From b47978874a799f8e0597b4a85b96a1ad97b22009 Mon Sep 17 00:00:00 2001
From: Cedric Meury <cedric@meury.com>
Date: Tue, 26 Jun 2018 14:04:23 +0200
Subject: [PATCH] return non-zero exitcode when encountering any change on
 upgrade

---
 README.md      |  1 +
 cmd/upgrade.go | 29 ++++++++++++++++++-----------
 diff/diff.go   | 32 ++++++++++++++++++++++++++------
 main.go        |  2 ++
 4 files changed, 47 insertions(+), 17 deletions(-)

diff --git a/README.md b/README.md
index 1e35cad3..5b5fe747 100644
--- a/README.md
+++ b/README.md
@@ -76,6 +76,7 @@ Examples:
 
 Flags:
   -h, --help                   help for upgrade
+      --detailed-exitcode      return a non-zero exit code when there are changes
       --reset-values           reset the values to the ones built into the chart and merge in any new values
       --reuse-values           reuse the last release's values and merge in any new values
       --set stringArray        set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
diff --git a/cmd/upgrade.go b/cmd/upgrade.go
index 4577be84..858ca1e6 100644
--- a/cmd/upgrade.go
+++ b/cmd/upgrade.go
@@ -9,19 +9,21 @@ import (
 	"github.com/databus23/helm-diff/manifest"
 	"github.com/spf13/cobra"
 	"k8s.io/helm/pkg/helm"
+	"errors"
 )
 
 type diffCmd struct {
-	release         string
-	chart           string
-	chartVersion    string
-	client          helm.Interface
-	valueFiles      valueFiles
-	values          []string
-	reuseValues     bool
-	resetValues     bool
-	allowUnreleased bool
-	suppressedKinds []string
+	release         	string
+	chart           	string
+	chartVersion    	string
+	client          	helm.Interface
+	valueFiles      	valueFiles
+	values          	[]string
+	reuseValues     	bool
+	resetValues     	bool
+	allowUnreleased 	bool
+	detailedExitCode 	bool
+	suppressedKinds 	[]string
 }
 
 const globalUsage = `Show a diff explaining what a helm upgrade would change.
@@ -67,6 +69,7 @@ func newChartCommand() *cobra.Command {
 	f.BoolVar(&diff.resetValues, "reset-values", false, "reset the values to the ones built into the chart and merge in any new values")
 	f.BoolVar(&diff.allowUnreleased, "allow-unreleased", false, "enables diffing of releases that are not yet deployed via Helm")
 	f.StringArrayVar(&diff.suppressedKinds, "suppress", []string{}, "allows suppression of the values listed in the diff output")
+	f.BoolVar(&diff.detailedExitCode, "detailed-exitcode", false, "return a non-zero exit code when there are changes")
 
 	return cmd
 
@@ -137,7 +140,11 @@ func (d *diffCmd) run() error {
 		newSpecs = manifest.Parse(upgradeResponse.Release.Manifest)
 	}
 
-	diff.DiffManifests(currentSpecs, newSpecs, d.suppressedKinds, os.Stdout)
+	seenAnyChanges := diff.DiffManifests(currentSpecs, newSpecs, d.suppressedKinds, os.Stdout)
+
+	if d.detailedExitCode && seenAnyChanges {
+		return errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)")
+	}
 
 	return nil
 }
diff --git a/diff/diff.go b/diff/diff.go
index 2872a446..a92a99b0 100644
--- a/diff/diff.go
+++ b/diff/diff.go
@@ -11,18 +11,29 @@ import (
 	"github.com/databus23/helm-diff/manifest"
 )
 
-func DiffManifests(oldIndex, newIndex map[string]*manifest.MappingResult, suppressedKinds []string, to io.Writer) {
+
+func DiffManifests(oldIndex, newIndex map[string]*manifest.MappingResult, suppressedKinds []string, to io.Writer) bool {
+	seenAnyChanges := false
+	emptyMapping := &manifest.MappingResult{}
 	for key, oldContent := range oldIndex {
 		if newContent, ok := newIndex[key]; ok {
 			if oldContent.Content != newContent.Content {
 				// modified
 				fmt.Fprintf(to, ansi.Color("%s has changed:", "yellow")+"\n", key)
-				printDiff(suppressedKinds, oldContent.Kind, oldContent.Content, newContent.Content, to)
+				diffs := generateDiff(oldContent, newContent)
+				if len(diffs) > 0 {
+					seenAnyChanges = true
+				}
+				printDiff(suppressedKinds, oldContent.Kind, diffs, to)
 			}
 		} else {
 			// removed
 			fmt.Fprintf(to, ansi.Color("%s has been removed:", "yellow")+"\n", key)
-			printDiff(suppressedKinds, oldContent.Kind, oldContent.Content, "", to)
+			diffs := generateDiff(oldContent, emptyMapping)
+			if len(diffs) > 0 {
+				seenAnyChanges = true
+			}
+			printDiff(suppressedKinds, oldContent.Kind, diffs, to)
 		}
 	}
 
@@ -30,13 +41,22 @@ func DiffManifests(oldIndex, newIndex map[string]*manifest.MappingResult, suppre
 		if _, ok := oldIndex[key]; !ok {
 			// added
 			fmt.Fprintf(to, ansi.Color("%s has been added:", "yellow")+"\n", key)
-			printDiff(suppressedKinds, newContent.Kind, "", newContent.Content, to)
+			diffs := generateDiff(emptyMapping, newContent)
+			if len(diffs) > 0 {
+				seenAnyChanges = true
+			}
+			printDiff(suppressedKinds, newContent.Kind, diffs, to)
 		}
 	}
+	return seenAnyChanges
+}
+
+func generateDiff(oldContent *manifest.MappingResult, newContent *manifest.MappingResult) []difflib.DiffRecord {
+	const sep = "\n"
+	return difflib.Diff(strings.Split(oldContent.Content, sep), strings.Split(newContent.Content, sep))
 }
 
-func printDiff(suppressedKinds []string, kind, before, after string, to io.Writer) {
-	diffs := difflib.Diff(strings.Split(before, "\n"), strings.Split(after, "\n"))
+func printDiff(suppressedKinds []string, kind string, diffs []difflib.DiffRecord, to io.Writer) {
 
 	for _, ckind := range suppressedKinds {
 		if ckind == kind {
diff --git a/main.go b/main.go
index 42e4da20..1f56f4cc 100644
--- a/main.go
+++ b/main.go
@@ -2,12 +2,14 @@ package main
 
 import (
 	"os"
+	"fmt"
 
 	"github.com/databus23/helm-diff/cmd"
 )
 
 func main() {
 	if err := cmd.New().Execute(); err != nil {
+		fmt.Println(err)
 		os.Exit(1)
 	}
 }