Add genesis generate command

gno.land/Makefile

@@ -6,22 +6,24 @@ help:
 rundep=go run -modfile ../misc/devdeps/go.mod
 
 .PHONY: build
-build: build.gnoland build.gnokey build.gnoweb build.gnofaucet build.gnotxsync
+build: build.gnoland build.gnokey build.gnoweb build.gnofaucet build.gnotxsync build.genesis
 
 build.gnoland:;    go build -o build/gnoland   ./cmd/gnoland
 build.gnoweb:;     go build -o build/gnoweb    ./cmd/gnoweb
 build.gnofaucet:;  go build -o build/gnofaucet ./cmd/gnofaucet
 build.gnokey:;     go build -o build/gnokey    ./cmd/gnokey
 build.gnotxsync:;  go build -o build/gnotxsync  ./cmd/gnotxsync
+build.genesis:;  go build -o build/genesis  ./cmd/genesis
 
 .PHONY: install
-install: install.gnoland install.gnoweb install.gnofaucet install.gnokey install.gnotxsync
+install: install.gnoland install.gnoweb install.gnofaucet install.gnokey install.gnotxsync install.genesis
 
 install.gnoland:;    go install ./cmd/gnoland
 install.gnoweb:;     go install ./cmd/gnoweb
 install.gnofaucet:;  go install ./cmd/gnofaucet
 install.gnokey:;     go install ./cmd/gnokey
 install.gnotxsync:;  go install ./cmd/gnotxsync
+install.genesis:;  go install ./cmd/genesis
 
 .PHONY: fclean
 fclean: clean

gno.land/cmd/genesis/generate.go

@@ -0,0 +1,149 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/gnolang/gno/tm2/pkg/bft/types"
+	"github.com/gnolang/gno/tm2/pkg/commands"
+)
+
+var defaultChainID = "dev"
+
+type generateCfg struct {
+	outputPath        string
+	chainID           string
+	genesisTime       int64
+	blockMaxTxBytes   int64
+	blockMaxDataBytes int64
+	blockMaxGas       int64
+	blockTimeIota     int64
+}
+
+// newGenerateCmd creates the genesis generate subcommand
+func newGenerateCmd(io *commands.IO) *commands.Command {
+	cfg := &generateCfg{}
+
+	return commands.NewCommand(
+		commands.Metadata{
+			Name:       "generate",
+			ShortUsage: "generate [flags]",
+			LongHelp:   "Generates a node's genesis.json",
+		},
+		cfg,
+		func(_ context.Context, args []string) error {
+			return execGenerate(cfg, io)
+		},
+	)
+}
+
+func (c *generateCfg) RegisterFlags(fs *flag.FlagSet) {
+	fs.StringVar(
+		&c.outputPath,
+		"output-path",
+		"./genesis.json",
+		"the output path for the genesis.json",
+	)
+
+	fs.Int64Var(
+		&c.genesisTime,
+		"genesis-time",
+		time.Now().Unix(),
+		"the genesis creation time. Defaults to current time",
+	)
+
+	fs.StringVar(
+		&c.chainID,
+		"chain-id",
+		defaultChainID,
+		"the ID of the chain",
+	)
+
+	fs.Int64Var(
+		&c.blockMaxTxBytes,
+		"block-max-tx-bytes",
+		types.MaxBlockTxBytes,
+		"the max size of the block transaction",
+	)
+
+	fs.Int64Var(
+		&c.blockMaxDataBytes,
+		"block-max-data-bytes",
+		types.MaxBlockDataBytes,
+		"the max size of the block data",
+	)
+
+	fs.Int64Var(
+		&c.blockMaxGas,
+		"block-max-gas",
+		types.MaxBlockMaxGas,
+		"the max gas limit for the block",
+	)
+
+	fs.Int64Var(
+		&c.blockTimeIota,
+		"block-time-iota",
+		types.BlockTimeIotaMS,
+		"the block time iota (in ms)",
+	)
+}
+
+func execGenerate(cfg *generateCfg, io *commands.IO) error {
+	// Start with the default configuration
+	genesis := getDefaultGenesis()
+
+	// Set the genesis time
+	if cfg.genesisTime > 0 {
+		genesis.GenesisTime = time.Unix(cfg.genesisTime, 0)
+	}
+
+	// Set the chain ID
+	if cfg.chainID != "" {
+		genesis.ChainID = cfg.chainID
+	}
+
+	// Set the max tx bytes
+	if cfg.blockMaxTxBytes > 0 {
+		genesis.ConsensusParams.Block.MaxTxBytes = cfg.blockMaxTxBytes
+	}
+
+	// Set the max data bytes
+	if cfg.blockMaxDataBytes > 0 {
+		genesis.ConsensusParams.Block.MaxDataBytes = cfg.blockMaxDataBytes
+	}
+
+	// Set the max block gas
+	if cfg.blockMaxGas > 0 {
+		genesis.ConsensusParams.Block.MaxGas = cfg.blockMaxGas
+	}
+
+	// Set the block time IOTA
+	if cfg.blockTimeIota > 0 {
+		genesis.ConsensusParams.Block.TimeIotaMS = cfg.blockTimeIota
+	}
+
+	// Validate the genesis
+	if validateErr := genesis.ValidateAndComplete(); validateErr != nil {
+		return fmt.Errorf("unable to validate genesis, %w", validateErr)
+	}
+
+	// Save the genesis file to disk
+	if saveErr := genesis.SaveAs(cfg.outputPath); saveErr != nil {
+		return fmt.Errorf("unable to save genesis, %w", saveErr)
+	}
+
+	io.Printfln("Genesis successfully generated at %s", cfg.outputPath)
+
+	return nil
+}
+
+// getDefaultGenesis returns the default genesis config
+func getDefaultGenesis() *types.GenesisDoc {
+	return &types.GenesisDoc{
+		GenesisTime:     time.Now(),
+		ChainID:         defaultChainID,
+		ConsensusParams: types.DefaultConsensusParams(),
+	}
+}