fix: init with config chain-id (#9762)

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## Description

Closes: #9604, Ref: #9644

<!-- Add a description of the changes that this PR introduces and the files that
are the most critical to review. -->

The `init` command uses the `chain-id` from the client config if `--chain-id` is not provided.

---

### Author Checklist

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please add links to any relevant follow up issues.*

I have...

- [x] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [x] added `!` to the type prefix if API or client breaking change
- [x] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [x] provided a link to the relevant issue or specification
- [x] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules) -n/a
- [x] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [x] added a changelog entry to `CHANGELOG.md`
- [x] included comments for [documenting Go code](https://blog.golang.org/godoc) -n/a
- [x] updated the relevant documentation or specification -n/a
- [x] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

CHANGELOG.md

@@ -86,6 +86,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/distribution) [\#9599](https://github.com/cosmos/cosmos-sdk/pull/9599) Withdraw rewards event now includes a value attribute even if there are 0 rewards (due to situations like 100% commission).
 * (x/genutil) [\#9638](https://github.com/cosmos/cosmos-sdk/pull/9638) Added missing validator key save when recovering from mnemonic
 * (server) [#9704](https://github.com/cosmos/cosmos-sdk/pull/9704) Start GRPCWebServer in goroutine, avoid blocking other services from starting.
+* [\#9762](https://github.com/cosmos/cosmos-sdk/pull/9762) The init command uses the chain-id from the client config if --chain-id is not provided
 
 ### State Machine Breaking
 

x/genutil/client/cli/init.go

@@ -80,7 +80,11 @@ func InitCmd(mbm module.BasicManager, defaultNodeHome string) *cobra.Command {
 			config.SetRoot(clientCtx.HomeDir)
 
 			chainID, _ := cmd.Flags().GetString(flags.FlagChainID)
-			if chainID == "" {
+			switch {
+			case chainID != "":
+			case clientCtx.ChainID != "":
+				chainID = clientCtx.ChainID
+			default:
 				chainID = fmt.Sprintf("test-chain-%v", tmrand.Str(6))
 			}
 

x/genutil/client/cli/init_test.go

@@ -199,13 +199,60 @@ func TestStartStandAlone(t *testing.T) {
 func TestInitNodeValidatorFiles(t *testing.T) {
 	home := t.TempDir()
 	cfg, err := genutiltest.CreateDefaultTendermintConfig(home)
-	nodeID, valPubKey, err := genutil.InitializeNodeValidatorFiles(cfg)
+	require.NoError(t, err)
+
+	nodeID, valPubKey, err := genutil.InitializeNodeValidatorFiles(cfg)
+	require.NoError(t, err)
 
-	require.Nil(t, err)
 	require.NotEqual(t, "", nodeID)
 	require.NotEqual(t, 0, len(valPubKey.Bytes()))
 }
 
+func TestInitConfig(t *testing.T) {
+	home := t.TempDir()
+	logger := log.NewNopLogger()
+	cfg, err := genutiltest.CreateDefaultTendermintConfig(home)
+	require.NoError(t, err)
+
+	serverCtx := server.NewContext(viper.New(), cfg, logger)
+	interfaceRegistry := types.NewInterfaceRegistry()
+	marshaler := codec.NewProtoCodec(interfaceRegistry)
+	clientCtx := client.Context{}.
+		WithCodec(marshaler).
+		WithLegacyAmino(makeCodec()).
+		WithChainID("foo"). // add chain-id to clientCtx
+		WithHomeDir(home)
+
+	ctx := context.Background()
+	ctx = context.WithValue(ctx, client.ClientContextKey, &clientCtx)
+	ctx = context.WithValue(ctx, server.ServerContextKey, serverCtx)
+
+	cmd := genutilcli.InitCmd(testMbm, home)
+	cmd.SetArgs([]string{"testnode"})
+
+	require.NoError(t, cmd.ExecuteContext(ctx))
+
+	old := os.Stdout
+	r, w, _ := os.Pipe()
+	os.Stdout = w
+
+	cmd = server.ExportCmd(nil, home)
+	require.NoError(t, cmd.ExecuteContext(ctx))
+
+	outC := make(chan string)
+	go func() {
+		var buf bytes.Buffer
+		io.Copy(&buf, r)
+		outC <- buf.String()
+	}()
+
+	w.Close()
+	os.Stdout = old
+	out := <-outC
+
+	require.Contains(t, out, "\"chain_id\": \"foo\"")
+}
+
 // custom tx codec
 func makeCodec() *codec.LegacyAmino {
 	var cdc = codec.NewLegacyAmino()