support dockerhub credentials when pulling with kaniko-ecr (#27)

pkg/docker/config.go

@@ -0,0 +1,34 @@
+package docker
+
+import (
+	"encoding/base64"
+	"fmt"
+)
+
+type (
+	Auth struct {
+		Auth string `json:"auth"`
+	}
+
+	Config struct {
+		Auths       map[string]Auth   `json:"auths"`
+		CredHelpers map[string]string `json:"credHelpers"`
+	}
+)
+
+func NewConfig() *Config {
+	return &Config{
+		Auths:       map[string]Auth{},
+		CredHelpers: map[string]string{},
+	}
+}
+
+func (c *Config) SetAuth(registry, username, password string) {
+	authBytes := []byte(fmt.Sprintf("%s:%s", username, password))
+	encodedString := base64.StdEncoding.EncodeToString(authBytes)
+	c.Auths[registry] = Auth{Auth: encodedString}
+}
+
+func (c *Config) SetCredHelper(registry, helper string) {
+	c.CredHelpers[registry] = helper
+}