Transaction signing and encoding (#95)

* WIP setting up evm tx command and updating emint keys output

* Fix linting issue

* Wip restructuring to allow for ethereum signing and encoding

* WIP setting up keybase and context to use Ethermint keys

* Fixed encoding and decoding of emint keys

* Adds command for generating explicit ethereum tx

* Fixed evm route for handling tx

* Fixed tx and msg encoding which allows transactions to be sent

* Added relevant documentation for changes and cleaned up code

* Added documentation and indicators why code was overriden

keys/add.go

@@ -90,7 +90,7 @@ func runAddCmd(cmd *cobra.Command, args []string) error {
 	interactive := viper.GetBool(flagInteractive)
 	showMnemonic := !viper.GetBool(flagNoBackup)
 
-	kb, err = clientkeys.NewKeyBaseFromHomeFlag()
+	kb, err = NewKeyBaseFromHomeFlag()
 	if err != nil {
 		return err
 	}

keys/show_test.go

@@ -7,7 +7,6 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"github.com/cosmos/cosmos-sdk/client/flags"
-	clientkeys "github.com/cosmos/cosmos-sdk/client/keys"
 	"github.com/cosmos/cosmos-sdk/tests"
 )
 
@@ -32,7 +31,7 @@ func TestRunShowCmd(t *testing.T) {
 
 	fakeKeyName1 := "runShowCmd_Key1"
 	fakeKeyName2 := "runShowCmd_Key2"
-	kb, err := clientkeys.NewKeyBaseFromHomeFlag()
+	kb, err := NewKeyBaseFromHomeFlag()
 	assert.NoError(t, err)
 	_, err = kb.CreateAccount(fakeKeyName1, tests.TestMnemonic, "", "", 0, 0)
 	assert.NoError(t, err)

keys/utils.go

@@ -2,28 +2,33 @@ package keys
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/spf13/viper"
 	"github.com/tendermint/tendermint/libs/cli"
 	"gopkg.in/yaml.v2"
 
-	"github.com/cosmos/cosmos-sdk/client/flags"
 	clientkeys "github.com/cosmos/cosmos-sdk/client/keys"
+
+	"github.com/cosmos/cosmos-sdk/client/flags"
 	cosmosKeys "github.com/cosmos/cosmos-sdk/crypto/keys"
+	emintKeys "github.com/cosmos/ethermint/crypto/keys"
 )
 
 // available output formats.
 const (
 	OutputFormatText = "text"
 	OutputFormatJSON = "json"
+
+	defaultKeyDBName = "emintkeys"
 )
 
-type bechKeyOutFn func(keyInfo cosmosKeys.Info) (cosmosKeys.KeyOutput, error)
+type bechKeyOutFn func(keyInfo cosmosKeys.Info) (emintKeys.KeyOutput, error)
 
 // GetKeyInfo returns key info for a given name. An error is returned if the
 // keybase cannot be retrieved or getting the info fails.
 func GetKeyInfo(name string) (cosmosKeys.Info, error) {
-	keybase, err := clientkeys.NewKeyBaseFromHomeFlag()
+	keybase, err := NewKeyBaseFromHomeFlag()
 	if err != nil {
 		return nil, err
 	}
@@ -31,6 +36,47 @@ func GetKeyInfo(name string) (cosmosKeys.Info, error) {
 	return keybase.Get(name)
 }
 
+// NewKeyBaseFromHomeFlag initializes a Keybase based on the configuration.
+func NewKeyBaseFromHomeFlag() (cosmosKeys.Keybase, error) {
+	rootDir := viper.GetString(flags.FlagHome)
+	return NewKeyBaseFromDir(rootDir)
+}
+
+// NewKeyBaseFromDir initializes a keybase at a particular dir.
+func NewKeyBaseFromDir(rootDir string) (cosmosKeys.Keybase, error) {
+	return getLazyKeyBaseFromDir(rootDir)
+}
+
+// NewInMemoryKeyBase returns a storage-less keybase.
+func NewInMemoryKeyBase() cosmosKeys.Keybase { return emintKeys.NewInMemory() }
+
+func getLazyKeyBaseFromDir(rootDir string) (cosmosKeys.Keybase, error) {
+	return emintKeys.New(defaultKeyDBName, filepath.Join(rootDir, defaultKeyDBName)), nil
+}
+
+// GetPassphrase returns a passphrase for a given name. It will first retrieve
+// the key info for that name if the type is local, it'll fetch input from
+// STDIN. Otherwise, an empty passphrase is returned. An error is returned if
+// the key info cannot be fetched or reading from STDIN fails.
+func GetPassphrase(name string) (string, error) {
+	var passphrase string
+
+	keyInfo, err := GetKeyInfo(name)
+	if err != nil {
+		return passphrase, err
+	}
+
+	// we only need a passphrase for locally stored keys
+	if keyInfo.GetType().String() == emintKeys.TypeLocal.String() {
+		passphrase, err = clientkeys.ReadPassphraseFromStdin(name)
+		if err != nil {
+			return passphrase, err
+		}
+	}
+
+	return passphrase, nil
+}
+
 func printKeyInfo(keyInfo cosmosKeys.Info, bechKeyOut bechKeyOutFn) {
 	ko, err := bechKeyOut(keyInfo)
 	if err != nil {
@@ -39,7 +85,7 @@ func printKeyInfo(keyInfo cosmosKeys.Info, bechKeyOut bechKeyOutFn) {
 
 	switch viper.Get(cli.OutputFlag) {
 	case OutputFormatText:
-		printTextInfos([]cosmosKeys.KeyOutput{ko})
+		printTextInfos([]emintKeys.KeyOutput{ko})
 
 	case OutputFormatJSON:
 		var out []byte
@@ -84,7 +130,7 @@ func printKeyInfo(keyInfo cosmosKeys.Info, bechKeyOut bechKeyOutFn) {
 // 	}
 // }
 
-func printTextInfos(kos []cosmosKeys.KeyOutput) {
+func printTextInfos(kos []emintKeys.KeyOutput) {
 	out, err := yaml.Marshal(&kos)
 	if err != nil {
 		panic(err)