Add support for uses_kubernetes_features metadata

uses_kubernetes_features is a new tile attribute that allows K8s consumer tiles
to restrict which K8s distribution tiles can be assigned to it by matching
those features against the distribution's features. This commit updates `kiln
carvel bake` to pass through the new attribute.

ai-assisted=yes
[TNZ-120804] Define available_kubernetes_features / uses_kubernetes_features tile metadata schema

Author: ystros

internal/carvel/baker.go

@@ -611,6 +611,7 @@ func (b *baker) generateBaseYaml() error {
 	meta.Rank = b.metadata.Rank
 	meta.Serial = b.metadata.Serial
 	meta.CompatibleKubernetesDistributions = b.metadata.CompatibleKubernetesDistributions
+	meta.UsesKubernetesFeatures = b.metadata.UsesKubernetesFeatures
 	meta.FormTypes = b.metadata.FormTypes
 	meta.PropertyBlueprints = b.metadata.PropertyBlueprints
 	meta.Variables = b.metadata.Variables

internal/carvel/baker_test.go

@@ -361,6 +361,11 @@ consumes:
 					Expect(outMeta.CompatibleKubernetesDistributions[0].Name).To(Equal("k0s"))
 					Expect(outMeta.CompatibleKubernetesDistributions[0].Version).To(Equal(">0.0.0"))
 					Expect(outMeta.RequiresKubernetes).To(BeTrue())
+					Expect(outMeta.UsesKubernetesFeatures).To(HaveLen(2))
+					Expect(outMeta.UsesKubernetesFeatures[0].Name).To(Equal("gpu-scheduling"))
+					Expect(outMeta.UsesKubernetesFeatures[0].Optional).To(BeFalse())
+					Expect(outMeta.UsesKubernetesFeatures[1].Name).To(Equal("node-local-storage"))
+					Expect(outMeta.UsesKubernetesFeatures[1].Optional).To(BeTrue())
 				})
 				It("creates empty instance_group and jobs directories", func() {
 					Expect(filepath.Join(outputPath, "instance_groups")).To(BeADirectory())
@@ -495,6 +500,51 @@ consumes:
 					Expect(err.Error()).To(ContainSubstring("tile metadata_version too old"))
 				})
 			})
+			When("the tile declares no kubernetes features", func() {
+				// Ops Manager rejects uses_kubernetes_features on a tile that is not a
+				// kubernetes consumer, so an absent block must stay absent rather than
+				// baking out as an empty list.
+				BeforeEach(func() {
+					m := models.Metadata{
+						Name:                     "k8s-tile-test",
+						Label:                    "test tile",
+						IconImage:                "$( icon )",
+						MetadataVersion:          "3.2.0",
+						MinimumVersionForUpgrade: "0.0.0",
+						ProductVersion:           "$( version )",
+						Rank:                     1,
+						Serial:                   false,
+						PropertyBlueprints: []string{
+							`$( property "database_name" )`,
+							`$( property "admin_password" )`,
+						},
+						FormTypes:                         []string{`$( form "db_props" )`},
+						Variables:                         []proofing.Variable{},
+						PackageInstalls:                   []string{`$( package "test-install" )`},
+						CompatibleKubernetesDistributions: []models.ProductVersion{{Name: "k0s", Version: ">0.0.0"}},
+					}
+					yamlData, err := yaml.Marshal(&m)
+					Expect(err).NotTo(HaveOccurred())
+					Expect(string(yamlData)).NotTo(ContainSubstring("uses_kubernetes_features"))
+					err = os.WriteFile(path.Join(inputPath, "base.yml"), yamlData, 0644)
+					Expect(err).NotTo(HaveOccurred())
+				})
+
+				It("omits uses_kubernetes_features from the baked metadata", func() {
+					Expect(err).NotTo(HaveOccurred())
+
+					yamlData, readErr := os.ReadFile(path.Join(outputPath, "base.yml"))
+					Expect(readErr).NotTo(HaveOccurred())
+					Expect(string(yamlData)).NotTo(ContainSubstring("uses_kubernetes_features"))
+
+					outMeta := models.MetadataOut{}
+					Expect(yaml.Unmarshal(yamlData, &outMeta)).To(Succeed())
+					Expect(outMeta.UsesKubernetesFeatures).To(BeEmpty())
+					// the rest of the kubernetes metadata is unaffected
+					Expect(outMeta.RequiresKubernetes).To(BeTrue())
+					Expect(outMeta.CompatibleKubernetesDistributions).To(HaveLen(1))
+				})
+			})
 		})
 	})
 

internal/carvel/models/metadata.go

@@ -16,4 +16,5 @@ type Metadata struct {
 	Variables                         []proofing.Variable `yaml:"variables"`
 	PackageInstalls                   []string            `yaml:"package_installs"`
 	CompatibleKubernetesDistributions []ProductVersion    `yaml:"compatible_kubernetes_distributions,omitempty"`
+	UsesKubernetesFeatures            []KubernetesFeature `yaml:"uses_kubernetes_features,omitempty"`
 }

internal/carvel/models/metadata_out.go

@@ -20,6 +20,7 @@ type MetadataOut struct {
 	RuntimeConfigs                    []string            `yaml:"runtime_configs"`
 	RequiresKubernetes                bool                `yaml:"requires_kubernetes"`
 	CompatibleKubernetesDistributions []ProductVersion    `yaml:"compatible_kubernetes_distributions"`
+	UsesKubernetesFeatures            []KubernetesFeature `yaml:"uses_kubernetes_features,omitempty"`
 }
 
 type StemcellCriteria struct {
@@ -31,3 +32,11 @@ type ProductVersion struct {
 	Name    string `yaml:"name"`
 	Version string `yaml:"version"`
 }
+
+// KubernetesFeature is a single entry in a consumer tile's uses_kubernetes_features.
+// Optional is omitted when false so that baked metadata matches the source tile: Ops
+// Manager already defaults an absent optional to false.
+type KubernetesFeature struct {
+	Name     string `yaml:"name"`
+	Optional bool   `yaml:"optional,omitempty"`
+}

internal/carvel/testdata/sample-tile/base.yml

@@ -23,3 +23,7 @@ package_installs:
 compatible_kubernetes_distributions:
 - name: k0s
   version: '>0.0.0'
+uses_kubernetes_features:
+- name: gpu-scheduling
+- name: node-local-storage
+  optional: true