Adding annotation to index.yaml file

Chart.yaml files have an annotation field that allow a chart to
have custom information similar to the way Kubernetes annotations
work.

In an index.yaml file each chart version can have annotations in
a similar manner to the Chart.yaml file. It is derived from the
same underlying struct.

These enable extension points where people can add their own info.

One thing missing is the ability to extend the top level of an
index file. This change adds annotations to the top level of an
index.yaml file. This would provide top level support for vendors
to extent index.yaml files.

Closes helm#8767

Signed-off-by: Matt Farina <matt@mattfarina.com>

pkg/repo/index.go

@@ -83,6 +83,10 @@ type IndexFile struct {
 	Generated  time.Time                `json:"generated"`
 	Entries    map[string]ChartVersions `json:"entries"`
 	PublicKeys []string                 `json:"publicKeys,omitempty"`
+
+	// Annotations are additional mappings uninterpreted by Helm. They are made available for
+	// other applications to add information to the index file.
+	Annotations map[string]string `json:"annotations,omitempty"`
 }
 
 // NewIndexFile initializes an index.

pkg/repo/index_test.go

@@ -36,6 +36,7 @@ import (
 
 const (
 	testfile            = "testdata/local-index.yaml"
+	annotationstestfile = "testdata/local-index-annotations.yaml"
 	chartmuseumtestfile = "testdata/chartmuseum-index.yaml"
 	unorderedTestfile   = "testdata/local-index-unordered.yaml"
 	testRepo            = "test-repo"
@@ -153,6 +154,21 @@ func TestLoadIndexFile(t *testing.T) {
 	verifyLocalIndex(t, i)
 }
 
+func TestLoadIndexFileAnnotations(t *testing.T) {
+	i, err := LoadIndexFile(annotationstestfile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	verifyLocalIndex(t, i)
+
+	if len(i.Annotations) != 1 {
+		t.Fatalf("Expected 1 annotation but got %d", len(i.Annotations))
+	}
+	if i.Annotations["helm.sh/test"] != "foo bar" {
+		t.Error("Did not get expected value for helm.sh/test annotation")
+	}
+}
+
 func TestLoadUnorderedIndex(t *testing.T) {
 	b, err := ioutil.ReadFile(unorderedTestfile)
 	if err != nil {

pkg/repo/testdata/local-index-annotations.yaml

@@ -0,0 +1,50 @@
+apiVersion: v1
+entries:
+  nginx:
+    - urls:
+        - https://kubernetes-charts.storage.googleapis.com/nginx-0.2.0.tgz
+      name: nginx
+      description: string
+      version: 0.2.0
+      home: https://github.com/something/else
+      digest: "sha256:1234567890abcdef"
+      keywords:
+        - popular
+        - web server
+        - proxy
+    - urls:
+        - https://kubernetes-charts.storage.googleapis.com/nginx-0.1.0.tgz
+      name: nginx
+      description: string
+      version: 0.1.0
+      home: https://github.com/something
+      digest: "sha256:1234567890abcdef"
+      keywords:
+        - popular
+        - web server
+        - proxy
+  alpine:
+    - urls:
+        - https://kubernetes-charts.storage.googleapis.com/alpine-1.0.0.tgz
+        - http://storage2.googleapis.com/kubernetes-charts/alpine-1.0.0.tgz
+      name: alpine
+      description: string
+      version: 1.0.0
+      home: https://github.com/something
+      keywords:
+        - linux
+        - alpine
+        - small
+        - sumtin
+      digest: "sha256:1234567890abcdef"
+  chartWithNoURL:
+    - name: chartWithNoURL
+      description: string
+      version: 1.0.0
+      home: https://github.com/something
+      keywords:
+        - small
+        - sumtin
+      digest: "sha256:1234567890abcdef"
+annotations:
+  helm.sh/test: foo bar