From 711ed74e091f2ada6e2aa84e5e62b9696b589d8a Mon Sep 17 00:00:00 2001
From: meowsbits <45600330+meowsbits@users.noreply.github.com>
Date: Tue, 4 Feb 2020 04:49:13 -0600
Subject: [PATCH] cmd/geth: add 'dumpgenesis' command (#20191)

Adds the 'geth dumpgenesis' command, which writes the configured
genesis in JSON format to stdout. This provides a way to generate the
data (structure and content) that can then be used with the 'geth init'
command.
---
 cmd/geth/chaincmd.go | 23 +++++++++++++++++++++++
 cmd/geth/main.go     |  1 +
 2 files changed, 24 insertions(+)

diff --git a/cmd/geth/chaincmd.go b/cmd/geth/chaincmd.go
index 49e6a0594..5b176b6da 100644
--- a/cmd/geth/chaincmd.go
+++ b/cmd/geth/chaincmd.go
@@ -56,6 +56,18 @@ This is a destructive action and changes the network in which you will be
 participating.
 
 It expects the genesis file as argument.`,
+	}
+	dumpGenesisCommand = cli.Command{
+		Action:    utils.MigrateFlags(dumpGenesis),
+		Name:      "dumpgenesis",
+		Usage:     "Dumps genesis block JSON configuration to stdout",
+		ArgsUsage: "",
+		Flags: []cli.Flag{
+			utils.DataDirFlag,
+		},
+		Category: "BLOCKCHAIN COMMANDS",
+		Description: `
+The dumpgenesis command dumps the genesis block configuration in JSON format to stdout.`,
 	}
 	importCommand = cli.Command{
 		Action:    utils.MigrateFlags(importChain),
@@ -227,6 +239,17 @@ func initGenesis(ctx *cli.Context) error {
 	return nil
 }
 
+func dumpGenesis(ctx *cli.Context) error {
+	genesis := utils.MakeGenesis(ctx)
+	if genesis == nil {
+		genesis = core.DefaultGenesisBlock()
+	}
+	if err := json.NewEncoder(os.Stdout).Encode(genesis); err != nil {
+		utils.Fatalf("could not encode genesis")
+	}
+	return nil
+}
+
 func importChain(ctx *cli.Context) error {
 	if len(ctx.Args()) < 1 {
 		utils.Fatalf("This command requires an argument.")
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 8db19077a..0369e527b 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -205,6 +205,7 @@ func init() {
 		copydbCommand,
 		removedbCommand,
 		dumpCommand,
+		dumpGenesisCommand,
 		inspectCommand,
 		// See accountcmd.go:
 		accountCommand,