feat: set a ping_interval from config, defaulting to 300 seconds

CHANGELOG.md

@@ -6,6 +6,7 @@
 - [#1696](https://github.com/poanetwork/blockscout/pull/1696) - full-text search by tokens
 - [#1742](https://github.com/poanetwork/blockscout/pull/1742) - Support RSK
 - [#1777](https://github.com/poanetwork/blockscout/pull/1777) - show ERC-20 token transfer info on transaction page
+- [#1770](https://github.com/poanetwork/blockscout/pull/1770) - set a websocket keepalive from config
 
 ### Fixes
 

apps/ethereum_jsonrpc/lib/ethereum_jsonrpc/web_socket/web_socket_client.ex

@@ -50,7 +50,9 @@ defmodule EthereumJSONRPC.WebSocket.WebSocketClient do
 
   @impl WebSocket
   # only allow secure WSS
-  def start_link(["wss://" <> _ = url, gen_fsm_options]) when is_list(gen_fsm_options) do
+  def start_link(["wss://" <> _ = url, websocket_opts, gen_fsm_options]) when is_list(gen_fsm_options) do
+    keepalive = websocket_opts[:keepalive]
+
     fsm_name =
       case Keyword.fetch(gen_fsm_options, :name) do
         {:ok, name} when is_atom(name) -> {:local, name}
@@ -68,6 +70,7 @@ defmodule EthereumJSONRPC.WebSocket.WebSocketClient do
       __MODULE__,
       url,
       ssl_verify: :verify_peer,
+      keepalive: keepalive,
       socket_opts: [
         cacerts: :certifi.cacerts(),
         depth: 99,
@@ -78,7 +81,9 @@ defmodule EthereumJSONRPC.WebSocket.WebSocketClient do
     )
   end
 
-  def start_link(["ws://" <> _ = url, gen_fsm_options]) when is_list(gen_fsm_options) do
+  def start_link(["ws://" <> _ = url, websocket_opts, gen_fsm_options]) when is_list(gen_fsm_options) do
+    keepalive = websocket_opts[:keepalive]
+
     fsm_name =
       case Keyword.fetch(gen_fsm_options, :name) do
         {:ok, name} when is_atom(name) -> {:local, name}
@@ -90,7 +95,7 @@ defmodule EthereumJSONRPC.WebSocket.WebSocketClient do
       url,
       __MODULE__,
       url,
-      []
+      keepalive: keepalive
     )
   end
 

apps/ethereum_jsonrpc/test/ethereum_jsonrpc/web_socket/web_socket_client_test.exs

@@ -89,7 +89,7 @@ defmodule EthereumJSONRPC.WebSocket.WebSocketClientTest do
 
       port = :ranch.get_port(EthereumJSONRPC.WebSocket.Cowboy)
 
-      pid = start_supervised!({WebSocketClient, ["ws://localhost:#{port}/websocket", []]})
+      pid = start_supervised!({WebSocketClient, ["ws://localhost:#{port}/websocket", [keepalive: :timer.hours(1)], []]})
 
       %{pid: pid, port: port}
     end

apps/ethereum_jsonrpc/test/support/ethereum_jsonrpc/web_socket/case/geth.ex

@@ -8,7 +8,7 @@ defmodule EthereumJSONRPC.WebSocket.Case.Geth do
   def setup do
     url = "wss://mainnet.infura.io/ws/8lTvJTKmHPCHazkneJsY"
     web_socket_module = EthereumJSONRPC.WebSocket.WebSocketClient
-    web_socket = start_supervised!({web_socket_module, [url, []]})
+    web_socket = start_supervised!({web_socket_module, [url, [keepalive: :timer.minutes(10)], []]})
 
     %{
       block_interval: 25_000,

apps/ethereum_jsonrpc/test/support/ethereum_jsonrpc/web_socket/case/mox.ex

@@ -19,7 +19,7 @@ defmodule EthereumJSONRPC.WebSocket.Case.Mox do
       Supervisor.child_spec(
         %{
           id: web_socket_module,
-          start: {web_socket_module, :start_link, arguments}
+          start: {web_socket_module, :start_link, [arguments]}
         },
         []
       )
@@ -29,7 +29,7 @@ defmodule EthereumJSONRPC.WebSocket.Case.Mox do
     end)
 
     url = "wss://example.com/ws"
-    web_socket = start_supervised!({web_socket_module, [url]})
+    web_socket = start_supervised!({web_socket_module, [url, [keepalive: :timer.minutes(10)]]})
 
     %{
       block_interval: @block_interval,

apps/ethereum_jsonrpc/test/support/ethereum_jsonrpc/web_socket/case/parity.ex

@@ -8,7 +8,7 @@ defmodule EthereumJSONRPC.WebSocket.Case.Parity do
   def setup do
     url = "ws://3.85.253.242:8546"
     web_socket_module = EthereumJSONRPC.WebSocket.WebSocketClient
-    web_socket = start_supervised!({web_socket_module, [url, []]})
+    web_socket = start_supervised!({web_socket_module, [url, [keepalive: :timer.minutes(10)], []]})
 
     %{
       block_interval: 5_000,

apps/indexer/README.md

@@ -104,6 +104,10 @@ Memory usage is checked once per minute.  If the soft-limit is reached, the shri
 
 If all queues are at their minimum size, then no more memory can be reclaimed and an error will be logged.
 
+## Websocket Keepalive
+
+This defaults to 150 seconds, but it can be set via adding a configuration to `subscribe_named_arguments` in the appropriate config file (indexer/config/<env>/<variant>.exs) called `:keep_alive`. The value is an integer representing milliseconds.
+
 ## Testing
 
 ### Parity

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

@@ -22,12 +22,14 @@ defmodule Indexer.Block.Realtime.Supervisor do
           transport_options = %EthereumJSONRPC.WebSocket{transport_options | web_socket_options: web_socket_options}
           %EthereumJSONRPC.WebSocket{url: url, web_socket: web_socket_module} = transport_options
 
+          keepalive = Keyword.get(subscribe_named_arguments, :keep_alive, :timer.seconds(150))
+
           block_fetcher_subscribe_named_arguments =
             put_in(subscribe_named_arguments[:transport_options], transport_options)
 
           [
             {Task.Supervisor, name: Indexer.Block.Realtime.TaskSupervisor},
-            {web_socket_module, [url, [name: web_socket]]},
+            {web_socket_module, [url, [keepalive: keepalive], [name: web_socket]]},
             {Indexer.Block.Realtime.Fetcher,
              [
                %{block_fetcher: block_fetcher, subscribe_named_arguments: block_fetcher_subscribe_named_arguments},