From b210eb7dcdcb1b5c79d22ee07298b8ffb647c337 Mon Sep 17 00:00:00 2001
From: Nobi <nobi@nobidev.com>
Date: Sat, 26 Mar 2022 03:20:24 +0000
Subject: [PATCH 1/2] Allow marshal to bytes buffer

---
 viper.go      | 9 +++++++++
 viper_test.go | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/viper.go b/viper.go
index 0158a7f..571ea52 100644
--- a/viper.go
+++ b/viper.go
@@ -1704,6 +1704,15 @@ func (v *Viper) SafeWriteConfigAs(filename string) error {
 	return v.writeConfig(filename, false)
 }
 
+// Marshal will return a Buffer containing the content that should have been written to the file
+func (v *Viper) Marshal() (*bytes.Buffer, error) {
+	data, err := v.encoderRegistry.Encode(v.getConfigType(), v.AllSettings())
+	if err != nil {
+		return nil, err
+	}
+	return bytes.NewBuffer(data), nil
+}
+
 func (v *Viper) writeConfig(filename string, force bool) error {
 	v.logger.Info("attempting to write configuration to file")
 
diff --git a/viper_test.go b/viper_test.go
index e0bfc57..ffcd5fe 100644
--- a/viper_test.go
+++ b/viper_test.go
@@ -1979,6 +1979,15 @@ func TestSafeWriteConfigAsWithExistingFile(t *testing.T) {
 	assert.True(t, ok, "Expected ConfigFileAlreadyExistsError")
 }
 
+func TestMarshal(t *testing.T) {
+	v := New()
+	v.SetConfigType("yaml")
+	require.NoError(t, v.ReadConfig(bytes.NewBuffer(yamlExample)))
+	c, err := v.Marshal()
+	require.NoError(t, err)
+	assert.Equal(t, c.Bytes(), yamlWriteExpected)
+}
+
 func TestWriteHiddenFile(t *testing.T) {
 	v := New()
 	fs := afero.NewMemMapFs()

From e648540a6ac25a5a17bafba9e65c9096b6f6b34b Mon Sep 17 00:00:00 2001
From: Nobi <nobi@nobidev.com>
Date: Tue, 25 Jul 2023 22:43:18 +0700
Subject: [PATCH 2/2] Add new method `Encode` to Viper that allows loading
 rawVal into config and merging it with the current config map

---
 viper.go           | 10 ++++++++++
 viper_test.go      | 26 ++++++++++++++++++++++++++
 viper_yaml_test.go |  4 ++++
 3 files changed, 40 insertions(+)

diff --git a/viper.go b/viper.go
index 571ea52..3e8f819 100644
--- a/viper.go
+++ b/viper.go
@@ -1704,6 +1704,16 @@ func (v *Viper) SafeWriteConfigAs(filename string) error {
 	return v.writeConfig(filename, false)
 }
 
+// Encode will load the rawVal into config, then you can write to file
+func (v *Viper) Encode(rawVal interface{}, opts ...DecoderConfigOption) error {
+	var cfg map[string]interface{}
+	err := decode(rawVal, defaultDecoderConfig(&cfg, opts...))
+	if err != nil {
+		return err
+	}
+	return v.MergeConfigMap(cfg)
+}
+
 // Marshal will return a Buffer containing the content that should have been written to the file
 func (v *Viper) Marshal() (*bytes.Buffer, error) {
 	data, err := v.encoderRegistry.Encode(v.getConfigType(), v.AllSettings())
diff --git a/viper_test.go b/viper_test.go
index ffcd5fe..d2a03b6 100644
--- a/viper_test.go
+++ b/viper_test.go
@@ -1979,6 +1979,18 @@ func TestSafeWriteConfigAsWithExistingFile(t *testing.T) {
 	assert.True(t, ok, "Expected ConfigFileAlreadyExistsError")
 }
 
+func TestEncode(t *testing.T) {
+	type config struct {
+		Age   int
+		Beard bool
+	}
+	C := &config{35, true}
+	v := New()
+	require.NoError(t, v.Encode(C))
+	expected := map[string]interface{}{"age": 35, "beard": true}
+	assert.Equal(t, v.config, expected)
+}
+
 func TestMarshal(t *testing.T) {
 	v := New()
 	v.SetConfigType("yaml")
@@ -1988,6 +2000,20 @@ func TestMarshal(t *testing.T) {
 	assert.Equal(t, c.Bytes(), yamlWriteExpected)
 }
 
+func TestEncodeAndMarshal(t *testing.T) {
+	type config struct {
+		Age   int
+		Beard bool
+	}
+	C := &config{35, true}
+	v := New()
+	require.NoError(t, v.Encode(C))
+	v.SetConfigType("yaml")
+	c, err := v.Marshal()
+	require.NoError(t, err)
+	assert.Equal(t, c.Bytes(), yamlEncodeWriteExpected)
+}
+
 func TestWriteHiddenFile(t *testing.T) {
 	v := New()
 	fs := afero.NewMemMapFs()
diff --git a/viper_yaml_test.go b/viper_yaml_test.go
index 264446b..ec1ce1c 100644
--- a/viper_yaml_test.go
+++ b/viper_yaml_test.go
@@ -51,3 +51,7 @@ emails:
         created: 01/02/03
         active: true
 `)
+
+var yamlEncodeWriteExpected = []byte(`age: 35
+beard: true
+`)