Reorganize cobra cmd to enable better reuse

cmd/common.go

@@ -0,0 +1,119 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	data "github.com/tendermint/go-data"
+	"github.com/tendermint/go-data/base58"
+)
+
+/*******
+
+TODO
+
+This file should move into go-common or the like as a basis for all cli tools.
+It is here for experimentation of re-use between go-keys and light-client.
+
+*********/
+
+const (
+	RootFlag   = "root"
+	OutputFlag = "output"
+)
+
+func PrepareMainCmd(cmd *cobra.Command, envPrefix, defautRoot string) func() {
+	cobra.OnInitialize(func() { initEnv(envPrefix) })
+	cmd.PersistentFlags().StringP(RootFlag, "r", defautRoot, "root directory for config and data")
+	cmd.PersistentFlags().StringP("encoding", "e", "hex", "Binary encoding (hex|b64|btc)")
+	cmd.PersistentFlags().StringP(OutputFlag, "o", "text", "Output format (text|json)")
+	cmd.PersistentPreRunE = multiE(bindFlags, setEncoding, validateOutput, cmd.PersistentPreRunE)
+	return func() { execute(cmd) }
+}
+
+// initEnv sets to use ENV variables if set.
+func initEnv(prefix string) {
+	// env variables with TM prefix (eg. TM_ROOT)
+	viper.SetEnvPrefix(prefix)
+	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+	viper.AutomaticEnv()
+}
+
+// execute adds all child commands to the root command sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func execute(cmd *cobra.Command) {
+	if err := cmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(-1)
+	}
+}
+
+type wrapE func(cmd *cobra.Command, args []string) error
+
+func multiE(fs ...wrapE) wrapE {
+	return func(cmd *cobra.Command, args []string) error {
+		for _, f := range fs {
+			if f != nil {
+				if err := f(cmd, args); err != nil {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+}
+
+func bindFlags(cmd *cobra.Command, args []string) error {
+	// cmd.Flags() includes flags from this command and all persistent flags from the parent
+	if err := viper.BindPFlags(cmd.Flags()); err != nil {
+		return err
+	}
+
+	// rootDir is command line flag, env variable, or default $HOME/.tlc
+	rootDir := viper.GetString("root")
+	viper.SetConfigName("config") // name of config file (without extension)
+	viper.AddConfigPath(rootDir)  // search root directory
+
+	// If a config file is found, read it in.
+	if err := viper.ReadInConfig(); err == nil {
+		// stderr, so if we redirect output to json file, this doesn't appear
+		// fmt.Fprintln(os.Stderr, "Using config file:", viper.ConfigFileUsed())
+	} else if _, ok := err.(viper.ConfigFileNotFoundError); !ok {
+		// we ignore not found error, only parse error
+		// stderr, so if we redirect output to json file, this doesn't appear
+		fmt.Fprintf(os.Stderr, "%#v", err)
+	}
+	return nil
+}
+
+// setEncoding reads the encoding flag
+func setEncoding(cmd *cobra.Command, args []string) error {
+	// validate and set encoding
+	enc := viper.GetString("encoding")
+	switch enc {
+	case "hex":
+		data.Encoder = data.HexEncoder
+	case "b64":
+		data.Encoder = data.B64Encoder
+	case "btc":
+		data.Encoder = base58.BTCEncoder
+	default:
+		return errors.Errorf("Unsupported encoding: %s", enc)
+	}
+	return nil
+}
+
+func validateOutput(cmd *cobra.Command, args []string) error {
+	// validate output format
+	output := viper.GetString(OutputFlag)
+	switch output {
+	case "text", "json":
+	default:
+		return errors.Errorf("Unsupported output format: %s", output)
+	}
+	return nil
+}

cmd/get.go

@@ -32,7 +32,7 @@ var getCmd = &cobra.Command{
 		}
 		name := args[0]
 
-		info, err := manager.Get(name)
+		info, err := Manager.Get(name)
 		if err != nil {
 			fmt.Println(err.Error())
 			return

cmd/keys/main.go

@@ -14,8 +14,15 @@
 
 package main
 
-import "github.com/tendermint/go-keys/cmd"
+import (
+	"os"
+
+	"github.com/tendermint/go-keys/cmd"
+)
 
 func main() {
-	cmd.Execute()
+	cmd.RootCmd.PersistentPreRunE = cmd.SetupKeys
+	cmd.PrepareMainCmd(cmd.RootCmd, "TM", os.ExpandEnv("$HOME/.tlc"))
+	cmd.RootCmd.Execute()
+	// exec()
 }

cmd/list.go

@@ -27,7 +27,7 @@ var listCmd = &cobra.Command{
 	Long: `Return a list of all public keys stored by this key manager
 along with their associated name and address.`,
 	Run: func(cmd *cobra.Command, args []string) {
-		infos, err := manager.List()
+		infos, err := Manager.List()
 		if err != nil {
 			fmt.Println(err.Error())
 			return

cmd/new.go

@@ -50,7 +50,7 @@ func newPassword(cmd *cobra.Command, args []string) {
 		return
 	}
 
-	info, err := manager.Create(name, pass, algo)
+	info, err := Manager.Create(name, pass, algo)
 	if err != nil {
 		fmt.Println(err.Error())
 		return

cmd/root.go

@@ -15,26 +15,19 @@
 package cmd
 
 import (
-	"fmt"
-	"os"
 	"path/filepath"
-	"strings"
 
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
-	data "github.com/tendermint/go-data"
-	"github.com/tendermint/go-data/base58"
 	keys "github.com/tendermint/go-keys"
 	"github.com/tendermint/go-keys/cryptostore"
 	"github.com/tendermint/go-keys/storage/filestorage"
 )
 
+const KeySubdir = "keys"
+
 var (
-	rootDir string
-	output  string
-	keyDir  string
-	manager keys.Manager
+	Manager keys.Manager
 )
 
 // RootCmd represents the base command when called without any subcommands
@@ -46,87 +39,19 @@ var RootCmd = &cobra.Command{
 These keys may be in any format supported by go-crypto and can be
 used by light-clients, full nodes, or any other application that
 needs to sign with a private key.`,
-	PersistentPreRunE: bindFlags,
-}
-
-// Execute adds all child commands to the root command sets flags appropriately.
-// This is called by main.main(). It only needs to happen once to the rootCmd.
-func Execute() {
-	if err := RootCmd.Execute(); err != nil {
-		fmt.Println(err)
-		os.Exit(-1)
-	}
-}
-
-func init() {
-	cobra.OnInitialize(initEnv)
-	RootCmd.PersistentFlags().StringP("root", "r", os.ExpandEnv("$HOME/.tlc"), "root directory for config and data")
-	RootCmd.PersistentFlags().String("keydir", "keys", "Directory to store private keys (subdir of root)")
-	RootCmd.PersistentFlags().StringP("output", "o", "text", "Output format (text|json)")
-	RootCmd.PersistentFlags().StringP("encoding", "e", "hex", "Binary encoding (hex|b64|btc)")
-}
-
-// initEnv sets to use ENV variables if set.
-func initEnv() {
-	// env variables with TM prefix (eg. TM_ROOT)
-	viper.SetEnvPrefix("TM")
-	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
-	viper.AutomaticEnv()
 }
 
-func bindFlags(cmd *cobra.Command, args []string) error {
-	// cmd.Flags() includes flags from this command and all persistent flags from the parent
-	if err := viper.BindPFlags(cmd.Flags()); err != nil {
-		return err
-	}
-
-	// rootDir is command line flag, env variable, or default $HOME/.tlc
-	rootDir = viper.GetString("root")
-	viper.SetConfigName("keys")  // name of config file (without extension)
-	viper.AddConfigPath(rootDir) // search root directory
-
-	// If a config file is found, read it in.
-	if err := viper.ReadInConfig(); err == nil {
-		// stderr, so if we redirect output to json file, this doesn't appear
-		fmt.Fprintln(os.Stderr, "Using config file:", viper.ConfigFileUsed())
-	}
-
-	return validateFlags(cmd)
-}
-
-// validateFlags asserts all RootCmd flags are valid
-func validateFlags(cmd *cobra.Command) error {
-	// validate output format
-	output = viper.GetString("output")
-	switch output {
-	case "text", "json":
-	default:
-		return errors.Errorf("Unsupported output format: %s", output)
-	}
-
-	// validate and set encoding
-	enc := viper.GetString("encoding")
-	switch enc {
-	case "hex":
-		data.Encoder = data.HexEncoder
-	case "b64":
-		data.Encoder = data.B64Encoder
-	case "btc":
-		data.Encoder = base58.BTCEncoder
-	default:
-		return errors.Errorf("Unsupported encoding: %s", enc)
-	}
-
+// SetupKeys must be registered in main() on the top level command
+// here this is RootCmd, but if we embed keys in eg. light-client,
+// that must be responsible for the update
+func SetupKeys(cmd *cobra.Command, args []string) error {
 	// store the keys directory
-	keyDir = viper.GetString("keydir")
-	if !filepath.IsAbs(keyDir) {
-		keyDir = filepath.Join(rootDir, keyDir)
-	}
+	rootDir := viper.GetString("root")
+	keyDir := filepath.Join(rootDir, KeySubdir)
 	// and construct the key manager
-	manager = cryptostore.New(
+	Manager = cryptostore.New(
 		cryptostore.SecretBox,
 		filestorage.New(keyDir),
 	)
-
 	return nil
 }

cmd/serve.go

@@ -64,7 +64,7 @@ func serveHTTP(cmd *cobra.Command, args []string) error {
 	}
 
 	router := mux.NewRouter()
-	ks := server.New(manager, viper.GetString("type"))
+	ks := server.New(Manager, viper.GetString("type"))
 	ks.Register(router)
 
 	// only set cors for tcp listener

cmd/update.go

@@ -50,7 +50,7 @@ func updatePassword(cmd *cobra.Command, args []string) {
 		return
 	}
 
-	err = manager.Update(name, oldpass, newpass)
+	err = Manager.Update(name, oldpass, newpass)
 	if err != nil {
 		fmt.Println(err.Error())
 	} else {

cmd/utils.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/bgentry/speakeasy"
 	"github.com/pkg/errors"
+	"github.com/spf13/viper"
 	data "github.com/tendermint/go-data"
 	keys "github.com/tendermint/go-keys"
 )
@@ -39,7 +40,7 @@ func getCheckPassword(prompt, prompt2 string) (string, error) {
 }
 
 func printInfo(info keys.Info) {
-	switch output {
+	switch viper.Get(OutputFlag) {
 	case "text":
 		addr, err := data.ToText(info.Address)
 		if err != nil {
@@ -60,7 +61,7 @@ func printInfo(info keys.Info) {
 }
 
 func printInfos(infos keys.Infos) {
-	switch output {
+	switch viper.Get(OutputFlag) {
 	case "text":
 		fmt.Println("All keys:")
 		for _, i := range infos {