[node.sh] added ExampleLoadKeys

cmd/harmony/blsloader/loader_test.go

@@ -2,10 +2,68 @@ package blsloader
 
 import (
 	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
 	"reflect"
 	"testing"
 )
 
+func ExampleLoadKeys() {
+	dir, err := prepareDataForExample()
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	config := Config{
+		BlsDir:        &dir,
+		PassSrcType:   PassSrcFile,  // not assign PassFile to dynamically use .pass path
+		AwsCfgSrcType: AwsCfgSrcNil, // disable loading file with kms
+	}
+
+	keys, err := LoadKeys(config)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	fmt.Printf("loaded %v keys\n", len(keys))
+	for i, key := range keys {
+		fmt.Printf("  key %v: %x\n", i, key.Pub.Bytes)
+	}
+	// Output:
+	//
+	// loaded 2 keys
+	//   key 0: 0e969f8b302cf7648bc39652ca7a279a8562b72933a3f7cddac2252583280c7c3495c9ae854f00f6dd19c32fc5a17500
+	//   key 1: 152beed46d7a0002ef0f960946008887eedd4775bdf2ed238809aa74e20d31fdca267443615cc6f4ede49d58911ee083
+}
+
+func prepareDataForExample() (string, error) {
+	unitTestDir := filepath.Join(baseTestDir, "ExampleLoadKeys")
+	os.Remove(unitTestDir)
+	os.MkdirAll(unitTestDir, 0700)
+
+	if err := writeKeyAndPass(unitTestDir, testKeys[0]); err != nil {
+		return "", err
+	}
+	if err := writeKeyAndPass(unitTestDir, testKeys[1]); err != nil {
+		return "", err
+	}
+	return unitTestDir, nil
+}
+
+func writeKeyAndPass(dir string, key testKey) error {
+	keyFile := filepath.Join(dir, key.publicKey+basicKeyExt)
+	if err := writeFile(keyFile, key.keyFileData); err != nil {
+		return fmt.Errorf("cannot write key file data: %v", err)
+	}
+	passFile := filepath.Join(dir, key.publicKey+passExt)
+	if err := writeFile(passFile, key.passphrase); err != nil {
+		return fmt.Errorf("cannot write pass file data: %v", err)
+	}
+	return nil
+}
+
 func TestGetKeyDecrypters(t *testing.T) {
 	tests := []struct {
 		config   Config