defmodule BlockScoutWeb.AddressWithdrawalController do
 
   alias Explorer.Chain.Wei
 
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Phoenix.View
 
   def index(conn, %{"address_id" => address_hash_string, "type" => "JSON"} = params) do

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_write_contract_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_write_contract_controller.ex
@@ -15,7 +15,7 @@ defmodule BlockScoutWeb.AddressWriteContractController do
   alias BlockScoutWeb.AddressView
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     address_options = [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/address_write_proxy_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/address_write_proxy_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.AddressWriteProxyController do
   alias BlockScoutWeb.{AccessHelper, AddressView}
   alias Explorer.{Chain, Market}
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def index(conn, %{"address_id" => address_hash_string} = params) do
     address_options = [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/address_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/api/rpc/address_controller.ex
@@ -5,7 +5,7 @@ defmodule BlockScoutWeb.API.RPC.AddressController do
   alias Explorer.{Chain, Etherscan}
   alias Explorer.Chain.{Address, Wei}
   alias Explorer.Etherscan.{Addresses, Blocks}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   @api_true [api?: true]
 

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/address_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/address_controller.ex
@@ -28,7 +28,10 @@ defmodule BlockScoutWeb.API.V2.AddressController do
   alias Explorer.Chain.{Address, Hash, Transaction}
   alias Explorer.Chain.Address.Counters
   alias Explorer.Chain.Token.Instance
-  alias Indexer.Fetcher.{CoinBalanceOnDemand, TokenBalanceOnDemand}
+
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.ContractCode, as: ContractCodeOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenBalance, as: TokenBalanceOnDemand
 
   @transaction_necessity_by_association [
     necessity_by_association: %{
@@ -86,6 +89,8 @@ defmodule BlockScoutWeb.API.V2.AddressController do
            Address.maybe_preload_smart_contract_associations(address, @contract_address_preloads, @api_true) do
       CoinBalanceOnDemand.trigger_fetch(fully_preloaded_address)
 
+      ContractCodeOnDemand.trigger_fetch(address)
+
       conn
       |> put_status(200)
       |> render(:address, %{address: fully_preloaded_address |> maybe_preload_ens_to_address()})

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/token_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/token_controller.ex
@@ -5,7 +5,7 @@ defmodule BlockScoutWeb.API.V2.TokenController do
   alias BlockScoutWeb.API.V2.{AddressView, TransactionView}
   alias Explorer.{Chain, Repo}
   alias Explorer.Chain.{Address, BridgedToken, Token, Token.Instance}
-  alias Indexer.Fetcher.TokenTotalSupplyOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenTotalSupply, as: TokenTotalSupplyOnDemand
 
   import BlockScoutWeb.Chain,
     only: [

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/transaction_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/api/v2/transaction_controller.ex
@@ -34,7 +34,7 @@ defmodule BlockScoutWeb.API.V2.TransactionController do
   alias Explorer.Chain.PolygonZkevm.Reader, as: PolygonZkevmReader
   alias Explorer.Chain.ZkSync.Reader, as: ZkSyncReader
   alias Explorer.Counters.{FreshPendingTransactionsCounter, Transactions24hStats}
-  alias Indexer.Fetcher.FirstTraceOnDemand
+  alias Indexer.Fetcher.OnDemand.FirstTrace, as: FirstTraceOnDemand
 
   action_fallback(BlockScoutWeb.API.V2.FallbackController)
 

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/tokens/holder_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/tokens/holder_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.Tokens.HolderController do
   alias BlockScoutWeb.Tokens.HolderView
   alias Explorer.Chain
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.TokenTotalSupplyOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenTotalSupply, as: TokenTotalSupplyOnDemand
   alias Phoenix.View
 
   import BlockScoutWeb.Chain,

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/tokens/transfer_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/tokens/transfer_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.Tokens.TransferController do
   alias BlockScoutWeb.Tokens.TransferView
   alias Explorer.Chain
   alias Explorer.Chain.Address
-  alias Indexer.Fetcher.TokenTotalSupplyOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenTotalSupply, as: TokenTotalSupplyOnDemand
   alias Phoenix.View
 
   import BlockScoutWeb.Chain, only: [split_list_by_page: 1, paging_options: 1, next_page_params: 3]

diff --git a/apps/block_scout_web/lib/block_scout_web/controllers/transaction_raw_trace_controller.ex b/apps/block_scout_web/lib/block_scout_web/controllers/transaction_raw_trace_controller.ex
@@ -8,7 +8,7 @@ defmodule BlockScoutWeb.TransactionRawTraceController do
   alias BlockScoutWeb.{AccessHelper, TransactionController}
   alias EthereumJSONRPC
   alias Explorer.{Chain, Market}
-  alias Indexer.Fetcher.FirstTraceOnDemand
+  alias Indexer.Fetcher.OnDemand.FirstTrace, as: FirstTraceOnDemand
 
   def index(conn, %{"transaction_id" => hash_string} = params) do
     with {:ok, hash} <- Chain.string_to_transaction_hash(hash_string),

diff --git a/apps/block_scout_web/lib/block_scout_web/models/transaction_state_helper.ex b/apps/block_scout_web/lib/block_scout_web/models/transaction_state_helper.ex
@@ -10,7 +10,8 @@ defmodule BlockScoutWeb.Models.TransactionStateHelper do
   alias Explorer.{Chain, PagingOptions}
   alias Explorer.Chain.{Block, BlockNumberHelper, Transaction, Wei}
   alias Explorer.Chain.Cache.StateChanges
-  alias Indexer.Fetcher.{CoinBalanceOnDemand, TokenBalanceOnDemand}
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.TokenBalance, as: TokenBalanceOnDemand
 
   {:ok, burn_address_hash} = Chain.string_to_address_hash(burn_address_hash_string())
   @burn_address_hash burn_address_hash

diff --git a/apps/block_scout_web/lib/block_scout_web/notifier.ex b/apps/block_scout_web/lib/block_scout_web/notifier.ex
@@ -244,6 +244,10 @@ defmodule BlockScoutWeb.Notifier do
     Endpoint.broadcast("tokens:#{to_string(contract_address_hash)}", "token_total_supply", %{token: token})
   end
 
+  def handle_event({:chain_event, :fetched_bytecode, :on_demand, [address_hash, fetched_bytecode]}) do
+    Endpoint.broadcast("addresses:#{to_string(address_hash)}", "fetched_bytecode", %{fetched_bytecode: fetched_bytecode})
+  end
+
   def handle_event({:chain_event, :changed_bytecode, :on_demand, [address_hash]}) do
     Endpoint.broadcast("addresses:#{to_string(address_hash)}", "changed_bytecode", %{})
   end

diff --git a/apps/block_scout_web/lib/block_scout_web/realtime_event_handler.ex b/apps/block_scout_web/lib/block_scout_web/realtime_event_handler.ex
@@ -27,6 +27,7 @@ defmodule BlockScoutWeb.RealtimeEventHandler do
     Subscriber.to(:address_token_balances, :on_demand)
     Subscriber.to(:token_total_supply, :on_demand)
     Subscriber.to(:changed_bytecode, :on_demand)
+    Subscriber.to(:fetched_bytecode, :on_demand)
     Subscriber.to(:eth_bytecode_db_lookup_started, :on_demand)
     Subscriber.to(:zkevm_confirmed_batches, :realtime)
     # Does not come from the indexer

diff --git a/apps/block_scout_web/lib/block_scout_web/views/account/watchlist_view.ex b/apps/block_scout_web/lib/block_scout_web/views/account/watchlist_view.ex
@@ -4,7 +4,7 @@ defmodule BlockScoutWeb.Account.WatchlistView do
   alias BlockScoutWeb.Account.WatchlistAddressView
   alias Explorer.Account.WatchlistAddress
   alias Explorer.Market
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   def coin_balance_status(address) do
     CoinBalanceOnDemand.trigger_fetch(address)

diff --git a/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/address_controller_test.exs b/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/address_controller_test.exs
@@ -7,7 +7,7 @@ defmodule BlockScoutWeb.API.RPC.AddressControllerTest do
   alias Explorer.Chain
   alias Explorer.Chain.{Events.Subscriber, Transaction, Wei}
   alias Explorer.Counters.{AddressesCounter, AverageBlockTime}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
   alias Explorer.Repo
 
   setup :set_mox_global

diff --git a/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/eth_controller_test.exs b/apps/block_scout_web/test/block_scout_web/controllers/api/rpc/eth_controller_test.exs
@@ -3,7 +3,7 @@ defmodule BlockScoutWeb.API.RPC.EthControllerTest do
 
   alias Explorer.Counters.{AddressesCounter, AverageBlockTime}
   alias Explorer.Repo
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   @first_topic_hex_string_1 "0x7fcf532c15f0a6db0bd6d0e038bea71d30d808c7d98cb3bf7268a95bf5081b65"
   @first_topic_hex_string_2 "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"

diff --git a/apps/block_scout_web/test/block_scout_web/controllers/api/v2/address_controller_test.exs b/apps/block_scout_web/test/block_scout_web/controllers/api/v2/address_controller_test.exs
@@ -1885,24 +1885,24 @@ defmodule BlockScoutWeb.API.V2.AddressControllerTest do
     end
   end
 
-  describe "checks TokenBalanceOnDemand" do
+  describe "checks Indexer.Fetcher.OnDemand.TokenBalance" do
     setup do
       Supervisor.terminate_child(Explorer.Supervisor, Explorer.Chain.Cache.BlockNumber.child_id())
       Supervisor.restart_child(Explorer.Supervisor, Explorer.Chain.Cache.BlockNumber.child_id())
-      old_env = Application.get_env(:indexer, Indexer.Fetcher.TokenBalanceOnDemand)
+      old_env = Application.get_env(:indexer, Indexer.Fetcher.OnDemand.TokenBalance)
 
       Application.put_env(
         :indexer,
-        Indexer.Fetcher.TokenBalanceOnDemand,
+        Indexer.Fetcher.OnDemand.TokenBalance,
         Keyword.put(old_env, :fallback_threshold_in_blocks, 0)
       )
 
       on_exit(fn ->
-        Application.put_env(:indexer, Indexer.Fetcher.TokenBalanceOnDemand, old_env)
+        Application.put_env(:indexer, Indexer.Fetcher.OnDemand.TokenBalance, old_env)
       end)
     end
 
-    test "Indexer.Fetcher.TokenBalanceOnDemand broadcasts only updated balances", %{conn: conn} do
+    test "Indexer.Fetcher.OnDemand.TokenBalance broadcasts only updated balances", %{conn: conn} do
       address = insert(:address)
 
       ctbs_erc_20 =

diff --git a/apps/block_scout_web/test/block_scout_web/controllers/transaction_state_controller_test.exs b/apps/block_scout_web/test/block_scout_web/controllers/transaction_state_controller_test.exs
@@ -9,7 +9,7 @@ defmodule BlockScoutWeb.TransactionStateControllerTest do
   alias Explorer.Chain.Wei
   alias Indexer.Fetcher.CoinBalance.Catchup, as: CoinBalanceCatchup
   alias Explorer.Counters.{AddressesCounter, AverageBlockTime}
-  alias Indexer.Fetcher.CoinBalanceOnDemand
+  alias Indexer.Fetcher.OnDemand.CoinBalance, as: CoinBalanceOnDemand
 
   setup :set_mox_global
 

diff --git a/apps/explorer/lib/explorer/chain/address.ex b/apps/explorer/lib/explorer/chain/address.ex
@@ -9,7 +9,7 @@ defmodule Explorer.Chain.Address do
 
   alias Ecto.Association.NotLoaded
   alias Ecto.Changeset
-  alias Explorer.{Chain, PagingOptions}
+  alias Explorer.{Chain, PagingOptions, Repo}
 
   alias Explorer.Chain.{
     Address,
@@ -58,6 +58,8 @@ defmodule Explorer.Chain.Address do
              :names
            ]}
 
+  @timeout :timer.minutes(1)
+
   @typedoc """
    * `fetched_coin_balance` - The last fetched balance from Nethermind
    * `fetched_coin_balance_block_number` - the `t:Explorer.Chain.Block.t/0` `t:Explorer.Chain.Block.block_number/0` for
@@ -423,4 +425,18 @@ defmodule Explorer.Chain.Address do
 
     Chain.select_repo(options).exists?(query)
   end
+
+  @doc """
+  Sets contract_code for the given Explorer.Chain.Address
+  """
+  @spec set_contract_code(Hash.Address.t(), binary()) :: {non_neg_integer(), nil}
+  def set_contract_code(address_hash, contract_code) when not is_nil(address_hash) and is_binary(contract_code) do
+    now = DateTime.utc_now()
+
+    Repo.update_all(
+      from(address in __MODULE__, where: address.hash == ^address_hash),
+      [set: [contract_code: contract_code, updated_at: now]],
+      timeout: @timeout
+    )
+  end
 end
diff --git a/apps/explorer/lib/explorer/chain/address/coin_balance.ex b/apps/explorer/lib/explorer/chain/address/coin_balance.ex
@@ -148,4 +148,19 @@ defmodule Explorer.Chain.Address.CoinBalance do
     |> validate_required(@required_fields)
     |> unique_constraint(:block_number, name: :address_coin_balances_address_hash_block_number_index)
   end
+
+  @doc """
+  Query to fetch latest coin balance for the given address
+  """
+  @spec latest_coin_balance_query(Hash.Address.t(), non_neg_integer() | {:error, :empty_database}) :: Ecto.Query.t()
+  def latest_coin_balance_query(address_hash, stale_balance_window) do
+    from(
+      cb in __MODULE__,
+      where: cb.address_hash == ^address_hash,
+      where: cb.block_number >= ^stale_balance_window,
+      where: is_nil(cb.value_fetched_at),
+      order_by: [desc: :block_number],
+      limit: 1
+    )
+  end
 end