Merge branch 'master' into ab-fix-reorg-uncles-pagination

CHANGELOG.md

@@ -11,6 +11,7 @@
 - [#1806](https://github.com/poanetwork/blockscout/pull/1806) - verify contracts with a post request
 - [#1857](https://github.com/poanetwork/blockscout/pull/1857) - Re-implement Geth JS internal transaction tracer in Elixir
 - [#1859](https://github.com/poanetwork/blockscout/pull/1859) - feat: show raw transaction traces
+- [#1876](https://github.com/poanetwork/blockscout/pull/1876) - async calculate a count of blocks
 
 ### Fixes
 
@@ -29,6 +30,7 @@
 - [#1875](https://github.com/poanetwork/blockscout/pull/1875) - fix: resolve false positive constructor arguments 
 - [#1904](https://github.com/poanetwork/blockscout/pull/1904) - fix `BLOCK_COUNT_CACHE_TTL` env var type
 - [#1898](https://github.com/poanetwork/blockscout/pull/1898) - check if the constructor has arguments before verifying constructor arguments
+- [#1915](https://github.com/poanetwork/blockscout/pull/1915) - fallback to 2 latest evm versions
 
 ### Chore
 

apps/block_scout_web/lib/block_scout_web/controllers/chain_controller.ex

@@ -3,7 +3,7 @@ defmodule BlockScoutWeb.ChainController do
 
   alias BlockScoutWeb.ChainView
   alias Explorer.{Chain, PagingOptions, Repo}
-  alias Explorer.Chain.{Address, Block, BlockCountCache, Transaction}
+  alias Explorer.Chain.{Address, Block, Transaction}
   alias Explorer.Counters.AverageBlockTime
   alias Explorer.ExchangeRates.Token
   alias Explorer.Market
@@ -11,7 +11,7 @@ defmodule BlockScoutWeb.ChainController do
 
   def show(conn, _params) do
     transaction_estimated_count = Chain.transaction_estimated_count()
-    block_count = BlockCountCache.count()
+    block_count = Chain.block_estimated_count()
 
     exchange_rate = Market.get_exchange_rate(Explorer.coin()) || Token.null()
 

apps/explorer/config/config.exs

@@ -82,9 +82,6 @@ config :spandex_ecto, SpandexEcto.EctoLogger,
   tracer: Explorer.Tracer,
   otp_app: :explorer
 
-config :explorer, Explorer.Chain.BlockCountCache,
-  ttl: System.get_env("BLOCK_COUNT_CACHE_TTL") && String.to_integer(System.get_env("BLOCK_COUNT_CACHE_TTL"))
-
 # Import environment specific config. This must remain at the bottom
 # of this file so it overrides the configuration defined above.
 import_config "#{Mix.env()}.exs"

apps/explorer/lib/explorer/application.ex

@@ -29,7 +29,8 @@ defmodule Explorer.Application do
       Explorer.SmartContract.SolcDownloader,
       {Registry, keys: :duplicate, name: Registry.ChainEvents, id: Registry.ChainEvents},
       {Admin.Recovery, [[], [name: Admin.Recovery]]},
-      {TransactionCountCache, [[], []]}
+      {TransactionCountCache, [[], []]},
+      {BlockCountCache, []}
     ]
 
     children = base_children ++ configurable_children()
@@ -39,7 +40,6 @@ defmodule Explorer.Application do
     res = Supervisor.start_link(children, opts)
 
     BlockNumberCache.setup()
-    BlockCountCache.setup()
 
     res
   end

apps/explorer/lib/explorer/chain.ex

@@ -29,6 +29,7 @@ defmodule Explorer.Chain do
     Address.CurrentTokenBalance,
     Address.TokenBalance,
     Block,
+    BlockCountCache,
     BlockNumberCache,
     Data,
     DecompiledSmartContract,
@@ -1953,6 +1954,22 @@ defmodule Explorer.Chain do
     end
   end
 
+  @doc """
+  Estimated count of `t:Explorer.Chain.Block.t/0`.
+
+  Estimated count of consensus blocks.
+  """
+  @spec block_estimated_count() :: non_neg_integer()
+  def block_estimated_count do
+    cached_value = BlockCountCache.count()
+
+    if is_nil(cached_value) do
+      block_consensus_count()
+    else
+      cached_value
+    end
+  end
+
   @doc """
   `t:Explorer.Chain.InternalTransaction/0`s in `t:Explorer.Chain.Transaction.t/0` with `hash`.
 

apps/explorer/lib/explorer/chain/block_count_cache.ex

@@ -1,79 +1,129 @@
 defmodule Explorer.Chain.BlockCountCache do
   @moduledoc """
-  Cache for count consensus blocks.
+  Cache for block count.
   """
 
+  require Logger
+
+  use GenServer
+
   alias Explorer.Chain
 
-  @tab :block_count_cache
   # 10 minutes
   @cache_period 1_000 * 60 * 10
   @key "count"
-  @opts_key "opts"
+  @default_value nil
+  @name __MODULE__
 
-  @spec setup() :: :ok
-  def setup do
-    if :ets.whereis(@tab) == :undefined do
-      :ets.new(@tab, [
-        :set,
-        :named_table,
-        :public,
-        write_concurrency: true
-      ])
-    end
+  def start_link(params) do
+    name = params[:name] || @name
+    params_with_name = Keyword.put(params, :name, name)
 
-    setup_opts()
-    update_cache()
+    GenServer.start_link(__MODULE__, params_with_name, name: name)
+  end
 
-    :ok
+  def init(params) do
+    cache_period = period_from_env_var() || params[:cache_period] || @cache_period
+    current_value = params[:default_value] || @default_value
+    name = params[:name]
+
+    init_ets_table(name)
+
+    {:ok, {{cache_period, current_value, name}, nil}}
+  end
+
+  def count(process_name \\ __MODULE__) do
+    GenServer.call(process_name, :count)
   end
 
-  def count do
-    initial_cache = {_count, old_current_time} = cached_values()
+  def handle_call(:count, _, {{cache_period, default_value, name}, task}) do
+    {count, task} =
+      case cached_values(name) do
+        nil ->
+          {default_value, update_cache(task, name)}
 
-    {count, _current_time} =
-      if current_time() - old_current_time > cache_period() do
-        update_cache()
+        {cached_value, timestamp} ->
+          task =
+            if current_time() - timestamp > cache_period do
+              update_cache(task, name)
+            end
 
-        cached_values()
-      else
-        initial_cache
+          {cached_value, task}
       end
 
-    count
+    {:reply, count, {{cache_period, default_value, name}, task}}
+  end
+
+  def update_cache(nil, name) do
+    async_update_cache(name)
+  end
+
+  def update_cache(task, _) do
+    task
   end
 
-  defp update_cache do
+  def handle_cast({:update_cache, value}, {{cache_period, default_value, name}, _}) do
     current_time = current_time()
-    count = count_from_db()
-    tuple = {count, current_time}
+    tuple = {value, current_time}
 
-    :ets.insert(@tab, {@key, tuple})
+    table_name = table_name(name)
+
+    :ets.insert(table_name, {@key, tuple})
+
+    {:noreply, {{cache_period, default_value, name}, nil}}
   end
 
-  defp setup_opts do
-    cache_period = Application.get_env(:explorer, __MODULE__)[:ttl] || @cache_period
+  def handle_info({:DOWN, _, _, _, _}, {{cache_period, default_value, name}, _}) do
+    {:noreply, {{cache_period, default_value, name}, nil}}
+  end
 
-    :ets.insert(@tab, {@opts_key, cache_period})
+  def handle_info(_, {{cache_period, default_value, name}, _}) do
+    {:noreply, {{cache_period, default_value, name}, nil}}
   end
 
-  defp cached_values do
-    [{_, cached_values}] = :ets.lookup(@tab, @key)
+  # sobelow_skip ["DOS"]
+  defp table_name(name) do
+    name
+    |> Atom.to_string()
+    |> Macro.underscore()
+    |> String.to_atom()
+  end
 
-    cached_values
+  def async_update_cache(name) do
+    Task.async(fn ->
+      try do
+        result = Chain.fetch_count_consensus_block()
+
+        GenServer.cast(name, {:update_cache, result})
+      rescue
+        e ->
+          Logger.debug([
+            "Coudn't update block count test #{inspect(e)}"
+          ])
+      end
+    end)
   end
 
-  defp cache_period do
-    [{_, cache_period}] = :ets.lookup(@tab, @opts_key)
+  defp init_ets_table(name) do
+    table_name = table_name(name)
 
-    cache_period
+    if :ets.whereis(table_name) == :undefined do
+      :ets.new(table_name, [
+        :set,
+        :named_table,
+        :public,
+        write_concurrency: true
+      ])
+    end
   end
 
-  defp count_from_db do
-    Chain.fetch_count_consensus_block()
-  rescue
-    _e ->
-      0
+  defp cached_values(name) do
+    table_name = table_name(name)
+
+    case :ets.lookup(table_name, @key) do
+      [{_, cached_values}] -> cached_values
+      _ -> nil
+    end
   end
 
   defp current_time do
@@ -81,4 +131,17 @@ defmodule Explorer.Chain.BlockCountCache do
 
     DateTime.to_unix(utc_now, :millisecond)
   end
+
+  defp period_from_env_var do
+    case System.get_env("BLOCK_COUNT_CACHE_PERIOD") do
+      value when is_binary(value) ->
+        case Integer.parse(value) do
+          {integer, ""} -> integer * 1_000
+          _ -> nil
+        end
+
+      _ ->
+        nil
+    end
+  end
 end

apps/explorer/lib/explorer/smart_contract/verifier.ex

@@ -17,13 +17,29 @@ defmodule Explorer.SmartContract.Verifier do
     do: {:error, :contract_source_code}
 
   def evaluate_authenticity(address_hash, params) do
+    latest_evm_version = List.last(CodeCompiler.allowed_evm_versions())
+    evm_version = Map.get(params, "evm_version", latest_evm_version)
+
+    Enum.reduce([evm_version | previous_evm_versions(evm_version)], false, fn version, acc ->
+      case acc do
+        {:ok, _} = result ->
+          result
+
+        _ ->
+          cur_params = Map.put(params, "evm_version", version)
+          verify(address_hash, cur_params)
+      end
+    end)
+  end
+
+  defp verify(address_hash, params) do
     name = Map.fetch!(params, "name")
     contract_source_code = Map.fetch!(params, "contract_source_code")
     optimization = Map.fetch!(params, "optimization")
     compiler_version = Map.fetch!(params, "compiler_version")
     external_libraries = Map.get(params, "external_libraries", %{})
     constructor_arguments = Map.get(params, "constructor_arguments", "")
-    evm_version = Map.get(params, "evm_version", "byzantium")
+    evm_version = Map.get(params, "evm_version")
     optimization_runs = Map.get(params, "optimization_runs", 200)
 
     solc_output =
@@ -37,25 +53,7 @@ defmodule Explorer.SmartContract.Verifier do
         external_libs: external_libraries
       )
 
-    case compare_bytecodes(solc_output, address_hash, constructor_arguments) do
-      {:error, :generated_bytecode} ->
-        next_evm_version = next_evm_version(evm_version)
-
-        second_solc_output =
-          CodeCompiler.run(
-            name: name,
-            compiler_version: compiler_version,
-            code: contract_source_code,
-            optimize: optimization,
-            evm_version: next_evm_version,
-            external_libs: external_libraries
-          )
-
-        compare_bytecodes(second_solc_output, address_hash, constructor_arguments)
-
-      result ->
-        result
-    end
+    compare_bytecodes(solc_output, address_hash, constructor_arguments)
   end
 
   defp compare_bytecodes({:error, :name}, _, _), do: {:error, :name}
@@ -114,16 +112,21 @@ defmodule Explorer.SmartContract.Verifier do
     end
   end
 
-  def next_evm_version(current_evm_version) do
-    [prev_version, last_version] =
-      CodeCompiler.allowed_evm_versions()
-      |> Enum.reverse()
-      |> Enum.take(2)
+  def previous_evm_versions(current_evm_version) do
+    index = Enum.find_index(CodeCompiler.allowed_evm_versions(), fn el -> el == current_evm_version end)
+
+    cond do
+      index == 0 ->
+        []
 
-    if current_evm_version != last_version do
-      last_version
-    else
-      prev_version
+      index == 1 ->
+        [List.first(CodeCompiler.allowed_evm_versions())]
+
+      true ->
+        [
+          Enum.at(CodeCompiler.allowed_evm_versions(), index - 1),
+          Enum.at(CodeCompiler.allowed_evm_versions(), index - 2)
+        ]
     end
   end
 

apps/explorer/test/explorer/chain/block_count_cache_test.exs

@@ -3,43 +3,54 @@ defmodule Explorer.Chain.BlockCountCacheTest do
 
   alias Explorer.Chain.BlockCountCache
 
-  describe "count/0" do
-    test "return count" do
-      insert(:block, number: 1, consensus: true)
-      insert(:block, number: 2, consensus: true)
-      insert(:block, number: 3, consensus: false)
+  test "returns default transaction count" do
+    BlockCountCache.start_link(name: BlockTestCache)
 
-      BlockCountCache.setup()
+    result = BlockCountCache.count(BlockTestCache)
 
-      assert BlockCountCache.count() == 2
-    end
+    assert is_nil(result)
+  end
+
+  test "updates cache if initial value is zero" do
+    BlockCountCache.start_link(name: BlockTestCache)
+
+    insert(:block, consensus: true)
+    insert(:block, consensus: true)
+    insert(:block, consensus: false)
+
+    _result = BlockCountCache.count(BlockTestCache)
+
+    Process.sleep(1000)
+
+    updated_value = BlockCountCache.count(BlockTestCache)
+
+    assert updated_value == 2
+  end
 
-    test "invalidates cache if period did pass" do
-      insert(:block, number: 1, consensus: true)
+  test "does not update cache if cache period did not pass" do
+    BlockCountCache.start_link(name: BlockTestCache)
 
-      Application.put_env(:explorer, BlockCountCache, ttl: 2_00)
-      BlockCountCache.setup()
+    insert(:block, consensus: true)
+    insert(:block, consensus: true)
+    insert(:block, consensus: false)
 
-      assert BlockCountCache.count() == 1
+    _result = BlockCountCache.count(BlockTestCache)
 
-      insert(:block, number: 2, consensus: true)
+    Process.sleep(1000)
 
-      Process.sleep(2_000)
+    updated_value = BlockCountCache.count(BlockTestCache)
 
-      assert BlockCountCache.count() == 2
-    end
+    assert updated_value == 2
 
-    test "does not invalidate cache if period time did not pass" do
-      insert(:block, number: 1, consensus: true)
+    insert(:block, consensus: true)
+    insert(:block, consensus: true)
 
-      Application.put_env(:explorer, BlockCountCache, ttl: 2_00)
-      BlockCountCache.setup()
+    _updated_value = BlockCountCache.count(BlockTestCache)
 
-      assert BlockCountCache.count() == 1
+    Process.sleep(1000)
 
-      insert(:block, number: 2, consensus: true)
+    updated_value = BlockCountCache.count(BlockTestCache)
 
-      assert BlockCountCache.count() == 1
-    end
+    assert updated_value == 2
   end
 end