Place rendering invalid YAML under --debug flag

Signed-off-by: Reinhard Naegele <unguiculus@gmail.com>

cmd/helm/template.go

@@ -65,8 +65,15 @@ func newTemplateCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			client.IncludeCRDs = includeCrds
 			rel, err := runInstall(args, client, valueOpts, out)
 
-			// We ignore a potential error here because we always want to print the YAML,
-			// even if it is not valid. The error is still returned afterwards.
+			if err != nil && !settings.Debug {
+				if rel != nil {
+					return fmt.Errorf("%w\n\nUse --debug flag to render out invalid YAML", err)
+				}
+				return err
+			}
+
+			// We ignore a potential error here because, when the --debug flag was specified,
+			// we always want to print the YAML, even if it is not valid. The error is still returned afterwards.
 			if rel != nil {
 				var manifests bytes.Buffer
 				fmt.Fprintln(&manifests, strings.TrimSpace(rel.Manifest))

cmd/helm/template_test.go

@@ -108,6 +108,12 @@ func TestTemplateCmd(t *testing.T) {
 			wantError: true,
 			golden:    "output/template-with-invalid-yaml.txt",
 		},
+		{
+			name:      "chart with template with invalid yaml (--debug)",
+			cmd:       fmt.Sprintf("template '%s' --debug", "testdata/testcharts/chart-with-template-with-invalid-yaml"),
+			wantError: true,
+			golden:    "output/template-with-invalid-yaml-debug.txt",
+		},
 	}
 	runTestCmd(t, tests)
 }

cmd/helm/testdata/output/template-with-invalid-yaml-debug.txt

@@ -0,0 +1,13 @@
+---
+# Source: chart-with-template-with-invalid-yaml/templates/alpine-pod.yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: "RELEASE-NAME-my-alpine"
+spec:
+  containers:
+  - name: waiter
+    image: "alpine:3.9"
+    command: ["/bin/sleep","9000"]
+invalid
+Error: YAML parse error on chart-with-template-with-invalid-yaml/templates/alpine-pod.yaml: error converting YAML to JSON: yaml: line 11: could not find expected ':'

cmd/helm/testdata/output/template-with-invalid-yaml.txt

@@ -1,13 +1,3 @@
----
-# Source: chart-with-template-with-invalid-yaml/templates/alpine-pod.yaml
-apiVersion: v1
-kind: Pod
-metadata:
-  name: "RELEASE-NAME-my-alpine"
-spec:
-  containers:
-  - name: waiter
-    image: "alpine:3.9"
-    command: ["/bin/sleep","9000"]
-invalid
 Error: YAML parse error on chart-with-template-with-invalid-yaml/templates/alpine-pod.yaml: error converting YAML to JSON: yaml: line 11: could not find expected ':'
+
+Use --debug flag to render out invalid YAML