feat: Dedicated exit code (2) on there's diff (#78)

This feature is enabled only when the `--detailed-exitcode` flag (#65) is provided.
Supports `upgrade`, `revision` and `rollback` sub-commands.

Resolves #54, but only after helm/helm#4367 is released with helm v2.11.0, probably.

Author: mumoshu

Makefile

@@ -9,6 +9,11 @@ LDFLAGS := -X $(PKG)/cmd.Version=$(VERSION)
 LDFLAGS += -X $(PKG)/vendor/k8s.io/helm/pkg/version.BuildMetadata=
 LDFLAGS += -X $(PKG)/vendor/k8s.io/helm/pkg/version.Version=$(shell grep -A1 "package: k8s.io/helm" glide.yaml | sed -n -e 's/[ ]*version:.*\(v[.0-9]*\).*/\1/p')
 
+.PHONY: format
+format:
+	test -z "$$(find . -path ./vendor -prune -type f -o -name '*.go' -exec gofmt -d {} + | tee /dev/stderr)" || \
+	test -z "$$(find . -path ./vendor -prune -type f -o -name '*.go' -exec gofmt -w {} + | tee /dev/stderr)"
+
 .PHONY: install
 install: build
 	mkdir -p $(HELM_HOME)/plugins/helm-diff/bin

cmd/error.go

@@ -0,0 +1,6 @@
+package cmd
+
+type Error struct {
+	error
+	Code int
+}

cmd/revision.go

@@ -13,11 +13,12 @@ import (
 )
 
 type revision struct {
-	release         string
-	client          helm.Interface
-	suppressedKinds []string
-	revisions       []string
-	outputContext   int
+	release          string
+	client           helm.Interface
+	detailedExitCode bool
+	suppressedKinds  []string
+	revisions        []string
+	outputContext    int
 }
 
 const revisionCmdLongUsage = `
@@ -121,13 +122,20 @@ func (d *revision) differentiate() error {
 			return prettyError(err)
 		}
 
-		diff.DiffManifests(
+		seenAnyChanges := diff.DiffManifests(
 			manifest.ParseRelease(revisionResponse1.Release),
 			manifest.ParseRelease(revisionResponse2.Release),
 			d.suppressedKinds,
 			d.outputContext,
 			os.Stdout)
 
+		if d.detailedExitCode && seenAnyChanges {
+			return Error{
+				error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+				Code:  2,
+			}
+		}
+
 	default:
 		return errors.New("Invalid Arguments")
 	}

cmd/rollback.go

@@ -5,18 +5,20 @@ import (
 	"os"
 	"strconv"
 
+	"errors"
 	"github.com/databus23/helm-diff/diff"
 	"github.com/databus23/helm-diff/manifest"
 	"github.com/spf13/cobra"
 	"k8s.io/helm/pkg/helm"
 )
 
 type rollback struct {
-	release         string
-	client          helm.Interface
-	suppressedKinds []string
-	revisions       []string
-	outputContext   int
+	release          string
+	client           helm.Interface
+	detailedExitCode bool
+	suppressedKinds  []string
+	revisions        []string
+	outputContext    int
 }
 
 const rollbackCmdLongUsage = `
@@ -88,12 +90,19 @@ func (d *rollback) backcast() error {
 	}
 
 	// create a diff between the current manifest and the version of the manifest that a user is intended to rollback
-	diff.DiffManifests(
+	seenAnyChanges := diff.DiffManifests(
 		manifest.ParseRelease(releaseResponse.Release),
 		manifest.ParseRelease(revisionResponse.Release),
 		d.suppressedKinds,
 		d.outputContext,
 		os.Stdout)
 
+	if d.detailedExitCode && seenAnyChanges {
+		return Error{
+			error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+			Code:  2,
+		}
+	}
+
 	return nil
 }

cmd/upgrade.go

@@ -5,26 +5,26 @@ import (
 	"os"
 	"strings"
 
+	"errors"
 	"github.com/databus23/helm-diff/diff"
 	"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
-	detailedExitCode 	bool
-	valueFiles        valueFiles
-	values            []string
-	reuseValues       bool
-	resetValues       bool
-	allowUnreleased   bool
-	suppressedKinds   []string
-	outputContext     int
+	release          string
+	chart            string
+	chartVersion     string
+	client           helm.Interface
+	detailedExitCode bool
+	valueFiles       valueFiles
+	values           []string
+	reuseValues      bool
+	resetValues      bool
+	allowUnreleased  bool
+	suppressedKinds  []string
+	outputContext    int
 }
 
 const globalUsage = `Show a diff explaining what a helm upgrade would change.
@@ -150,7 +150,10 @@ func (d *diffCmd) run() error {
 	seenAnyChanges := diff.DiffManifests(currentSpecs, newSpecs, d.suppressedKinds, d.outputContext, 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 Error{
+			error: errors.New("identified at least one change, exiting with non-zero exit code (detailed-exitcode parameter enabled)"),
+			Code:  2,
+		}
 	}
 
 	return nil

diff/diff.go

@@ -3,8 +3,8 @@ package diff
 import (
 	"fmt"
 	"io"
-	"strings"
 	"math"
+	"strings"
 
 	"github.com/aryann/difflib"
 	"github.com/mgutz/ansi"

main.go

@@ -1,15 +1,20 @@
 package main
 
 import (
-	"os"
 	"fmt"
+	"os"
 
 	"github.com/databus23/helm-diff/cmd"
 )
 
 func main() {
 	if err := cmd.New().Execute(); err != nil {
 		fmt.Println(err)
-		os.Exit(1)
+		switch e := err.(type) {
+		case cmd.Error:
+			os.Exit(e.Code)
+		default:
+			os.Exit(1)
+		}
 	}
 }