From 0a0a6e10180ac245f95b7595b0bb82e82acf78be Mon Sep 17 00:00:00 2001
From: Petr Michalec <epcim@apealive.net>
Date: Tue, 15 Dec 2020 08:38:37 +0100
Subject: [PATCH] helm values on inflator config - plugin

Signed-off-by: Petr Michalec <epcim@apealive.net>
---
 .../HelmChartInflationGenerator.go            | 72 +++++++++++++++++++
 .../helmchartinflationgenerator/go.mod        |  1 +
 .../helmchartinflationgenerator/go.sum        |  1 +
 3 files changed, 74 insertions(+)

diff --git a/plugin/builtin/helmchartinflationgenerator/HelmChartInflationGenerator.go b/plugin/builtin/helmchartinflationgenerator/HelmChartInflationGenerator.go
index 004bc23b8..d297f0cf4 100644
--- a/plugin/builtin/helmchartinflationgenerator/HelmChartInflationGenerator.go
+++ b/plugin/builtin/helmchartinflationgenerator/HelmChartInflationGenerator.go
@@ -13,12 +13,15 @@ package main
 import (
 	"bytes"
 	"fmt"
+	"io"
+	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
 	"regexp"
 	"strings"
 
+	"github.com/imdario/mergo"
 	"github.com/pkg/errors"
 	"sigs.k8s.io/kustomize/api/filesys"
 	"sigs.k8s.io/kustomize/api/resmap"
@@ -70,6 +73,9 @@ func (p *HelmChartInflationGeneratorPlugin) Config(h *resmap.PluginHelpers, conf
 	if p.Values == "" {
 		p.Values = path.Join(p.ChartHome, p.ChartName, "values.yaml")
 	}
+	if p.ValuesMerge == "" {
+		p.ValuesMerge = "override"
+	}
 	// runHelmCommand will run `helm` command with args provided. Return stdout
 	// and error if there is any.
 	p.runHelmCommand = func(args []string) ([]byte, error) {
@@ -96,6 +102,63 @@ func (p *HelmChartInflationGeneratorPlugin) Config(h *resmap.PluginHelpers, conf
 	return nil
 }
 
+// EncodeValues for writing
+func (p *HelmChartInflationGeneratorPlugin) EncodeValues(w io.Writer) error {
+	d, err := yaml.Marshal(p.ValuesLocal)
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(d)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// useValuesLocal process (merge) inflator config provided values with chart default values.yaml
+func (p *HelmChartInflationGeneratorPlugin) useValuesLocal() error {
+	fn := path.Join(p.ChartHome, p.ChartName, "kustomize-values.yaml")
+	vf, err := os.Create(fn)
+	defer vf.Close()
+	if err != nil {
+		return err
+	}
+	// override, merge, none
+	if p.ValuesMerge == "none" || p.ValuesMerge == "no" || p.ValuesMerge == "false" {
+		p.Values = fn
+	} else {
+		pValues, err := ioutil.ReadFile(p.Values)
+		if err != nil {
+			return err
+		}
+		chValues := make(map[string]interface{})
+		err = yaml.Unmarshal(pValues, &chValues)
+		if err != nil {
+			return err
+		}
+		if p.ValuesMerge == "override" {
+			err = mergo.Merge(&chValues, p.ValuesLocal, mergo.WithOverride)
+			if err != nil {
+				return err
+			}
+		}
+		if p.ValuesMerge == "merge" {
+			err = mergo.Merge(&chValues, p.ValuesLocal)
+			if err != nil {
+				return err
+			}
+		}
+		p.ValuesLocal = chValues
+		p.Values = fn
+	}
+	err = p.EncodeValues(vf)
+	if err != nil {
+		return err
+	}
+	vf.Sync()
+	return nil
+}
+
 // Generate implements generator
 func (p *HelmChartInflationGeneratorPlugin) Generate() (resmap.ResMap, error) {
 	// cleanup
@@ -112,6 +175,15 @@ func (p *HelmChartInflationGeneratorPlugin) Generate() (resmap.ResMap, error) {
 			return nil, err
 		}
 	}
+
+	// inflator config valuesLocal
+	if len(p.ValuesLocal) > 0 {
+		err := p.useValuesLocal()
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	// render the charts
 	stdout, err := p.runHelmCommand(p.getTemplateCommandArgs())
 	if err != nil {
diff --git a/plugin/builtin/helmchartinflationgenerator/go.mod b/plugin/builtin/helmchartinflationgenerator/go.mod
index 204fed0a2..91b38edc3 100644
--- a/plugin/builtin/helmchartinflationgenerator/go.mod
+++ b/plugin/builtin/helmchartinflationgenerator/go.mod
@@ -3,6 +3,7 @@ module sigs.k8s.io/kustomize/plugin/builtin/helmchartinflationgenerator
 go 1.15
 
 require (
+	github.com/imdario/mergo v0.3.5
 	github.com/pkg/errors v0.8.1
 	sigs.k8s.io/kustomize/api v0.7.0
 	sigs.k8s.io/yaml v1.2.0
diff --git a/plugin/builtin/helmchartinflationgenerator/go.sum b/plugin/builtin/helmchartinflationgenerator/go.sum
index f6b4afa27..5f6f8b97b 100644
--- a/plugin/builtin/helmchartinflationgenerator/go.sum
+++ b/plugin/builtin/helmchartinflationgenerator/go.sum
@@ -216,6 +216,7 @@ github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
+github.com/imdario/mergo v0.3.5 h1:JboBksRwiiAJWvIYJVo46AfV+IAIKZpfrSzVKj42R4Q=
 github.com/imdario/mergo v0.3.5/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=