Allow the deposit contract deployment block to be specified as a numb…

…er (needed for Medalla)

beacon_chain/beacon_node.nim

@@ -165,14 +165,28 @@ proc init*(T: type BeaconNode,
         fatal "Deposit contract deployment block not specified"
         quit 1
 
+      let web3 = web3Provider(conf.web3Url)
+      let deployedAtAsHash =
+        if conf.depositContractDeployedAt.get.startsWith "0x":
+          try: BlockHash.fromHex conf.depositContractDeployedAt.get
+          except ValueError:
+            fatal "Invalid hex value specified for deposit-contract-block"
+            quit 1
+        else:
+          let blockNum = try: parseBiggestUInt conf.depositContractDeployedAt.get
+                         except ValueError:
+                           fatal "Invalid nummeric value for deposit-contract-block"
+                           quit 1
+          await getEth1BlockHash(conf.web3Url, blockId blockNum)
+
       # TODO Could move this to a separate "GenesisMonitor" process or task
       #      that would do only this - see Paul's proposal for this.
       mainchainMonitor = MainchainMonitor.init(
         conf.runtimePreset,
-        web3Provider(conf.web3Url),
+        web3,
         conf.depositContractAddress.get,
-        Eth1Data(block_hash: conf.depositContractDeployedAt.get.asEth2Digest,
-                 deposit_count: 0))
+        Eth1Data(block_hash: deployedAtAsHash.asEth2Digest, deposit_count: 0))
+
       mainchainMonitor.start()
 
       genesisState = await mainchainMonitor.waitGenesis()
@@ -1097,7 +1111,7 @@ programMain:
       startTime = uint64(times.toUnix(times.getTime()) + config.genesisOffset)
       outGenesis = config.outputGenesis.string
       eth1Hash = if config.web3Url.len == 0: eth1BlockHash
-                 else: waitFor getLatestEth1BlockHash(config.web3Url)
+                 else: (waitFor getEth1BlockHash(config.web3Url, blockId("latest"))).asEth2Digest
     var
       initialState = initialize_beacon_state_from_eth1(
         defaultRuntimePreset, eth1Hash, startTime, deposits, {skipBlsValidation})

beacon_chain/conf.nim

@@ -68,8 +68,8 @@ type
       name: "deposit-contract" }: Option[Eth1Address]
 
     depositContractDeployedAt* {.
-      desc: "The Eth1 block hash where the deposit contract has been deployed"
-      name: "deposit-contract-block" }: Option[Eth1BlockHash]
+      desc: "The Eth1 block number or hash where the deposit contract has been deployed"
+      name: "deposit-contract-block" }: Option[string]
 
     nonInteractive* {.
       desc: "Do not display interative prompts. Quit on missing configuration"

beacon_chain/mainchain_monitor.nim

@@ -798,11 +798,11 @@ proc start(m: MainchainMonitor, delayBeforeStart: Duration) =
 proc start*(m: MainchainMonitor) {.inline.} =
   m.start(0.seconds)
 
-proc getLatestEth1BlockHash*(url: string): Future[Eth2Digest] {.async.} =
+proc getEth1BlockHash*(url: string, blockId: RtBlockIdentifier): Future[BlockHash] {.async.} =
   let web3 = await newWeb3(url)
   try:
-    let blk = await web3.provider.eth_getBlockByNumber("latest", false)
-    return Eth2Digest(data: array[32, byte](blk.hash))
+    let blk = await web3.provider.eth_getBlockByNumber(blockId, false)
+    return blk.hash
   finally:
     await web3.close()
 

beacon_chain/network_metadata.nim

@@ -38,7 +38,7 @@ type
       bootstrapNodes*: seq[string]
 
       depositContractAddress*: Eth1Address
-      depositContractDeployedAt*: Eth1BlockHash
+      depositContractDeployedAt*: string
 
       # Please note that we are using `string` here because SSZ.decode
       # is not currently usable at compile time and we want to load the
@@ -110,9 +110,9 @@ proc loadEth2NetworkMetadata*(path: string): Eth2NetworkMetadata
         default(Eth1Address)
 
       depositContractBlock = if fileExists(depositContractBlockPath):
-        Eth1BlockHash.fromHex readFile(depositContractBlockPath).strip
+        readFile(depositContractBlockPath).strip
       else:
-        default(Eth1BlockHash)
+        ""
 
       bootstrapNodes = if fileExists(bootstrapNodesPath):
         readFile(bootstrapNodesPath).splitLines()
@@ -145,7 +145,7 @@ const
       # TODO The values below are just placeholders for now
       bootstrapNodes: @[],
       depositContractAddress: Eth1Address.fromHex "0x1234567890123456789012345678901234567890",
-      depositContractDeployedAt: Eth1BlockHash.fromHex "0x73056f16a59bf70abad5b4365438e8a7d646aa0d7f56d22c3d9e4c6000d8e176",
+      depositContractDeployedAt: "0",
       genesisData: "")
   else:
     Eth2NetworkMetadata(