Add ability to parse legacy genesis file

internal/cli/server/chains/chain.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/log"
 )
 
 type Chain struct {
@@ -59,5 +60,19 @@ func importChain(content []byte) (*Chain, error) {
 		return nil, err
 	}
 
+	if chain.Genesis == nil {
+		log.Info("Try reading as legacy genesis")
+		var genesis core.Genesis
+		if err := json.Unmarshal(content, &genesis); err != nil {
+			return nil, err
+		}
+		if genesis.Config != nil {
+			chain.Genesis = &genesis
+			chain.NetworkId = genesis.Config.ChainID.Uint64()
+		} else {
+			return nil, fmt.Errorf("unable to parse chain config")
+		}
+	}
+
 	return chain, nil
 }

internal/cli/server/chains/chain_test.go

@@ -18,6 +18,16 @@ func TestChain_ImportFromFile(t *testing.T) {
 			args:    args{filename: "test_files/chain_test.json"},
 			wantErr: false,
 		},
+		{
+			name:    "ImportFromFile correct legacy json file",
+			args:    args{filename: "test_files/chain_legacy_test.json"},
+			wantErr: false,
+		},
+		{
+			name:    "ImportFromFile wrong json file",
+			args:    args{filename: "test_files/wrong_chain.json"},
+			wantErr: true,
+		},
 		{
 			name:    "ImportFromFile nonexistent json file",
 			args:    args{filename: "test_files/chain_test_nonexistent.json"},

internal/cli/server/chains/test_files/wrong_chain.json

@@ -0,0 +1 @@
+{}