Add NetworkId flag to InitConfig

src/Nethermind/Nethermind.Api/IInitConfig.cs

@@ -39,6 +39,9 @@ public interface IInitConfig : IConfig
     [ConfigItem(Description = "The hash of the genesis block. If not specified, the genesis block validity is not checked which is useful in the case of ad hoc test/private networks.", DefaultValue = "null")]
     string? GenesisHash { get; set; }
 
+    [ConfigItem(Description = "The network id. If not specified, taken from the chain spec file.", DefaultValue = "null", HiddenFromDocs = true)]
+    ulong? NetworkId { get; set; }
+
     [ConfigItem(Description = "The path to the static nodes file.", DefaultValue = "static-nodes.json")]
     string StaticNodesPath { get; set; }
 

src/Nethermind/Nethermind.Api/InitConfig.cs

@@ -18,6 +18,7 @@ public class InitConfig : IInitConfig
         public string BaseDbPath { get; set; } = "db";
         public string LogFileName { get; set; } = "log.txt";
         public string? GenesisHash { get; set; }
+        public ulong? NetworkId { get; set; }
         public string StaticNodesPath { get; set; } = "static-nodes.json";
         public string TrustedNodesPath { get; set; } = "trusted-nodes.json";
         public string? KzgSetupPath { get; set; } = null;

src/Nethermind/Nethermind.Runner/Ethereum/Api/ApiBuilder.cs

@@ -72,6 +72,13 @@ private ChainSpec LoadChainSpec(IJsonSerializer ethereumJsonSerializer)
 
         var loader = new ChainSpecFileLoader(ethereumJsonSerializer, _logger);
         ChainSpec chainSpec = loader.LoadEmbeddedOrFromFile(_initConfig.ChainSpecPath);
+
+        //overwriting NetworkId which is useful for some devnets (like bloatnet)
+        if (_initConfig.NetworkId is not null)
+        {
+            chainSpec.NetworkId = (ulong)_initConfig.NetworkId;
+        }
+
         return chainSpec;
     }