Make polling interval configurable

ethers/providers/jsonrpc/subscriptions.nim

@@ -99,7 +99,8 @@ type
   PollingSubscriptions = ref object of JsonRpcSubscriptions
 
 proc new*(_: type JsonRpcSubscriptions,
-          client: RpcHttpClient): JsonRpcSubscriptions =
+          client: RpcHttpClient,
+          pollingInterval = 4.seconds): JsonRpcSubscriptions =
 
   let subscriptions = PollingSubscriptions(client: client)
 
@@ -113,7 +114,7 @@ proc new*(_: type JsonRpcSubscriptions,
       while true:
         for id in toSeq subscriptions.callbacks.keys:
           await poll(id)
-        await sleepAsync(1.seconds)
+        await sleepAsync(pollingInterval)
     except CancelledError:
       raise
 

testmodule/providers/jsonrpc/testJsonRpcSubscriptions.nim

@@ -49,6 +49,7 @@ suite "HTTP polling subscriptions":
   setup:
     client = newRpcHttpClient()
     await client.connect("http://localhost:8545")
-    subscriptions = JsonRpcSubscriptions.new(client)
+    subscriptions = JsonRpcSubscriptions.new(client,
+                                             pollingInterval = 100.millis)
 
   subscriptionTests(subscriptions, client)