provisioner: improve empty manifest detection

Reuse existing YAML marshaler to detect empty manifests.

Signed-off-by: Alexander Yastrebov <[email protected]>

provisioner/clusterpy.go

@@ -9,7 +9,6 @@ import (
 	"net/url"
 	"strings"
 	"time"
-	"unicode"
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/service/cloudformation"
@@ -1042,7 +1041,7 @@ func remarshalYAML(contents string) (string, error) {
 		}
 	}
 
-	return string(result.Bytes()), nil
+	return result.String(), nil
 }
 
 func renderManifests(config channel.Config, cluster *api.Cluster, values map[string]interface{}, adapter *awsAdapter) ([]manifestPackage, error) {
@@ -1068,19 +1067,18 @@ func renderManifests(config channel.Config, cluster *api.Cluster, values map[str
 				return nil, fmt.Errorf("error rendering template %s: %v", manifest.Path, err)
 			}
 
-			// If there's no content we skip the file.
-			if stripWhitespace(rendered) == "" {
-				log.Debugf("Skipping empty file: %s", manifest.Path)
-				continue
-			}
-
 			// We remarshal the manifest here to get rid of references
 			remarshaled, err := remarshalYAML(rendered)
 			if err != nil {
 				return nil, fmt.Errorf("error remarshaling manifest %s: %v", manifest.Path, err)
 			}
 
-			renderedManifests = append(renderedManifests, remarshaled)
+			// If there's no content we skip the file.
+			if remarshaled == "" {
+				log.Debugf("Skipping empty file: %s\n%s\n", manifest.Path, rendered)
+			} else {
+				renderedManifests = append(renderedManifests, remarshaled)
+			}
 		}
 
 		if len(renderedManifests) > 0 {
@@ -1127,15 +1125,6 @@ func (p *clusterpyProvisioner) apply(ctx context.Context, logger *log.Entry, clu
 	return nil
 }
 
-func stripWhitespace(content string) string {
-	return strings.Map(func(r rune) rune {
-		if unicode.IsSpace(r) {
-			return -1
-		}
-		return r
-	}, content)
-}
-
 func int32Ptr(i int32) *int32 { return &i }
 
 func int32Value(v *int32) int32 {

provisioner/clusterpy_test.go

@@ -403,6 +403,72 @@ first: 1
 second: 2
 `,
 		},
+		{
+			name:     "empty manifest",
+			source:   "",
+			expected: "",
+		},
+		{
+			name:     "empty manifest with newline",
+			source:   "\n",
+			expected: "",
+		},
+		{
+			name:     "empty manifest with newlines",
+			source:   "\n\n",
+			expected: "",
+		},
+		{
+			name: "empty manifest with comments",
+			source: `
+# this manifest consists only
+
+  # of comments and
+
+    # whitespace lines
+`,
+			expected: "",
+		},
+		{
+			name:     "empty manifest with multiple documents",
+			source:   "---",
+			expected: "",
+		},
+		{
+			name:     "empty manifest with multiple documents",
+			source:   "\n---",
+			expected: "",
+		},
+		{
+			name:     "empty manifest with multiple documents",
+			source:   "---\n",
+			expected: "",
+		},
+		{
+			name:     "empty manifest with multiple documents",
+			source:   "\n---\n",
+			expected: "",
+		},
+		{
+			name: "empty manifest with multiple documents and comments",
+			source: `
+
+# this multidoc manifest
+# consists only
+
+
+---
+  # of comments and
+
+---
+    # whitespace lines
+---
+---
+
+---
+`,
+			expected: "",
+		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			remarshaled, err := remarshalYAML(tc.source)