custom network support in nrpc (#3148)

* custom network support in  for devnet testing

* use single config

* use joinPath

Author: advaita-saha

nrpc/config.nim

@@ -73,11 +73,14 @@ type
       abbr: "i"
       name: "network" }: string
 
-    customNetwork {.
-      desc: "Use custom genesis block for private Ethereum Network (as /path/to/genesis.json)"
-      defaultValueDesc: ""
-      abbr: "c"
-      name: "custom-network" }: Option[NetworkParams]
+    customNetworkFolder* {.
+        desc: "Use custom config for private Ethereum Network (as /path/to/metadata)"
+        longDesc:
+          "Path to a folder containing custom network configuration files\n" &
+          "such as genesis.json, config.yaml, etc.\n" &
+          "config.yaml is the configuration file for the CL client"
+        defaultValue: ""
+        name: "custom-network" .}: string
 
     networkId* {.
       ignore # this field is not processed by confutils
@@ -187,8 +190,12 @@ proc makeConfig*(cmdLine = commandLineParams()): NRpcConf
 
   var networkId = result.getNetworkId()
 
-  if result.customNetwork.isSome:
-    result.networkParams = result.customNetwork.get()
+  if result.customNetworkFolder.len > 0:
+    var networkParams = NetworkParams()
+    if not loadNetworkParams(result.customNetworkFolder.joinPath("genesis.json"), networkParams):
+      error "Failed to load customNetwork", path=result.customNetworkFolder
+      quit QuitFailure
+    result.networkParams = networkParams
     if networkId.isNone:
       # WARNING: networkId and chainId are two distinct things
       # they usage should not be mixed in other places.
@@ -204,7 +211,7 @@ proc makeConfig*(cmdLine = commandLineParams()): NRpcConf
 
   result.networkId = networkId.get()
 
-  if result.customNetwork.isNone:
+  if result.customNetworkFolder.len == 0:
     result.networkParams = networkParams(result.networkId)
 
 

nrpc/nrpc.nim

@@ -8,7 +8,7 @@
 # those terms.
 
 import
-  std/sequtils,
+  std/[sequtils, os],
   chronicles,
   ../execution_chain/constants,
   ../execution_chain/core/chain,
@@ -80,8 +80,14 @@ template loadNetworkConfig(conf: NRpcConf): (RuntimeConfig, uint64, uint64) =
   elif conf.networkId == HoodiNet:
     (getMetadataForNetwork("hoodi").cfg, 0'u64, 0'u64)
   else:
-    error "Unsupported network", network = conf.networkId
-    quit(QuitFailure)
+    notice "Loading custom network, assuming post-merge"
+    if conf.customNetworkFolder.len == 0:
+      error "Custom network file not provided"
+      quit(QuitFailure)
+    let (cfg, unloaded) = readRuntimeConfig(conf.customNetworkFolder.joinPath("config.yaml"))
+    debug "Fields unknown", unloaded = unloaded
+    (cfg, 0'u64, 0'u64)
+
 
 # Slot Finding Mechanism
 # First it sets the initial lower bound to `firstSlotAfterMerge` + number of blocks after Era1