feat: support verbatim patch values (#25)

Author: porridge

.github/workflows/go.yml

@@ -11,5 +11,7 @@ jobs:
     - uses: actions/checkout@v4
     - name: Set up Go
       uses: actions/setup-go@v5
+      with:
+        go-version-file: go.mod
     - name: CI
       run: make ci

README.md

@@ -95,6 +95,11 @@ type K8sObjectOverlayPatch struct {
 	// All values are strings but are converted into appropriate type based on schema.
 	//+operator-sdk:csv:customresourcedefinitions:type=spec,displayName="Value",order=2
 	Value string `json:"value,omitempty"`
+	// Verbatim value to add, delete or replace.
+	// Same as Value, however the content is not interpreted as YAML, but treated as literal string instead.
+	// At least one of Value and Verbatim must be empty.
+	//+operator-sdk:csv:customresourcedefinitions:type=spec,displayName="Verbatim",order=3
+	Verbatim string `json:"verbatim,omitempty"`
 }
 
 ```
@@ -132,8 +137,9 @@ func mapOverlayPatches(patches []*v1alpha1.K8sObjectOverlayPatch) []*types.K8sOb
 	out := make([]*types.K8sObjectOverlayPatch, len(patches))
 	for i, p := range patches {
 		out[i] = &types.K8sObjectOverlayPatch{
-			Path:  p.Path,
-			Value: p.Value,
+			Path:     p.Path,
+			Value:    p.Value,
+			Verbatim: p.Verbatim,
 		}
 	}
 	return out
@@ -164,5 +170,7 @@ spec:
     - path: data.foo
       value: bar
     - path: data.baz
-      value: qux
+      verbatim: |
+        qux
+        separate lines
 ```

pkg/patch/patch.go

@@ -133,6 +133,9 @@ func YAMLManifestPatch(baseYAML string, defaultNamespace string, overlays []*typ
 	if err != nil {
 		return "", err
 	}
+	for i, overlay := range overlays {
+		errs = util.AppendErr(errs, validateOverlay(i, overlay))
+	}
 
 	matches := make(map[*types.K8sObjectOverlay]object.K8sObjects)
 	// Try to apply the defined overlays.
@@ -175,6 +178,16 @@ func YAMLManifestPatch(baseYAML string, defaultNamespace string, overlays []*typ
 	return ret.String(), errs.ToError()
 }
 
+func validateOverlay(overlayIndex int, overlay *types.K8sObjectOverlay) error {
+	var errs util.Errors
+	for patchIndex, patch := range overlay.Patches {
+		if patch.Value != "" && patch.Verbatim != "" {
+			errs = util.AppendErr(errs, fmt.Errorf("value and verbatim cannot be used together in overlay %d patch %d", overlayIndex, patchIndex))
+		}
+	}
+	return errs.ToError()
+}
+
 // applyPatches applies the given patches against the given object. It returns the resulting patched YAML if successful,
 // or a list of errors otherwise.
 func applyPatches(base *object.K8sObject, patches []*types.K8sObjectOverlayPatch) (outYAML string, errs util.Errors) {
@@ -189,25 +202,28 @@ func applyPatches(base *object.K8sObject, patches []*types.K8sObjectOverlayPatch
 		return "", util.NewErrs(err)
 	}
 	for _, p := range patches {
-
-		var v = &structpb.Value{}
-		if err := util.UnmarshalWithJSONPB(p.Value, v, false); err != nil {
-			errs = util.AppendErr(errs, err)
-			continue
+		var value interface{}
+		if p.Verbatim != "" && p.Value == "" {
+			value = p.Verbatim
+		} else {
+			var v = &structpb.Value{}
+			if err := util.UnmarshalWithJSONPB(p.Value, v, false); err != nil {
+				errs = util.AppendErr(errs, err)
+				continue
+			}
+			value = v.AsInterface()
 		}
-
 		if strings.TrimSpace(p.Path) == "" {
-			scope.V(2).Info("skipping empty path", "value", p.Value)
+			scope.V(2).Info("skipping empty path", "value", value)
 			continue
 		}
-		scope.Info("applying", "path", p.Path, "value", p.Value)
+		scope.Info("applying", "path", p.Path, "value", value)
 		inc, _, err := tpath.GetPathContext(bo, util.PathFromString(p.Path), true)
 		if err != nil {
 			errs = util.AppendErr(errs, err)
 			continue
 		}
-
-		err = tpath.WritePathContext(inc, v.AsInterface(), false)
+		err = tpath.WritePathContext(inc, value, false)
 		if err != nil {
 			errs = util.AppendErr(errs, err)
 		}

pkg/patch/patch_test.go

@@ -17,6 +17,8 @@ package patch
 import (
 	"fmt"
 	"github.com/stackrox/k8s-overlay-patch/pkg/types"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"gopkg.in/yaml.v3"
 	"testing"
 
@@ -27,6 +29,20 @@ type KubernetesResourcesSpec struct {
 	Overlays []*types.K8sObjectOverlay `json:"overlays"`
 }
 
+func TestYAMLManifestPatchValidation(t *testing.T) {
+	_, err := YAMLManifestPatch("", "", []*types.K8sObjectOverlay{
+		{
+			Patches: []*types.K8sObjectOverlayPatch{
+				{
+					Value:    "a",
+					Verbatim: "b",
+				},
+			},
+		},
+	})
+	assert.ErrorContains(t, err, "value and verbatim cannot be used together in overlay 0 patch 0")
+}
+
 func TestPatchYAMLManifestSuccess(t *testing.T) {
 	base := `
 apiVersion: apps/v1
@@ -493,6 +509,66 @@ spec:
 	}
 }
 
+func TestPatchYAMLConfigMap(t *testing.T) {
+	base := `
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: a-cm
+  namespace: stackrox
+data:
+  postgresql.conf: |
+    hba_file = '/etc/stackrox.d/config/pg_hba.conf'
+    foo = "bar"
+    log_timezone = 'Etc/UTC' # comment
+    more = true
+  hba.conf: |-
+    # PostgreSQL Client Authentication Configuration File
+    local   all             all                                     scram-sha-256
+`
+
+	overlays := `overlays:
+- apiVersion: v1
+  kind: ConfigMap
+  name: a-cm
+  patches:
+  - path: data.postgresql\.conf
+    verbatim: |
+      hba_file = '/etc/stackrox.d/config/pg_hba.conf'
+      foo = "bar"
+
+      log_timezone = 'Etc/UTC' # comment
+      more = false
+`
+	want := `
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: a-cm
+  namespace: stackrox
+data:
+  postgresql.conf: |
+    hba_file = '/etc/stackrox.d/config/pg_hba.conf'
+    foo = "bar"
+
+    log_timezone = 'Etc/UTC' # comment
+    more = false
+  hba.conf: |-
+    # PostgreSQL Client Authentication Configuration File
+    local   all             all                                     scram-sha-256
+`
+	rc := &KubernetesResourcesSpec{}
+	if err := yaml.Unmarshal([]byte(overlays), rc); err != nil {
+		t.Fatalf("yaml.Unmarshal(): got error %s for string:\n%s\n", err, overlays)
+	}
+	t.Logf("%+v", rc.Overlays[0].Patches[0].Value)
+	got, err := YAMLManifestPatch(base, "stackrox", rc.Overlays)
+	require.NoError(t, err, "YAMLManifestPatch failed")
+	if !util.IsYAMLEqual(got, want) {
+		t.Errorf("YAMLManifestPatch(): got:\n%s\n\nwant:\n%s\nDiff:\n%s\n", got, want, util.YAMLDiff(got, want))
+	}
+}
+
 func makeOverlayHeader(path, value string) string {
 	const (
 		patchCommon = `overlays:

pkg/types/overlay.go

@@ -39,6 +39,10 @@ type K8sObjectOverlayPatch struct {
 	// For replace, path should reference an existing node.
 	// All values are strings but are converted into appropriate type based on schema.
 	Value string `json:"value,omitempty"`
+	// Verbatim value to add, delete or replace.
+	// Same as Value, however the content is not interpreted as YAML, but treated as literal string instead.
+	// At least one of Value and Verbatim must be empty.
+	Verbatim string `json:"verbatim,omitempty"`
 }
 
 type OverlayObject struct {