chore(rln-relay): remove websocket from OnchainGroupManager (#2364)

* chore(rln-relay): remove websocket from OnchainGroupManager

* fix: swap ws for http

apps/chat2/config_chat2.nim

@@ -252,8 +252,8 @@ type
       name: "rln-relay-id-commitment-key" }: string
 
     rlnRelayEthClientAddress* {.
-      desc: "WebSocket address of an Ethereum testnet client e.g., ws://localhost:8540/",
-      defaultValue: "ws://localhost:8540/"
+      desc: "WebSocket address of an Ethereum testnet client e.g., http://localhost:8540/",
+      defaultValue: "http://localhost:8540/"
       name: "rln-relay-eth-client-address" }: string
 
     rlnRelayEthContractAddress* {.

apps/wakunode2/external_config.nim

@@ -61,8 +61,8 @@ type
       name: "rln-relay-cred-path" }: string
 
     rlnRelayEthClientAddress* {.
-      desc: "WebSocket address of an Ethereum testnet client e.g., ws://localhost:8540/",
-      defaultValue: "ws://localhost:8540/",
+      desc: "WebSocket address of an Ethereum testnet client e.g., http://localhost:8540/",
+      defaultValue: "http://localhost:8540/",
       name: "rln-relay-eth-client-address" }: string
 
     rlnRelayEthContractAddress* {.

tests/waku_rln_relay/test_rln_group_manager_onchain.nim

@@ -232,9 +232,9 @@ suite "Onchain group manager":
 
     try:
       await manager.startGroupSync()
-    except ValueError:
+    except CatchableError:
       assert true
-    except Exception, CatchableError:
+    except Exception:
       assert false, "exception raised when calling startGroupSync: " & getCurrentExceptionMsg()
 
     await manager.stop()
@@ -330,9 +330,9 @@ suite "Onchain group manager":
 
     try:
       await manager.register(dummyCommitment)
-    except ValueError:
+    except CatchableError:
       assert true
-    except Exception, CatchableError:
+    except Exception:
       assert false, "exception raised: " & getCurrentExceptionMsg()
 
     await manager.stop()
@@ -399,9 +399,9 @@ suite "Onchain group manager":
 
     try:
       await manager.withdraw(idSecretHash)
-    except ValueError:
+    except CatchableError:
       assert true
-    except Exception, CatchableError:
+    except Exception:
       assert false, "exception raised: " & getCurrentExceptionMsg()
 
     await manager.stop()
@@ -627,7 +627,7 @@ suite "Onchain group manager":
     await manager.stop()
 
   asyncTest "isReady should return false if ethRpc is none":
-    var manager = await setup()
+    let manager = await setup()
     await manager.init()
 
     manager.ethRpc = none(Web3)
@@ -644,7 +644,7 @@ suite "Onchain group manager":
     await manager.stop()
 
   asyncTest "isReady should return false if lastSeenBlockHead > lastProcessed":
-    var manager = await setup()
+    let manager = await setup()
     await manager.init()
 
     var isReady = true
@@ -659,14 +659,13 @@ suite "Onchain group manager":
     await manager.stop()
 
   asyncTest "isReady should return true if ethRpc is ready":
-    var manager = await setup()
+    let manager = await setup()
     await manager.init()
     # node can only be ready after group sync is done
     try:
       await manager.startGroupSync()
     except Exception, CatchableError:
       assert false, "exception raised when calling startGroupSync: " & getCurrentExceptionMsg()
-    
     var isReady = false
     try:
       isReady = await manager.isReady()

waku/waku_rln_relay/constants.nim

@@ -18,7 +18,7 @@ const
   MembershipFee* = 1000000000000000.u256
   #  the current implementation of the rln lib supports a circuit for Merkle tree with depth 20
   MerkleTreeDepth* = 20
-  EthClient* = "ws://127.0.0.1:8540"
+  EthClient* = "http://127.0.0.1:8540"
 
 const
   # the size of poseidon hash output in bits

waku/waku_rln_relay/group_manager/on_chain/group_manager.nim

@@ -74,13 +74,17 @@ type
     # in event of a reorg. we store 5 in the buffer. Maybe need to revisit this,
     # because the average reorg depth is 1 to 2 blocks.
     validRootBuffer*: Deque[MerkleNode]
+    # interval loop to shut down gracefully
+    blockFetchingActive*: bool
 
 const DefaultKeyStorePath* = "rlnKeystore.json"
 const DefaultKeyStorePassword* = "password"
 
+const DefaultBlockPollRate* = 6.seconds
+
 template initializedGuard(g: OnchainGroupManager): untyped =
   if not g.initialized:
-    raise newException(ValueError, "OnchainGroupManager is not initialized")
+    raise newException(CatchableError, "OnchainGroupManager is not initialized")
 
 
 proc setMetadata*(g: OnchainGroupManager): RlnRelayResult[void] =
@@ -316,12 +320,15 @@ proc handleRemovedEvents(g: OnchainGroupManager, blockTable: BlockTable):
 
 proc getAndHandleEvents(g: OnchainGroupManager,
                         fromBlock: BlockNumber,
-                        toBlock: BlockNumber): Future[void] {.async: (raises: [Exception]).} =
+                        toBlock: BlockNumber): Future[bool] {.async: (raises: [Exception]).} =
   initializedGuard(g)
-
   let blockTable = await g.getBlockTable(fromBlock, toBlock)
-  await g.handleEvents(blockTable)
-  await g.handleRemovedEvents(blockTable)
+  try:
+    await g.handleEvents(blockTable)
+    await g.handleRemovedEvents(blockTable)
+  except CatchableError:
+    error "failed to handle events", error=getCurrentExceptionMsg()
+    raise newException(ValueError, "failed to handle events")
 
   g.latestProcessedBlock = toBlock
   let metadataSetRes = g.setMetadata()
@@ -331,31 +338,48 @@ proc getAndHandleEvents(g: OnchainGroupManager,
   else:
     trace "rln metadata persisted", blockNumber = g.latestProcessedBlock
   
-proc getNewHeadCallback(g: OnchainGroupManager): BlockHeaderHandler =
-  proc newHeadCallback(blockheader: BlockHeader) {.gcsafe.} =
-      let latestBlock = BlockNumber(blockheader.number)
-      trace "block received", blockNumber = latestBlock
-      # get logs from the last block
-      try:
-        # inc by 1 to prevent double processing
-        let fromBlock = g.latestProcessedBlock + 1
-        asyncSpawn g.getAndHandleEvents(fromBlock, latestBlock)
-      except CatchableError:
-        warn "failed to handle log: ", error=getCurrentExceptionMsg()
-  return newHeadCallback
+  return true
 
-proc newHeadErrCallback(error: CatchableError) =
-  warn "failed to get new head", error=error.msg
+proc runInInterval(g: OnchainGroupManager, cb: proc, interval: Duration): void =
+  g.blockFetchingActive = false
+
+  proc runIntervalLoop() {.async, gcsafe.} =
+    g.blockFetchingActive = true
+
+    while g.blockFetchingActive:
+      var retCb: bool
+      retryWrapper(retCb, RetryStrategy.new(), "Failed to run the interval loop"):
+        await cb()
+      await sleepAsync(interval)
+
+  asyncSpawn runIntervalLoop()
+  
+
+proc getNewBlockCallback(g: OnchainGroupManager): proc =
+  let ethRpc = g.ethRpc.get()
+  proc wrappedCb(): Future[bool] {.async, gcsafe.} =
+    var latestBlock: BlockNumber
+    retryWrapper(latestBlock, RetryStrategy.new(), "Failed to get the latest block number"):
+      cast[BlockNumber](await ethRpc.provider.eth_blockNumber())
+    
+    if latestBlock <= g.latestProcessedBlock:
+      return
+    # get logs from the last block
+    # inc by 1 to prevent double processing
+    let fromBlock = g.latestProcessedBlock + 1
+    var handleBlockRes: bool
+    retryWrapper(handleBlockRes, RetryStrategy.new(), "Failed to handle new block"):
+      await g.getAndHandleEvents(fromBlock, latestBlock)
+    return true
+  return wrappedCb
 
 proc startListeningToEvents(g: OnchainGroupManager):
                             Future[void] {.async: (raises: [Exception]).} =
   initializedGuard(g)
 
   let ethRpc = g.ethRpc.get()
-  let newHeadCallback = g.getNewHeadCallback()
-  var blockHeaderSub: Subscription
-  retryWrapper(blockHeaderSub, RetryStrategy.new(), "Failed to subscribe to block headers"):
-    await ethRpc.subscribeForBlockHeaders(newHeadCallback, newHeadErrCallback)
+  let newBlockCallback = g.getNewBlockCallback()
+  g.runInInterval(newBlockCallback, DefaultBlockPollRate)
 
 proc startOnchainSync(g: OnchainGroupManager):
                       Future[void] {.async: (raises: [Exception]).} =
@@ -385,7 +409,9 @@ proc startOnchainSync(g: OnchainGroupManager):
 
       let toBlock = min(fromBlock + BlockNumber(blockChunkSize), currentLatestBlock)
       debug "fetching events", fromBlock = fromBlock, toBlock = toBlock
-      await g.getAndHandleEvents(fromBlock, toBlock)
+      var handleBlockRes: bool
+      retryWrapper(handleBlockRes, RetryStrategy.new(), "Failed to handle old blocks"): 
+        await g.getAndHandleEvents(fromBlock, toBlock)
       fromBlock = toBlock + 1
 
   except CatchableError:
@@ -523,13 +549,15 @@ method init*(g: OnchainGroupManager): Future[void] {.async.} =
       error "failed to restart group sync", error = getCurrentExceptionMsg()
 
   ethRpc.ondisconnect = proc() =
-    asyncCheck onDisconnect()
+    asyncSpawn onDisconnect()
     
 
   waku_rln_number_registered_memberships.set(int64(g.rlnInstance.leavesSet()))
   g.initialized = true
 
-method stop*(g: OnchainGroupManager): Future[void] {.async.} =
+method stop*(g: OnchainGroupManager): Future[void] {.async,gcsafe.} =
+  g.blockFetchingActive = false
+  
   if g.ethRpc.isSome():
     g.ethRpc.get().ondisconnect = nil
     await g.ethRpc.get().close()

waku/waku_rln_relay/group_manager/on_chain/retry_wrapper.nim

@@ -21,12 +21,15 @@ template retryWrapper*(res: auto,
                        body: untyped): auto =
   var retryCount = retryStrategy.retryCount
   var shouldRetry = retryStrategy.shouldRetry
+  var exceptionMessage = ""
+
   while shouldRetry and retryCount > 0:
     try:
       res = body
       shouldRetry = false
     except:
       retryCount -= 1
+      exceptionMessage = getCurrentExceptionMsg()
       await sleepAsync(retryStrategy.retryDelay)
   if shouldRetry:
-    raise newException(CatchableError, errStr & ": " & $getCurrentExceptionMsg())
+    raise newException(CatchableError, errStr & ": " & exceptionMessage)