feat: make chart hook output configurable. (#18)

Also logs a warning when chart hooks are contained within the output.

Relates to #16

README.md

@@ -191,6 +191,7 @@ It exposes a `Helm` struct that provides a `Render()` function that returns the
 | `exclude[].kind` |  | Excludes resources by kind. |
 | `exclude[].namespace` |  | Excludes resources by namespace. |
 | `exclude[].name` |  | Excludes resources by name. |
+| `excludeHooks` | `--no-hooks` | If enabled excludes chart hooks from the output. |
 | `namespace` | `--namespace` | Set the namespace used by Helm templates. |
 | `namespacedOnly` | `--namespaced-only` | If enabled fail on known cluster-scoped resources and those of unknown kinds. |
 | `forceNamespace` | `--force-namespace` | Set namespace on all namespaced resources (and those of unknown kinds). |

cmd/khelm/fn.go

@@ -151,10 +151,9 @@ func mapOutputPaths(resources []*yaml.RNode, outputMappings []kptFnOutputMapping
 			continue
 		}
 
-		resID := meta.GetIdentifier()
 		outPath := defaultOutputPath
 		for i, m := range matchers {
-			if m.Match(&resID) {
+			if m.Match(&meta) {
 				outPath = outputMappings[i].OutputPath
 				break
 			}

cmd/khelm/template.go

@@ -68,6 +68,9 @@ func templateCommand(h *helm.Helm, writer io.Writer) *cobra.Command {
 	f.StringSliceVarP(&req.ValueFiles, "values", "f", nil, "Specify values in a YAML file or a URL (can specify multiple)")
 	f.StringSliceVar(&req.APIVersions, "api-versions", nil, "Kubernetes api versions used for Capabilities.APIVersions")
 	f.StringVar(&req.KubeVersion, "kube-version", req.KubeVersion, "Kubernetes version used as Capabilities.KubeVersion.Major/Minor")
+	f.BoolVar(&req.ExcludeHooks, "no-hooks", req.ExcludeHooks, "If enabled hooks are omitted from the output")
+	f.BoolVar(&req.ExcludeHooks, "exclude-hooks", req.ExcludeHooks, "If enabled hooks are omitted from the output")
+	f.Lookup("exclude-hooks").Hidden = true
 	f.StringVarP(&outOpts.FileOrDir, "output", "o", "-", "Write rendered output to given file or directory (as kustomization)")
 	f.BoolVar(&outOpts.Replace, "output-replace", false, "Delete and recreate the whole output directory or file")
 	return cmd

cmd/khelm/template_test.go

@@ -84,6 +84,16 @@ func TestTemplateCommand(t *testing.T) {
 			[]string{filepath.Join(exampleDir, "force-namespace"), "--force-namespace=forced-namespace"},
 			5, "namespace: forced-namespace",
 		},
+		{
+			"chart-hooks",
+			[]string{filepath.Join(exampleDir, "chart-hooks")},
+			10, "helm.sh/hook",
+		},
+		{
+			"chart-hooks-excluded",
+			[]string{filepath.Join(exampleDir, "chart-hooks"), "--no-hooks"},
+			1, "myvalue",
+		},
 	} {
 		t.Run(c.name, func(t *testing.T) {
 			var out bytes.Buffer

e2e/cli-tests.bats

@@ -1,6 +1,7 @@
 #!/usr/bin/env bats
 
 IMAGE=${IMAGE:-mgoltzsche/khelm:latest}
+EXAMPLE_DIR="$(pwd)/example"
 OUT_DIR="$(mktemp -d)"
 
 teardown() {
@@ -18,7 +19,7 @@ teardown() {
 }
 
 @test "CLI should output kustomization" {
-	docker run --rm -u $(id -u):$(id -g) -v "$OUT_DIR:/out" -v "$(pwd)/example/namespace:/chart" "$IMAGE" template /chart \
+	docker run --rm -u $(id -u):$(id -g) -v "$OUT_DIR:/out" -v "$EXAMPLE_DIR/namespace:/chart" "$IMAGE" template /chart \
 		--output /out/kdir/ \
 		--debug
 	ls -la "$OUT_DIR" "$OUT_DIR/kdir" >&2

example/chart-hooks-disabled/generator.yaml

@@ -0,0 +1,6 @@
+apiVersion: khelm.mgoltzsche.github.com/v1
+kind: ChartRenderer
+metadata:
+  name: chart-hooks-disabled
+chart: ../chart-hooks
+excludeHooks: true

example/chart-hooks-disabled/kustomization.yaml

@@ -0,0 +1,2 @@
+generators:
+- generator.yaml

example/chart-hooks/Chart.yaml

@@ -0,0 +1,4 @@
+apiVersion: v1
+description: example chart with helm hooks
+name: hooks
+version: 0.1.0

example/chart-hooks/README.md

@@ -0,0 +1,5 @@
+# Example with Helm Chart Hooks
+
+This is an example kustomization that renders a local Helm chart that contains [hooks](https://helm.sh/docs/topics/charts_hooks/).  
+
+Corresponding to the `helm template` behaviour khelm returns all hook resources unless hooks are disabled explicitly.

example/chart-hooks/generator.yaml

@@ -0,0 +1,8 @@
+apiVersion: khelm.mgoltzsche.github.com/v1
+kind: ChartRenderer
+metadata:
+  name: chart-hooks
+chart: .
+exclude:
+- kind: Job
+  name: chart-hooks-post-rollback

example/chart-hooks/kustomization.yaml

@@ -0,0 +1,2 @@
+generators:
+- generator.yaml

example/chart-hooks/templates/configmap.yaml

@@ -0,0 +1,7 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: "{{ .Release.Name }}-myconfig"
+  namespace: {{ .Release.Namespace }}
+data:
+  key: myvalue

example/chart-hooks/templates/post-delete-hook.yaml

@@ -0,0 +1,21 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-post-delete"
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app.kubernetes.io/managed-by: {{ .Release.Service | quote }}
+    app.kubernetes.io/instance: {{ .Release.Name | quote }}
+    app.kubernetes.io/version: {{ .Chart.AppVersion }}
+    helm.sh/chart: "{{ .Chart.Name }}-{{ .Chart.Version }}"
+  annotations:
+    "helm.sh/hook": post-delete
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/post-install-hook.yaml

@@ -0,0 +1,21 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-post-install"
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app.kubernetes.io/managed-by: {{ .Release.Service | quote }}
+    app.kubernetes.io/instance: {{ .Release.Name | quote }}
+    app.kubernetes.io/version: {{ .Chart.AppVersion }}
+    helm.sh/chart: "{{ .Chart.Name }}-{{ .Chart.Version }}"
+  annotations:
+    "helm.sh/hook": post-install,post-upgrade
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/post-rollback-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-post-rollback"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": post-rollback
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/post-upgrade-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-post-upgrade"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": post-upgrade
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/pre-delete-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-pre-delete"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": pre-delete
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/pre-install-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-pre-install"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": pre-install
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/pre-rollback-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-pre-rollback"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": pre-rollback
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/pre-upgrade-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-pre-upgrade"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": pre-upgrade
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

example/chart-hooks/templates/test-hook.yaml

@@ -0,0 +1,16 @@
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: "{{ .Release.Name }}-test"
+  namespace: {{ .Release.Namespace }}
+  annotations:
+    "helm.sh/hook": test
+    "helm.sh/hook-weight": "-5"
+    "helm.sh/hook-delete-policy": hook-succeeded
+spec:
+  template:
+    spec:
+      restartPolicy: Never
+      containers:
+      - name: task
+        image: "alpine:3.13"

internal/matcher/matcher.go

@@ -2,23 +2,19 @@ package matcher
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/mgoltzsche/khelm/pkg/config"
 	"github.com/pkg/errors"
+	"sigs.k8s.io/kustomize/kyaml/yaml"
 )
 
-// KubernetesResourceMeta represents a kubernetes resource's meta data
-type KubernetesResourceMeta interface {
-	GetAPIVersion() string
-	GetKind() string
-	GetNamespace() string
-	GetName() string
-}
+const annotationHelmHook = "helm.sh/hook"
 
 // ResourceMatchers is a group of matchers
 type ResourceMatchers interface {
-	Match(o KubernetesResourceMeta) bool
+	Match(o *yaml.ResourceMeta) bool
 	RequireAllMatched() error
 }
 
@@ -29,8 +25,8 @@ func Any() ResourceMatchers {
 
 type matchAny struct{}
 
-func (m *matchAny) RequireAllMatched() error          { return nil }
-func (m *matchAny) Match(KubernetesResourceMeta) bool { return true }
+func (m *matchAny) RequireAllMatched() error      { return nil }
+func (m *matchAny) Match(*yaml.ResourceMeta) bool { return true }
 
 type resourceMatchers []*resourceMatcher
 
@@ -53,17 +49,25 @@ func (m resourceMatchers) RequireAllMatched() error {
 	return nil
 }
 
-// MatchAny returns true if any matches matches the given object
-func (m resourceMatchers) Match(o KubernetesResourceMeta) bool {
+// Match returns true if any matches matches the given object
+func (m resourceMatchers) Match(o *yaml.ResourceMeta) bool {
 	for _, e := range m {
-		if e.ResourceSelector.Match(o) {
+		if matchSelector(&e.ResourceSelector, o) {
 			e.Matched = true
 			return true
 		}
 	}
 	return false
 }
 
+// matchSelector returns true if all non-empty fields of the selector match the ones in the provided object
+func matchSelector(id *config.ResourceSelector, o *yaml.ResourceMeta) bool {
+	return (id.APIVersion == "" || id.APIVersion == o.APIVersion) &&
+		(id.Kind == "" || id.Kind == o.Kind) &&
+		(id.Namespace == "" || id.Namespace == o.Namespace) &&
+		(id.Name == "" || id.Name == o.Name)
+}
+
 // FromResourceSelectors creates matchers from the provided selectors
 func FromResourceSelectors(selectors []config.ResourceSelector) ResourceMatchers {
 	matchers := make([]*resourceMatcher, len(selectors))
@@ -72,3 +76,47 @@ func FromResourceSelectors(selectors []config.ResourceSelector) ResourceMatchers
 	}
 	return resourceMatchers(matchers)
 }
+
+// ChartHookMatcher matches chart hook resources when the delegated matcher doesn't match
+type ChartHookMatcher struct {
+	ResourceMatchers
+	delegateOnly bool
+	hooks        map[string]struct{}
+}
+
+// NewChartHookMatcher creates
+func NewChartHookMatcher(delegate ResourceMatchers, delegateOnly bool) *ChartHookMatcher {
+	return &ChartHookMatcher{
+		ResourceMatchers: delegate,
+		delegateOnly:     delegateOnly,
+		hooks:            map[string]struct{}{},
+	}
+}
+
+// FoundHooks returns all hooks that weren't matched by the delegate matcher
+func (m *ChartHookMatcher) FoundHooks() []string {
+	hooks := make([]string, 0, len(m.hooks))
+	for hook := range m.hooks {
+		hooks = append(hooks, hook)
+	}
+	sort.Strings(hooks)
+	return hooks
+}
+
+// Match returns true if any matches matches the given object
+func (m *ChartHookMatcher) Match(o *yaml.ResourceMeta) bool {
+	if m.ResourceMatchers.Match(o) {
+		return true
+	}
+
+	isHook := false
+	if a := o.Annotations; a != nil {
+		for _, hook := range strings.Split(a[annotationHelmHook], ",") {
+			if hook = strings.TrimSpace(hook); hook != "" {
+				m.hooks[hook] = struct{}{}
+				isHook = true
+			}
+		}
+	}
+	return isHook && !m.delegateOnly
+}