Merge branch 'master' into ab-timestamp-block-overview

CHANGELOG.md

@@ -14,6 +14,7 @@
  - [#1743](https://github.com/poanetwork/blockscout/pull/1743) - sort decompiled smart contracts in lexicographical order
  - [#1756](https://github.com/poanetwork/blockscout/pull/1756) - add today's token balance from the previous value
  - [#1769](https://github.com/poanetwork/blockscout/pull/1769) - add timestamp to block overview
+ - [#1778](https://github.com/poanetwork/blockscout/pull/1778) - Make websocket optional for realtime fetcher
 
 ### Chore
 

apps/indexer/config/prod/parity.exs

@@ -17,7 +17,7 @@ config :indexer,
     variant: EthereumJSONRPC.Parity
   ],
   subscribe_named_arguments: [
-    transport: EthereumJSONRPC.WebSocket,
+    transport: System.get_env("ETHEREUM_JSONRPC_WS_URL") && EthereumJSONRPC.WebSocket,
     transport_options: [
       web_socket: EthereumJSONRPC.WebSocket.WebSocketClient,
       url: System.get_env("ETHEREUM_JSONRPC_WS_URL")

apps/indexer/config/prod/rsk.exs

@@ -19,7 +19,7 @@ config :indexer,
     variant: EthereumJSONRPC.RSK
   ],
   subscribe_named_arguments: [
-    transport: EthereumJSONRPC.WebSocket,
+    transport: System.get_env("ETHEREUM_JSONRPC_WS_URL") && EthereumJSONRPC.WebSocket,
     transport_options: [
       web_socket: EthereumJSONRPC.WebSocket.WebSocketClient,
       url: System.get_env("ETHEREUM_JSONRPC_WS_URL")

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

@@ -57,8 +57,7 @@ defmodule Indexer.Block.Realtime.Fetcher do
   end
 
   @impl GenServer
-  def init(%{block_fetcher: %Block.Fetcher{} = block_fetcher, subscribe_named_arguments: subscribe_named_arguments})
+  def init(%{block_fetcher: %Block.Fetcher{} = block_fetcher, subscribe_named_arguments: subscribe_named_arguments}) do
-      when is_list(subscribe_named_arguments) do
     Logger.metadata(fetcher: :block_realtime)
 
     {:ok, %__MODULE__{block_fetcher: %Block.Fetcher{block_fetcher | broadcast: :realtime, callback_module: __MODULE__}},
@@ -66,17 +65,9 @@ defmodule Indexer.Block.Realtime.Fetcher do
   end
 
   @impl GenServer
-  def handle_continue({:init, subscribe_named_arguments}, %__MODULE__{subscription: nil} = state)
+  def handle_continue({:init, subscribe_named_arguments}, %__MODULE__{subscription: nil} = state) do
-      when is_list(subscribe_named_arguments) do
+    timer = schedule_polling()
-    case EthereumJSONRPC.subscribe("newHeads", subscribe_named_arguments) do
+    {:noreply, %__MODULE__{state | timer: timer} |> subscribe_to_new_heads(subscribe_named_arguments)}
-      {:ok, subscription} ->
-        timer = schedule_polling()
-
-        {:noreply, %__MODULE__{state | subscription: subscription, timer: timer}}
-
-      {:error, reason} ->
-        {:stop, reason, state}
-    end
   end
 
   @impl GenServer
@@ -141,6 +132,20 @@ defmodule Indexer.Block.Realtime.Fetcher do
      }}
   end
 
+  defp subscribe_to_new_heads(%__MODULE__{subscription: nil} = state, subscribe_named_arguments)
+       when is_list(subscribe_named_arguments) do
+    case EthereumJSONRPC.subscribe("newHeads", subscribe_named_arguments) do
+      {:ok, subscription} ->
+        %__MODULE__{state | subscription: subscription}
+
+      {:error, reason} ->
+        Logger.debug(fn -> ["Could not connect to websocket: ", reason, ". Continuing with polling."] end)
+        state
+    end
+  end
+
+  defp subscribe_to_new_heads(state, _), do: state
+
   defp new_max_number(number, nil), do: number
 
   defp new_max_number(number, max_number_seen), do: max(number, max_number_seen)

apps/indexer/lib/indexer/block/realtime/supervisor.ex

@@ -34,6 +34,16 @@ defmodule Indexer.Block.Realtime.Supervisor do
                [name: Indexer.Block.Realtime.Fetcher]
              ]}
           ]
+
+        _ ->
+          [
+            {Task.Supervisor, name: Indexer.Block.Realtime.TaskSupervisor},
+            {Indexer.Block.Realtime.Fetcher,
+             [
+               %{block_fetcher: block_fetcher, subscribe_named_arguments: nil},
+               [name: Indexer.Block.Realtime.Fetcher]
+             ]}
+          ]
       end
 
     Supervisor.init(children, strategy: :rest_for_one)